REPORT OF THE WESTERN AUSTRALIAN …/media/Files/Hospitals...REPORT OF THE WESTERN AUSTRALIAN CEREBRAL PALSY REGISTER TO BIRTH YEAR 1999 Linda Watson Eve Blair, PhD Fiona Stanley AC

REPORT OF THE WESTERN AUSTRALIANCEREBRAL PALSY REGISTER

TO BIRTH YEAR 1999

TELE

THON INSTITUTE FO

R

Child HealthResearchJuly 2006

ACkNOWLEdGEmENTSWe are very grateful to the NHMRC who currently fund this work and the other funding bodies (see Funding p2) who have supported the Register since its inception.

Our special thanks go to the many health professionals who provide all information held on the Register and to the service agencies that have assisted and encouraged this research undertaking over the years. Our work would not be possible without their help. We are particularly grateful to the therapists in the country centres whose responses to our annual requests are essential to the completeness and accuracy of the Register.

The Register would be of little use without information on births and deaths throughout the State which make up our comparison population data. This is provided by the Registrar General of Western Australia from birth and death certificates, also by Vivian Gee, Co-ordinator of the Midwives Notification of Births System at the Health Department of Western Australia. We are grateful to all midwives who contribute to this high quality data collection which greatly enhances our ability to study maternal, obstetric and perinatal factors in relation to cerebral palsy.

We also gratefully acknowledge the members of our Advisory Committee for their continued support over the years, our Honorary Consultants who have guided our decisions and research directions, the late Dr Louisa Alessandri for her valuable assistance, and the many other people, too numerous to mention individually, who have been responsible for improving the data held on the Register and our ability to use it.

Last, but certainly not least, a very big thanks to Heather Monteiro for the design and development of this Report.

REPORT OFTHE WESTERN AUSTRALIANCEREBRAL PALSY REGISTER

TO BIRTH YEAR 1999

Linda WatsonEve Blair, PhD

Fiona Stanley ACFAA, FASSA, MBBS, MSc, MD, FFPHM, FAFPHM,

FRACP, FRANZCOG, Hon DSc, Hon DUniv,Hon FRACGP, Hon MD, Hon FRCPCH

Telethon Institute for Child Health ResearchPO Box 855 West Perth, Western Australia 6872

AUSTRALIA

................................................................ REPORT OF THE WESTERN AUSTRALIAN CEREBRAL PALSY REGISTER ................................................................................2

THE WESTERN AUSTRALIAN CEREBRAL PALSY REGISTER

Principal Investigators: Professor Fiona Stanley Associate Professor Eve Blair

Associate Investigators: Dr Beverly Petterson Dr Nadia Badawi Dr Jennifer Kurinczuk Dr Karin Nelson

Research Offi cer: Ms Jan de Groot

Research Assistant: Ms Linda Watson

Computer programmers: Mr Peter Cosgrove Ms Margaret Wood

Honorary Consultant: Mrs Brenda Lake

Genetic Consultant: Dr Jennie Slee

Advisory Committee: Dr Peter Chauvel Dr Noel French (Chairperson) Dr Rex Henderson Dr Athel Hockey Dr Lakshmi Nagarajan Mrs Kerry Naso (Consumer representative) Dr Trevor Parry Dr Beverly Petterson Dr Jon Silberstein Dr Peter Silberstein Mrs Margaret Tait (Consumer representative) Dr Jane Valentine Dr Ian Walpole Dr Peter Walsh

................................................................ REPORT OF THE WESTERN AUSTRALIAN CEREBRAL PALSY REGISTER ......................................................................... 3

CONTENTS

Acknowledgements

Introduction ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... 5

Funding.. ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... . 5

Aims of the WA Cerebral Palsy Register . ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... . 6

The Australian Cerebral Palsy Register .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... . 6

Methods . ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... 7

Defi nition ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... . 7

Data collection .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... . 7

Record linkage .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... . 8

Denominators ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... . 8

Classifi cation system ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... . 9

Confi dentiality of data .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... 10

Ethical considerations... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... 10

Current projects .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... 11

International developments ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... 11

Results ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... .. 12

Overall birth prevalence... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... 12

Section I: Pre- and neonatally Acquired Cerebral Palsy ... ... ... ... ... ... ... ... ... ... ... ... ... .. 15

Gender of infant ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... 16

Birth weight and gestational age ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... 17

Plurality .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ...22

Area of residence . ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ...26

Indigenous status of mother ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ...29

Age of mother ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ...30

Previous births... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ...33

Severity of cerebral palsy . ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ...34

Type of cerebral palsy... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... 37

Associated disabilities:. ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... 47

(1) Intellectual disability . ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... 47

(2) Epilepsy, blindness, deafness and lack of speech ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... 51

Age at recognition of cerebral palsy... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ...52

Section II: Postneonatally Acquired Cerebral Palsy .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... . 55

Trends in postneonatally acquired cerebral palsy ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ...56

Gender... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... 57

Area of residence . ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ...58

Indigenous status of mother ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ...59

Age of mother ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ...60

Severity of cerebral palsy . ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... 61

Type of cerebral palsy... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ...63

Associated disabilities.. ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ...65

(1) Intellectual disability . ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ...65

(2) Epilepsy, blindness, deafness and lack of speech ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ...66

Postneonatal causes of cerebral palsy .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... 67

Postneonatal causes by indigenous status ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ...68

Postneonatal year of acquisition of cerebral palsy ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ...69

References.. ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ..70

APPENDICES ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ..73

APPENDIX A: Notifi cation card. ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... 75

APPENDIX B: Data collection form... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... 77

APPENDIX C: Description of cerebral palsy ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... 81

APPENDIX D: Gross Motor Function Classifi cation System ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ...85

APPENDIX E: Manual Ability Classifi cation System (MACS) ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ...89

APPENDIX F: Cerebral palsy publications (to July 2006) ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... 91


INTRODUCTION

The Western Australian Cerebral Palsy Register is a population-based data collection that has now been in existence for 26 years. Collection of data for the period 1956-1975 commenced in 1977 for the original epidemiological study of cerebral palsy in Western Australia1-3, and in 1979 additional funding made it possible to continue the data set as an ongoing Register. At that time some changes were made to the data collection and coding which account for some inconsistencies between the data sets before and after 1975 (1975 is included in both).

The Register uses multiple sources to ascertain all recognised cases of cerebral palsy born and/or living in Western Australia from 1956 onwards. This report includes only those cases who were born in Western Australia. Information held on the Register is updated when a child reaches the age of 5 years, by which time ascertainment of a birth-year cohort can be considered complete and accurate for inclusion in analyses. There is, therefore, a lag of fi ve years in reporting data, and all information regarding impairments contained in this report relates to fi ndings at the age of 5 years.

This report presents Register data in two Sections. Section I: Pre- and Perinatally Acquired Cerebral Palsy covers the years to 1999 in 5- or 10-year groups, from 1960 where Register and denominator data are available for earlier years; otherwise from 1975 or, where data by gestational age or Indigenous status are presented, from 1980. The Register collects cases due to postneonatal causes which occur up to the age of 5 years, and this group is presented separately in Section II: Postneonatally Acquired Cerebral Palsy.

Mortality data have been reported in a separate publication on the life expectancy of people with cerebral palsy in Western Australia4.

FUNDING

The initial data collection was funded in 1977 by NHMRC as part of Professor Fiona Stanley’s research fellowship, with additional funds from the King Edward Memorial Hospital Research Foundation and The Australian Neurological Foundation. In 1979 the TVW Telethon Foundation (later called Child Health Research Foundation of Western Australia) funded the Register as an ongoing project and continued this support to mid-1993; the Charles and Sylvia Viertel Research Foundation provided funding during the latter half of 1993. From 1994-96 the Register was funded jointly by Healthways and NHMRC and since 1997, solely by NHMRC as part of the Program Grant for Epidemiological Studies in Maternal and Child Health at the Telethon Institute for Child Health Research. We are very grateful for this support.


AIMS OF THE WA CEREBRAL PALSY REGISTER

The Western Australian Cerebral Palsy Register was set up with the following aims:

• to monitor trends in the cerebral palsies and identify areas of concern for future investigation,

• to conduct population-based epidemiological studies of the various cerebral palsy subgroups, particularly to elucidate causes,

• to evaluate changes in antenatal, obstetric and neonatal care in relation to cerebral palsy as an index of neurological outcome,

• to identify cerebral palsy as an outcome in other study populations,

• to aid in the planning of services for individuals with cerebral palsy, and it now aims also

• to contribute Western Australian data to the Australian Cerebral Palsy Register.

THE AUSTRALIAN CEREBRAL PALSY REGISTER

The Australian Cerebral Palsy Register (ACPR) commenced in 2002 as a collaborative project between all Australian States and Territories. While only three States - Western Australia, Victoria and South Australia - had established CP Registers at that time, there are now registers operating in every State and Territory.

The clearing house is located at the CP Institute in Sydney. A web-based IT system developed for the NSW Cerebral Palsy Register by corporate donors is available to all States and Territories as a means of data collection, management and transfer. Consistency in the classifi cation of cerebral palsy for the ACPR is being addressed by the development of an innovative system of recording clinical features of cerebral palsy using a specially designed form including a training DVD to assist in its introduction and trialling throughout Australia.

The ACPR was launched in Sydney by Professor Fiona Stanley during Cerebral Palsy Week in July 2007.


METHODS

DEFINITION

Cerebral palsy is defi ned by fi ve key elements: (1) it is a group of disorders, (2) it is permanent but not unchanging, (3) it involves a disorder of movement and/or posture and of motor function, (4) it is due to a non-progressive interference/lesion/abnormality, and (5) this interference/lesion/abnormality is in the developing immature brain5. Despite recent attempts to produce a defi nition suitable to all disciplines6,7, this defi nition remains the most appropriate for register purposes 8.

Cerebral palsy is a description rather than a diagnosis since no information about pathology, aetiology or prognosis can be inferred from it9. What is to be included in this broad defi nition must therefore be specifi ed. Criteria for the inclusion and exclusion of cases on the Western Australian Register, particularly with regard to syndromes that include a motor impairment, are presented in a paper, What constitutes cerebral palsy?10.

Limits on age of acquisition of cerebral palsy, age of survival, and inclusion of cases with postneonatal causes vary from register to register and must be made clear in order to assess comparability of fi ndings. These criteria, as they relate to the Western Australian Cerebral Palsy Register, are set out below.

DATA COLLECTION

The Register includes all individuals with cerebral palsy in Western Australia born from 1956 onwards. We include both children who were born here and those who migrate into WA to enable the number of children requiring services to be estimated; the group not born in WA are excluded from birth prevalence analyses.

Information is also collected on children with cerebral palsy due to clearly documented postneonatal causes occurring before the age of 5 years. This group is included in prevalence estimates but excluded from studies to investigate other causes of cerebral palsy. Since cases of cerebral palsy due to causes that apparently arise in the neonatal period are likely to be related to the uterine environment, they are classifi ed with the pre- and perinatally acquired group.

New cases are ascertained annually from multiple sources (see diagram below), including interstate centres to identify children with cerebral palsy who were born in WA but moved elsewhere before their cerebral palsy was recognised. Data on all cases are updated the year they turn 5, by which time most cases will have come to the attention of the Register, most impairments due to progressive syndromes will have been identifi ed, and impairments that are going to resolve will have done so. In the earlier years of the Register, children with cerebral palsy tended to be referred to one of the metropolitan centres for assessment. More recently there has been a trend to regionalisation of services and the number of data sources has increased considerably with these shifts in service provision.


Notifi cation cards (Appendix A) are used to request information on new cases where there is no direct access to medical records, such as regional and interstate centres.

Basic demographic, perinatal and diagnostic data are collected on a precoded form shown in Appendix B. The coding manual is available on request.

DATA SOURCES

Regional Child Healthand Development Centres

WA Cerebral

Palsy Register

Health Department Hospital morbidity data

WA Cerebral Palsy Association

Rural Paediatric Service

State Child Development Centre

Metropolitan and regionalhospital physiotherapy depts

Preterm birthfollow-up studies

Disability Services Commission

Interstate paediatricians andCP assessment centres

Private neurologists and paediatricians

Double-headed arrows indicate an arrangement of reciprocal notifi cation between the Cerebral Palsy Register and (1) the Rural Paediatric Service and (2) preterm birth follow up studies being carried out by neonatologists in Perth.

RECORD LINKAGE

Cerebral Palsy Register data are computerised using Ingres software as part of the Maternal and Child Health Research Data Base11 located at the Telethon Institute for Child Health Research. This enables linkage from 1980 onwards with records of all births in Western Australia, thus providing comparison data for the population and a sampling frame for selection of controls. With the appropriate ethics committee approvals, all data sets held on the Maternal and Child Health Research Data Base including data from 1980 onwards can be linked; these include live and stillbirths, deaths, hospital admissions, and the Western Australian Birth Defects Register. Cerebral Palsy Register data are stored electronically in coded form, and names are kept in a separate fi le.

DENOMINATORS

Denominator data for the years 1956 to 1979 were obtained from Australian Bureau of Statistics annual publications, Demography 196812 to 197913, and for 1980 onwards from the Births File on the Maternal and Child Health Research Data Base. It should be noted that population statistics prior to 1967 exclude full-blood Aboriginals.

A birth is defi ned as >=20 weeks gestation or >=400 grams birth weight, and a neonatal survivor as an infant who survives beyond the fi rst 28 days of life.


CLASSIFICATION SYSTEM

Since the early 1980s the problem of interobserver variation in the classifi cation of cerebral palsy has been addressed by holding regular meetings with doctors and therapists who assess and treat children with cerebral palsy in Western Australia.

This group of clinicians designed the cerebral palsy classifi cation form, Description of Motor and Other Disabilities (Appendix C), used in Western Australia until recently. This was based on the Standard Recording of Central Motor Defi cit14 form developed in the UK in consultation with the international community in the latter half of the 1980s to improve interobserver agreement in classifying cerebral palsy.

The WA Register codes cerebral palsy by type and distribution of spasticity:

1 = Right spastic hemiplegia (includes monoplegias)

2 = Left spastic hemiplegia (includes monoplegias)

3 = Spastic diplegia (lower limbs more affected than upper limbs)

4 = Spastic quadriplegia (upper limbs equally or more affected than lower limbs)

5 = Ataxia (coded only if it is the primary cerebral palsy type)

6 = Dyskinesia, mainly athetoid

7 = Dyskinesia, mainly dystonic

8 = Hypotonia

These codes are used singly or in combinations of up to three to describe atypical spastic distributions and/or mixed types. However, the predominant type is coded fi rst, and it is this predominant type that is used in the simple analyses by cerebral palsy type shown in this report.

Methods of ascertaining type, distribution and severity of cerebral palsy are currently being revised. Up until 2006 the Description of motor and other disabilities form was used to request clinical information from health professionals when this was not available from medical records. Severity codes were loosely defi ned according to function, though it should be noted that in most cases classifi cation of severity was derived from the subjective description recorded in the medical notes.

Since 2004 the national ACPR collaboration has been developing a system to standardise the description of cerebral palsy across Australia. This has resulted in a new form, Description of Cerebral Palsy (Appendix D), that is currently being trialled. This form uses validated measurement tools to record spasticity and functional severity of cerebral palsy: the Australian Spasticity Assessment adapted from the Modifi ed Ashworth Scale15 and shown on reverse side of form, Gross Motor Function Classifi cation System16 (Appendix E) and Manual Ability Classifi cation System17 (Appendix F). A similar 5-point scale for speech is currently being developed.


CONFIDENTIALITY OF DATA

In 1984 the Cerebral Palsy Register Advisory Committee was established in response to an increasing number of requests for access to named data. This Committee controls all matters relating to confi dentiality of Register data. Its 14 members represent all major sources of cases for the Register and also include two parent representatives. Name-identifi ed records are handled according to guidelines set down by the Advisory Committee, the Telethon Institute for Child Health Research, the Health Department of Western Australia and the NHMRC who currently fund our work. Requests for release of named data from outside researchers are referred to the Advisory Committee, and approval must be unanimous. All persons granted access to identifi ed data submit a signed declaration stating their knowledge of confi dentiality requirements and their agreement to adhere to them. Since April 1999, ethics approval has required that consent for registration be obtained before contact can be made with the children or their families.

As an ongoing project, The Western Australian Cerebral Palsy Register must seek approval annually from both the Confi dentiality of Health Information Committee of the Health Department of Western Australia and the Princess Margaret Hospital Ethics Committee.

ETHICAL CONSIDERATIONS

It is not feasible to request the permission of parents or primary care physicians to include children on the Register, primarily because the completeness of the data collection would be compromised. However, we encourage health professionals to inform parents about the Register, and some do this routinely. Efforts are also made to publicise the existence of the Register and to invite feedback from concerned individuals. To date all response has been positive.


CURRENT PROJECTS

A major case-control study of cerebral palsy in term and preterm infants born 1980 to 1995 in Western Australia is currently being analysed. This involves approximately 750 cases, about a third of whom were born preterm, 750 controls matched for year of birth, gestational age and plurality and a similar number of intrapartum stillbirths and neonatal deaths. Detailed information was collected regarding family history, mother’s medical and obstetric history, the pregnancy, the labour and delivery and the period of hospitalisation after birth with additional data on all cranial imaging and post mortems. New methods of analysing causal pathways are being applied to these data in the hope that new cases can be prevented by identifying points at which a pathway leading to cerebral palsy can be interrupted.

Other projects presently being undertaken in Western Australia:

• Trends in term and preterm cerebral palsy and neonatal mortality over time

• Mode of delivery in term singleton births resulting in perinatal death or CP

• Trends in hospitalisations of children with cerebral palsy

• Postneonatally acquired cerebral palsy in Western Australia

• The development of a system to achieve reliable descriptions of cerebral palsy, especially spastic cerebral palsy (see Appendix C).

INTERNATIONAL DEVELOPMENTS

The Western Australian Register is one of the longest-term ongoing cerebral palsy registers in existence and regularly consults with other CP research groups. The enduring spirit of co-operation amongst the cerebral palsy research community worldwide has been further fostered by international meetings to discuss methodological issues and to promote collaboration between centres18,19, including the recent workshop on Defi nition and Classifi cation of Cerebral Palsy7. Another result of such meetings was the international multicentre study of cerebral palsy in multiple births which collated data from 11 registers20.

The Surveillance of Cerebral Palsy in Europe (SCPE) is a network of 14 registers in eight European countries which commenced in 2000 with the support of the European Union5. It covers a population similar to that of the ACPR, and collaborations are anticipated.

The growing number of ongoing registers worldwide21 and the co-operation between registers refl ect the increasing importance attached to cerebral palsy research. This will enable future collaborations to overcome the problems of small numbers within subgroups of cerebral palsy. Ongoing cerebral palsy registers are essential to our ability to scientifi cally address questions about causation which are arising in our courts of law, to effectively counsel parents about risks associated with cerebral palsy and, ultimately, to prevent its occurrence.


RESULTS

The following tables and graphs vary with regard to range of birth-year cohorts and type of denominators used depending on availability of population data. While we strongly advocate the use of neonatal survivors as the appropriate denominator for calculating cerebral palsy rates since the rate of neonatal deaths can affect the CP rates, results have often been presented as rates per 1000 live births for two reasons: (1) in order to include data from earlier years when neonatal death data are not available, and (2) in order to present rates that are comparable to other data sets. The highest rates of neonatal deaths, and therefore the largest discrepancies between rates calculated by live births and neonatal survivors, occur in the low gestational age and low birth weight groups, and these are shown for comparison in Tables 3 and 4.

OVERALL BIRTH PREVALENCE

Figure 1 below shows rates per thousand live births in three-year moving averages. There has been no consistent trend in cerebral palsy birth prevalence rates in Western Australia over the period 1956-1999, but some systematic patterns are discernible. The postneonatally acquired rate appears consistently higher during the 1970s, 1980s and 1990s than it was in the late 1950s and 1960s. Excluding these cases, the CP rate appears to have risen systematically since the early 1970s. Some of this increase is accounted for by an increase in the rate of those with minimal involvement, but there is also an increase in rate of those with greater than minimal involvement from around 1.6/1000 live births in the 1970s to about 2/1000 live births from the mid-80s.

Figure 1: Rates per 1000 live births (3-year moving averages) for total CP, CP excluding postneonatal CP (PNN), and CP excluding both postneonatal and minimal CP, Western Australia, 1956-1999

0.0

0.5

1.0

1.5

2.0

2.5

3.0

1956

1959

1962

1965

1968

1971

1974

1977

1980

1983

1986

1989

1992

1995

Year of birth

Rate

per 1

000 l

ive b

irths Total CP

CP exclPNN

CP exclPNN andminimal

Note: “Minimal” cerebral palsy was included in the “mild” category prior to 1966

................................................................ REPORT OF THE WESTERN AUSTRALIAN CEREBRAL PALSY REGISTER .........................................................................13

Table 1: Cerebral palsy birth prevalence rates per 1000 live births (LB) and per 1000 neonatal survivors (NNS) in Western Australia, 1956-1999

Year of birth Live births Neonatal

survivors Total CP Rate/1000 LB 95% CI CP excl

PNNRate/1000

NNSRate/1000

LB 95% CI

1956 16916 16647 27 1.60 23 1.38 1.361957 16924 16668 31 1.83 24 1.44 1.421958 16731 16491 34 2.03 32 1.94 1.911959 17111 16875 33 1.93 29 1.72 1.691956-59 67682 66681 125 1.85 1.52 - 2.17 108 1.62 1.60 1.29 - 1.90

1960 16926 16657 44 2.60 42 2.52 2.481961 17078 16860 42 2.46 31 1.84 1.821962 17064 16817 42 2.46 41 2.44 2.401963 17290 17033 54 3.12 49 2.88 2.831964 16685 16468 40 2.40 39 2.37 2.341960-64 85043 83835 222 2.61 2.27 - 2.95 202 2.41 2.38 2.05 - 2.70

1965 16186 15941 40 2.47 37 2.32 2.291966 17007 16764 44 2.59 40 2.39 2.351967 18023 17787 55 3.05 48 2.70 2.661968 19541 19251 50 2.56 47 2.44 2.411969 20754 20432 42 2.02 39 1.91 1.881965-69 91511 90175 231 2.52 2.20 - 2.85 211 2.34 2.31 1.99 -2.62

1970 21618 21303 55 2.54 52 2.44 2.411971 24239 23934 46 1.90 42 1.75 1.731972 22177 21946 49 2.21 44 2.00 1.981973 20510 20246 38 1.85 33 1.63 1.611974 20207 19989 38 1.88 29 1.45 1.441970-74 108751 107418 226 2.08 1.81 - 2.35 200 1.86 1.84 1.58 - 2.09

1975 20338 20152 59 2.90 49 2.43 2.411976 20670 20494 57 2.76 46 2.24 2.231977 20651 20476 43 2.08 37 1.81 1.791978 20611 20456 47 2.28 35 1.71 1.701979 20634 20300 41 1.99 36 1.77 1.741975-79 102904 101878 247 2.40 2.10 - 2.70 203 1.99 1.97 1.70 - 2.24

1980 20640 20491 59 2.86 49 2.39 2.371981 22056 21936 50 2.27 41 1.87 1.861982 22209 22083 46 2.07 40 1.81 1.801983 22888 22769 71 3.10 59 2.59 2.581984 22820 22687 70 3.07 61 2.69 2.671980-84 110613 109966 296 2.68 2.37 - 2.98 250 2.27 2.26 1.98 - 2.54

1985 23165 23037 61 2.63 57 2.47 2.461986 23724 23579 55 2.32 44 1.87 1.851987 24018 23905 74 3.08 66 2.76 2.751988 25008 24884 70 2.80 59 2.37 2.361989 25392 25248 76 2.99 61 2.42 2.401985-89 121307 120653 336 2.77 2.47 - 3.07 287 2.38 2.37 2.09 - 2.64

1990 25859 25754 61 2.36 47 1.82 1.821991 24854 24771 85 3.42 77 3.11 3.101992 25192 25079 75 2.98 67 2.67 2.661993 25187 25108 61 2.42 56 2.23 2.221994 25260 25164 86 3.40 79 3.14 3.131990-94 126352 125876 368 2.91 2.62 - 3.21 326 2.59 2.58 2.30 - 2.86

1995 25285 25208 62 2.45 51 2.02 2.021996 25419 25325 69 2.71 58 2.29 2.281997 25151 25083 73 2.90 65 2.59 2.581998 25594 25528 72 2.81 66 2.59 2.581999 25614 25537 76 2.97 63 2.47 2.461995-99 127063 126681 352 2.77 2.48 - 3.06 303 2.39 2.38 2.12 - 2.65

SECTION I:

PRE- AND PERINATALLY ACQUIRED CEREBRAL PALSY


GENDER OF INFANT

Table 2 and Figure 2 show birth prevalence rates for males and females separately. As previously reported, males have been at a consistently higher risk of developing cerebral palsy with an overall (1960-1999) male:female ratio of 1.34.

These rates have been calculated by live births rather than neonatal survivors to enable the inclusion of data back to 1960; however, when calculated by neonatal survivors the difference in rates is almost negligible.

Table 2: Cerebral palsy1 birth prevalence rates per 1000 live births (LB) by gender, Western Australia, 1960 - 1999 in 5-year groups

Grouped year of birthGENDER

Males (M/F ratio) Females

1960-64 CP 130 (1.8) 72Rate/1000 LB 2.97 1.7495% CI 2 2.46 - 3.48 1.34 - 2.15

1965-69 CP 121 (1.3) 90Rate/1000 LB 2.57 2.0295% CI 2 2.11 - 3.03 1.60 - 2.44

1970-74 CP 105 (1.1) 95Rate/1000 LB 1.88 1.895% CI 2 1.52 - 2.24 1.43 - 2.16

1975-79 CP 119 (1.4) 84Rate/1000 LB 2.25 1.6895% CI 2 1.84 - 2.65 1.32 - 2.04

1980-84 CP 141 (1.3) 109Rate/1000 LB 2.47 2.0495% CI 2 2.06 - 2.88 1.66 - 2.42

1985-89 CP 160 (1.3) 127Rate/1000 LB 2.58 2.1595% CI 2 2.18 - 2.97 1.77 - 2.52

1990-94 CP 195 (1.5) 131Rate/1000 LB 3.00 2.1395% CI 2 2.58 - 3.42 177 - 2.50

1995-99 CP 164 (1.2) 139Rate/1000 LB 2.51 2.2595% CI 2 2.13 - 2.90 1.88 - 2.62

1 Excludes cerebral palsy due to postneonatal causes2 95% confi dence interval


Figure 2: Cerebral palsy* rates by gender in Western Australia, 1960-1999

0.00.51.01.52.02.53.03.5

1960-64

1965-69

1970-74

1975-79

1980-84

1985-89

1990-94

1995-99

Rate

per

1000

live b

irths

FemalesMales

BIRTH WEIGHT AND GESTATIONAL AGE

Stratifi cation of rates by birth weight in Table 3 and Figure 3a and gestational age in Table 4 and Figure 4a reveal that most of the changes in rates over time have occurred in the lower ranges of birth weight and gestational age. These dramatic rises coincide with the increased survival of very low birth weight and very preterm infants which accompanied the introduction of neonatal intensive care in Western Australia in the fi rst half of the 1970s.

As mentioned previously, Tables 3 and 4 show the difference in rates calculated using live births or neonatal survivors as the denominator. This is particularly marked in the lower birth weight and gestational age groups where neonatal survival was lowest and demonstrates the danger of underestimating the magnitude of cerebral palsy risk that can occur when calculating rates by live births.

It is also interesting to compare rates analysed by birth weight with those by gestational age. Most studies have reported cerebral palsy rates by birth weight which is more easily and reliably measured in population vital statistics and therefore more widely available, especially in earlier years. However, analysis of data by gestational age makes it possible to separate the effects of poor intrauterine growth from those of preterm birth, which are likely to have quite different causes. In Western Australia good gestational age data for the population are available only from 1980. Figure 3a presents rates in commonly reported birth weight groups and shows quite a different picture for birth cohorts after 1980 from Figure 4a which presents rates in commonly reported gestational age groups. It is also important to note the differences produced by presenting data in different ways (Figure 3a compared with 3b and Figure 4a compared with 4b).

Birth weight specifi c rates in 3-year moving averages from 1967-1999 are shown in Figure 3b (denominators for <1000g group not available before 1975), and gestational age specifi c rates in 3-year moving averages from 1980-1999 in Figure 4b.


Table 3 Birth weight specifi c cerebral palsy1 rates per 1000 live births (LB) and per 1000 neonatal survivors (NNS) in Western Australia, 1975 - 1999 in 5-year groups

Grouped year of birthBirth weight group 1975–1979 1980-1984 1985–1989 1990-1994 1995-1999

<1000g CP 4 13 13 27 33Rate/LB 11.02 35.52 25.39 58.82 63.8395% CI2 0.3 - 21.8 16.6 - 54.5 11.8 - 39.0 37.3 - 80.4 42.8 - 84.9

Rate/NNS 45.45 95.59 50.78 95.74 88.2495% CI2 1.9 - 89.0 46.2 - 145.0 23.9 - 77.7 61.4 -130.1 59.5 - 117.0

1000–1499g CP 10 26 41 35 23Rate/LB 21.51 45.61 57.42 47.55 30.4695% CI2 8.32 – 34.7 28.5 - 62.7 40.4 - 74.5 32.2 - 62.9 18.2 - 42.7

Rate/NNS 28.01 52.85 63.66 49.72 31.4695% CI2 10.9 - 45.1 33.1 - 72.6 44.8 - 82.5 33.7 - 65.8 18.8 - 44.1

All <1500g CP 14 39 54 62 56Rate/LB 16.91 41.67 44.05 51.88 44.0395% CI2 8.1 - 25.7 28.9 - 54.5 32.6 - 55.5 39.3 - 64.5 32.8 - 55.3

Rate/NNS 32.11 62.10 60.00 62.88 50.6895% CI2 15.6 - 48.7 43.2 - 80.9 44.5 - 75.5 47.7 - 78.0 37.8 - 63.6

1500–1999g CP 30 26 33 28 22Rate/LB 28.63 21.58 23.90 19.62 14.3895% CI2 18.5 - 38.7 13.4 - 29.8 15.8 - 32.0 12.4 - 26.8 8.4 - 20.3

Rate/NNS 30.90 22.39 24.77 20.06 14.6495% CI2 20.0 - 41.8 13.9 - 30.9 16.4 - 33.1 12.7 - 27.4 8.6 - 20.7

2000–2499g CP 26 23 27 26 32Rate/LB 6.94 5.71 5.91 5.33 6.3595% CI2 4.3 - 9.6 3.4 - 8.0 3.7 - 8.1 3.3 - 7.4 4.2 - 8.5

Rate/NNS 7.07 5.81 5.97 5.39 6.3995% CI2 4.4 - 9.8 3.4 - 8.2 3.7 - 8.2 3.3 - 7.5 4.2 - 8.6

All 1500–2499g CP 56 49 60 54 54Rate/LB 11.67 9.37 10.09 8.57 8.2295% CI2 8.6 - 14.7 6.7 - 12.0 7.6 - 12.6 6.3 - 10.8 6.0 - 10.4

Rate/NNS 12.05 9.57 10.24 8.68 8.2995% CI2 8.9 - 15.2 6.9 - 12.2 7.7 - 12.8 6.4 - 11.0 6.1 -10.5

2500–2999g CP 39 60 57 64 50Rate/LB 2.35 3.45 2.98 3.21 2.4595% CI2 1.6 - 3.1 2.6 - 4.3 2.2 - 3.8 2.4 - 4.0 1.8 - 3.1

3000–3499g CP 44 50 54 79 76Rate/LB 1.13 1.21 1.18 1.68 1.6395% CI2 0.8 - 1.5 0.9 - 1.5 0.9 - 1.5 1.3 - 2.1 1.3 - 2.0

3500–399 g CP 40 40 49 38 47Rate/LB 1.29 1.18 1.34 0.99 1.2395% CI2 0.9 - 1.7 0.8 - 1.6 1.0 - 1.7 0.7 - 1.3 0.9 - 1.6

>=4000g CP 10 12 13 29 20Rate/LB 0.94 1.02 1.02 2.12 1.4695% CI2 0.4 - 1.5 0.4 - 1.6 0.5 - 1.6 1.4 - 2.9 0.8 - 2.1

All >=2500g CP 133 162 173 210 193Rate/LB 1.37 1.55 1.52 1.77 1.6295% CI2 1.1 - 1.6 1.3 - 1.8 1.3 - 1.7 1.5 - 2.0 1.4 - 1.9

Rate/NNS 1.37 1.55 1.52 1.77 1.6295% CI2 1.1 - 1.6 1.3 -1.8 1.3 - 1.8 1.5 - 2.0 1.4 - 1.9

1 Excludes cerebral palsy due to postneonatal causes2 95 % confi dence interval


Figure 3a Birth weight specifi c cerebral palsy1 rates per 1000 neonatal survivors, Western Australia, 1975-1999, in 5-year groups

0 10 20 30 40 50 60 70 80 90

100

1975–1979 1980-1984 1885–1989 1990-1994 1995-1999 Grouped year of birth

<1000g

1000-1499g

1 Excludes cerebral palsy due to postneonatal causes

>=2500g 1500-2499g Ra

te pe

r 100

0 neo

natal

surv

ivors

Figure 3b Birth weight specifi c cerebral palsy1 rates per 1000 neonatal survivors (3-year moving averages), Western Australia 1966-1999

0

10

20

30

40

50

60

70

80

90

1966-6

8

1969-7

1

1972-7

4

1975-7

7

1978-8

0

1981-8

3

1984-8

6

1987-8

9

1990-9

2

1993-9

5

1996-9

8

Grouped year of birth

Rate

per

1000 n

eo

nata

l su

rviv

ors

<1500g

1500-2499g

>=2500g



Table 4: Gestational age specifi c cerebral palsy1 rates per 1000 live births (LB) and per 1000 neonatal survivors (NNS) in Western Australia, 1980 - 1999 in 5-year groups

Grouped year of birthGestational age group 1980 – 1984 1885 – 1989 1990 – 1994 1995 - 1999

20-27 wks CP 11 18 33 30Rate/LB 24.61 32.43 62.38 54.8495% CI2 10.3 - 39.0 17.7 - 47.2 41.8 - 83.0 35.8 - 73.9Rate/NNS 53.66 64.29 100.00 76.9295% CI2 22.8 - 84.5 35.6 - 93.0 67.6 - 132.4 50.5 - 103.4


All <= 31 wks CP 52 66 78 63Rate/LB 33.25 33.76 39.00 31.6195% CI2 24.4 - 42.1 25.8 - 41.8 30.5 - 47.5 23.9 - 39.3Rate/NNS 41.63 41.33 44.50 35.0495% CI2 30.6 - 52.7 31.6 - 51.1 34.8 - 54.2 26.5 - 43.5


All > 37 wks CP 163 177 208 197Rate/LB 1.60 1.59 1.80 1.7095% CI2 1.4 - 1.9 1.4 - 1.8 1.6 - 2.0 1.5 - 1.9Rate/NNS 1.60 1.59 1.80 1.7095% CI2 1.4 - 1.9 1.4 - 1.8 1.6 - 2.1 1.5 - 1.9



Figure 4a: Gestational age specifi c cerebral palsy1 rates per 1000 neonatal survivors in Western Australia, 1980 - 1999

0102030405060708090

100

1980 – 1984 1885 – 1989 1990 – 1994 1995 - 1999


Rat

e/10

00 n

eona

tal s

urvi

vors


32-36w>=37w

20-27w

28-31w

Figure 4b: Gestational age specifi c cerebral palsy1 rates per 1000 neonatal survivors (3-year moving averages) Western Australia, 1980 - 1999

020

4060

80100

120140

1980

-82

1981

-83

1982

-84

1983

-85

1984

-86

1985

-87

1986

-88

1987

-89

1988

-90

1989

-91

1990

-92

1991

-93

1992

-94

1993

-95

1994

-96

1995

-97

1996

-98

1997

-99

20-27w28-31w32-36w37w+

Rate

per 1

000 n

eona

tal su

rvivo

rs



PLURALITY

Rates of cerebral palsy by singleton and multiple births are shown in Table 5a and Figure 5a. While there has been little change in singleton rates over the period 1960-1999, rates in multiple births have increased over the same time. This coincides with the rise in the rates of multiple births observed both here (Figure 5b), and elsewhere thought to be due mainly to the increasing use of fertility treatments20.

Table 5a: Cerebral palsy1 birth prevalence rates per 1000 live births (LB) and neonatal survivors (NNS) (data not available before 1970) by plurality, Western Australia, 1960-1999 in 5-year groups

PluralityGrouped year of birth Singleton All Multiple

1960-64 CP 193 9Rate/LB 2.31 5.5095% CI2 2.0 - 2.6 1.9 - 9.1% all CP 95.5 4.5


1970-74 CP 181 18Rate/LB 1.70 8.8695% CI2 1.5 - 1.9 4.8 - 12.9Rate/NNS 1.71 9.6795% CI2 1.5 - 2.0 5.2 - 14.1% all CP 91.0 9.0








Figure 5a Cerebral palsy1 rates per 1000 live births by plurality, Western Australia, 1960-1999

0

2

4

68

10

12

14

1960-64 1965-69 1970-74 1975-79 1980-84 1985-89 1990-94 1995-99


Rate

per 1

000 l

ive bi

rths

Singletons

Multiples

Figure 5b Twin and triplet rates, Western Australia 1960-1999

0

2

4

6

8

10

12

14

16

Twins Triplets + Plurality

Twin

rate

/ 10

00 p

regn

ancie

s Tr

iplet

rate

/ 10

,000

pre

gnan

cies 1960-64

1965-691970-741975-791980-841985-891990-941995-99


Tables 5b and 5c show rates for singleton and multiple births stratifi ed by birth weight and gestational age respectively. While cerebral palsy rates do not vary signifi cantly by plurality in the low birth weight and very preterm birth strata, they are signifi cantly higher in normal birth weight and term-born multiples. Therefore the higher rate in multiples occurs both because a greater proportion of multiple births are born low birth weight and very preterm when risks are higher, and because term multiples have higher rates of cerebral palsy than term singletons.

Table 5b: Cerebral palsy1 birth prevalence rates per 1000 neonatal survivors (NNS) by plurality and birth weight, Western Australia, 1980 - 1999 in 5-year groups

PluralityGrouped year of birth Birth weight group Singleton Multiple1980-84 <1500 g CP 32 7

Rate/NNS 61.42 65.4295% CI2 40.8 - 82.0 18.6 - 112.3

1500-2499 g CP 41 8Rate/NNS 9.73 8.8395% CI2 6.8 - 12.7 2.7 - 14.9

>2500 g CP 156 6Rate/NNS 1.51 4.9695% CI2 1.3 - 1.8 1.0 - 8.9

1985-89 <1500 g CP 43 11Rate/NNS 62.87 50.9395% CI2 44.7 - 81.1 21.6 - 80.2

1500-2499 g CP 47 13Rate/NNS 10.29 10.0995% CI2 7.4 - 13.2 4.6 - 15.6

>2500 g CP 159 14Rate/NNS 1.41 9.6495% CI2 1.2 - 1.6 4.6 - 14.7

1990-94 <1500 g CP 47 15Rate/NNS 66.10 54.5595% CI2 47.8 - 84.4 27.7 - 81.4

1500-2499 g CP 40 14Rate/NNS 8.27 10.1295% CI2 5.7 - 10.8 4.8 -15.4

>2500 g CP 206 4Rate/NNS 1.76 2.5995% CI2 1.5 - 2.0 0.06 - 5.1

1995-99 <1500 g CP 38 18Rate/NNS 47.68 58.4495% CI2

32.9 - 62.5 32.2 - 84.6

1500-2499 g CP 48 6Rate/NNS 9.70 3.8595% CI2

7.0 - 12.4 0.8 - 6.9

>2500 g CP 184 9Rate/NNS 1.57 5.0695% CI2

1.3 - 1.8 1.8 - 8.4



Table 5c: Cerebral palsy1 birth prevalence rates per 1000 neonatal survivors (NNS) by plurality and gestational age, Western Australia, 1980-1999 in 5-year groups

Grouped year of birth Gestational age group Singletons Multiples

1980-84 20-31w CP 44 8Rate/NNS 58.05 60.6195% CI2 41.4 - 74.7 19.9 - 101.3

32-36w CP 28 7Rate/NNS 4.81 8.9395% CI2 3.0 - 6.6 2.3 - 15.5

>=37w CP 157 6Rate/NNS 1.57 4.5995% CI2 1.3 - 1.8 0.9 - 8.3

1985-89 20-31w CP 52 14Rate/NNS 57.97 65.4295% CI2 42.7 - 73.3 32.3 - 98.6

32-36w CP 34 10Rate/NNS 5.11 8.5295% CI2 3.4 - 6.82 3.3 - 13.8

>=37w CP 163 14Rate/NNS 1.49 9.0195% CI2 1.3 - 1.7 4.3 - 13.7

1990-94 20-31w CP 59 19Rate/NNS 61.97 58.8295% CI2 46.7 - 77.3 33.2 - 84.5

32-36w CP 33 7Rate/NNS 4.58 5.1795% CI2 3.0 - 6.1 1.4 - 9.0

>=37w CP 201 7Rate/NNS 1.76 4.6095% CI2 1.5 - 2.0 1.2 - 8.0

1995-99 20-31w CP 44 19Rate/NNS 44.04 58.2895% CI2 31.3 - 56.8 32.9 - 83.7

32-36w CP 37 6Rate/NNS 5.18 3.6795% CI2 3.5 - 6.8 0.7 - 6.6

>=37w CP 189 8Rate/NNS 1.66 4.8195% CI2 1.4 - 1.9 1.5 - 8.1



AREA OF RESIDENCE

Cerebral palsy birth prevalence rates by metropolitan or rural residence at time of birth are shown in Figure 6 and Table 6a. Metropolitan is defi ned as the Perth and surrounding hills area and rural as any other place in the State. Although towns such as Bunbury and Geraldton are quite large, the only neonatal intensive care units are located in Perth.

The lower rates seen in the rural group prior to 1975 are likely to be due to under ascertainment of country cases in the earlier years of the Register. The Rural Paediatric Service which is an important source of rural cases was not accessed until 1984, and although cases were notifi ed retrospectively at that time, this service would not have covered teenagers older than 15 years or adults. Also, because address at time of birth was not always available for the early cases, it is likely that some older individuals with more severe forms of cerebral palsy who had come to live in hostels in Perth were included in the metropolitan group.

Rates for the metropolitan and rural groups by gestational age shown in Table 6b show little difference between areas.

Figure 6 Cerebral palsy1 birth prevalence rates per 1000 live births by metropolitan or rural residence at time of birth, Western Australia, 1960-1999

0.0

0.51.0

1.5

2.0

2.53.0

3.5

1960-64 1965-69 1970-74 1975-79 1980-84 1985-89 1990-94 1995-99


Rate

per 1

000 l

ive bi

rths


Metro

Rural


Table 6a: Cerebral palsy1 birth prevalence rates per 1000 live births (LB) by metropolitan or rural residence at time of birth, Western Australia, 1960-1999 in 5-year groups

Area of residenceGrouped year of birth Metropolitan Rural











Table 6b: Gestational age specifi c cerebral palsy1 rates per 1000 neonatal survivors (NNS) by metropolitan or rural residence at time of birth, Western Australia, 1980 - 1999 in 5-year groups

Area of residenceGestational age group Grouped year of birth Metropolitan Rural

<=31 weeks 1980-84 CP 36 16Rate/NNS 61.54 52.8195% CI2 42.1 - 81.0 27.6 - 78.0

1985-89 CP 47 19Rate/NNS 63.86 50.9495% CI2 46.2 - 81.5 28.6 - 73.3

1990-94 CP 50 27Rate/NNS 57.47 67.0095% CI2 42.0 - 72.9 42.6 - 91.4

1995-99 CP 49 13Rate/NNS 53.26 32.7595% CI2 38.8 - 67.8 15.2 - 50.3

32-36 weeks 1980-84 CP 21 14Rate/NNS 4.82 6.2595% CI2 2.8 - 6.9 3.0 - 9.5

1985-89 CP 36 8Rate/NNS 6.86 3.1095% CI2 4.6 - 9.1 1.0 - 5.3

1990-94 CP 29 11Rate/NNS 4.93 4.1195% CI2 3.1 - 6.7 6.7 - 6.5

1995-99 CP 30 12Rate/NNS 5.00 4.3295% CI2 3.2 - 6.8 1.9 - 6.8

>37 weeks 1980-84 CP 109 54Rate/NNS 1.62 1.5795% CI2 1.3 - 1.9 1.2 - 2.0

1985-89 CP 116 61Rate/NNS 1.54 1.7095% CI2 1.3 - 1.8 1.3 - 2.1

1990-94 CP 129 80Rate/NNS 1.63 2.2295% CI2 1.4 - 1.9 1.7 - 2.7

1995-99 CP 138 60Rate/NNS 1.71 1.7295% CI2 1.4 - 2.0 1.3 - 2.2



INDIGENOUS STATUS OF MOTHER

Population data by Indigenous status are available only from 1980 onwards. Cerebral palsy rates in Western Australia have been consistently higher in the Indigenous population as seen in Table 7 and Figure 7.

Table 7: Cerebral palsy1 birth prevalence rates per 1000 live births (LB) and neonatal survivors (NNS) by Indigenous status of mother, Western Australia, 1980-1999 in 5-year groups

Race of MotherGrouped year of birth Non-Indigenous Indigenous






Figure 7: Cerebral palsy1 birth rates per 1000 live births by Indigenous status of mother, Western Australia, 1980-1999

0.00.51.01.52.02.53.03.54.04.5

1980-84 1985-89 1990-94 1995-99

Grouped year of birth1 Excludes cerebral palsy due to postneonatal causes

Indigenous

Non-Indigenous

Rate

per 1

000 l

ive bi

rths


AGE OF MOTHER

Cerebral palsy rates by age of mother are shown in Figure 8a in 10-year groups and Table 8 in 5-year groups.

Increased rates in the earliest compared with the most recent year groups in mothers aged <20 years could refl ect less favourable health conditions in the smaller proportion of women who are now having babies in their teenage years.

Lower rates in mothers >40 years more recently may, conversely, be due to the more favourable conditions of this group which would now include a larger proportion of socially advantaged women who have deliberately delayed child bearing, including those who have used assisted conception. It also includes a larger proportion of women who have had fewer previous births, high parity being known to be associated with a higher risk of cerebral palsy (see Table 9 and Figure 9). While numbers in the group >=40 years are very small, the increase in the 1990-99 period during which assisted conception had become commonplace should prompt an investigation into the occurrence of cerebral palsy following the use of assisted reproductive technology.

Figure 8a: Cerebral palsy1 birth rates per 1000 live births by age of mother at time of birth, Western Australia, 1960 – 1999

0.00.51.01.52.02.53.03.54.04.5

<20 20-24 25-29 30-34 35-39 >=40

Age of Mother (years)

Rate

per 1

000 l

ive bi

rths

1960-691970-791980-891990-99


Table 8: Cerebral palsy1 birth prevalence rates per 1000 live births by age of mother at time of birth, Western Australia, 1960 – 1999 in 5-year groups

Age of Mother (years)Grouped year of birth <20 20-24 25-29 30-34 35-39 >=40

1960-64 CP 21 49 55 38 26 10Rate 2.93 1.71 2.19 2.58 3.60 4.4995% CI2 1.7 - 4.2 1.2 – 2.2 1.6 – 2.8 1.8 – 3.4 2.2 – 5.0 1.7 – 7.3% all CP 10.4 24.3 27.2 18.8 12.9 5.0

1965-69 CP 21 62 60 39 15 6Rate 1.90 1.94 2.19 2.95 2.52 3.2395% CI2 1.1 – 2.7 1.5 – 2.4 1.6 – 2.7 2.0 – 3.9 1.3 – 3.8 0.7 – 5.8% all CP 10.0 29.4 28.4 18.5 7.1 2.8

1970-74 CP 33 61 60 26 12 3Rate 2.52 1.52 1.72 1.81 2.36 2.2795% CI2 1.7 – 3.4 1.1 – 1.9 1.3 – 2.2 1.1 – 2.5 1.0 – 3.7 -0.3 – 4.8% all CP 16.5 30.5 30.0 13.0 6.0 1.5

1975-79 CP 17 66 64 36 9 6Rate 1.71 1.87 1.70 2.36 2.30 8.3895% CI2 0.9 – 2.5 1.4 – 2.3 1.3 – 2.1 1.6 – 3.1 0.8 – 3.8 1.7 – 15.1% all CP 8.4 32.5 31.5 17.7 4.4 3.0

1980-84 CP 16 75 90 47 20 2Rate 1.95 2.27 2.14 2.21 3.84 2.5695% CI2 1.0 - 2.9 1.8 – 2.8 1.7 – 2.6 1.6 - 2.8 2.2 – 5.5 -1.0 – 6.1% all CP 6.4 30.0 36.0 18.8 8.0 0.8

1985-89 CP 27 59 115 65 19 1Rate 3.51 2.05 2.45 2.29 2.28 0.9295% CI2 2.2 - 4.8 1.5 - 2.6 2.0 - 2.9 1.7 - 2.9 1.3 – 3.3 -0.9 – 2.7% all CP 9.4 20.6 40.1 22.6 6.6 0.3

1990-94 CP 31 77 97 87 27 6Rate 3.91 2.97 2.21 2.48 2.32 3.3795% CI2 2.5 - 5.3 2.3 - 3.6 1.8 - 2.7 2.0 - 3.0 1.5 - 3.2 0.7 - 6.1% all CP 9.5 23.6 29.8 26.7 8.3 1.8

1995-99 CP 24 45 90 84 55 5Rate 3.20 1.97 2.18 2.25 3.52 2.0395% CI2 1.9 - 4.5 1.4 - 2.6 1.7 - 2.6 1.8 - 2.7 2.6 - 4.5 0.3 - 3.8% all CP 7.9 14.9 29.7 27.7 18.2 1.7



The more recent shift in distribution of maternal age from younger to older ages that occurred amongst all births in Western Australia is seen also in the maternal age distribution of cerebral palsy as shown in Figures 8b and 8c which compare birth years 1975-79 with birth years 1995-99.

Figure 8b: Distribution of cerebral palsy1 by age of mother, Western Australia, 1975-79 compared with 1995-99

05

10152025303540

<20 20-24 25-29 30-34 35-39 >=40Age of Mother (years)

% of

all c

ereb

ral p

alsy

1975-791995-99

Excludes cerebral palsy due to postneonatal causes

Figure 8c: Distribution of live births by age of mother, Western Australia, 1975-79 compared with 1995-99

05

10152025303540

<20 20-24 25-29 30-34 35-39 >=40

Perc

ent o

f all l

ive bi

rths

1975-79

1995-99


PREVIOUS BIRTHS

Table 9 shows cerebral palsy rates by the number of mother’s previous births in 5-year groups from 1970 to 1999. As previously reported, these rates are highest in the groups with 4 and 5 or more previous births. The effects of maternal age and parity are interdependent. Those with high parity are likely also to be of advanced age and have higher rates of cerebral palsy as shown in Table 8 and Figure 8a. As observed in the high maternal age groups, these rates have also declined in the high parity groups, once again refl ecting the changing risk characteristics of these groups in the more recent time periods when delayed child bearing has been more prevalent (Figure 9).

Table 9: Cerebral palsy1 birth prevalence rates per 1000 live births by previous births to mother, Western Australia, 1960 – 1999 in 5-year groups

Number of previous births to motherGrouped year of birth 0 1 2 3 4 >=5

1970-74 CP 91 54 24 10 7 11Rate 2.50 1.75 1.48 1.44 2.71 4.7495% CI2 2.0 - 3.0 1.3 - 2.2 0.9 - 2.1 0.6 - 2.3 0.7 - 4.7 2.0 - 7.5% all CP 45.5 27.0 12.0 5.0 3.5 5.5

1975-79 CP 82 66 29 9 9 5Rate 2.30 2.13 1.89 1.84 6.36 5.0595% CI2 1.8 - 2.8 1.6 - 2.6 1.2 - 2.6 0.6 - 3.0 2.2 - 10.5 0.6 - 9.5% all CP 40.4 32.5 14.3 4.4 4.4 2.5

1980-84 CP 102 74 42 23 7 2Rate 2.39 2.04 2.16 3.31 3.28 1.4295% CI2 1.9 - 2.9 1.6 - 2.5 1.5 - 2.8 2.0 - 4.7 0.9 - 5.7 0 - 3.4% all CP 40.8 29.6 16.8 9.2 2.8 0.8

1985-89 CP 117 85 44 21 12 8Rate 2.49 2.10 2.03 2.66 4.74 5.1495% CI2 2.0 - 2.9 1.7 - 2.5 1.4 - 2.6 1.5 - 3.8 2.1 - 7.4 1.6 - 8.7% all CP 40.8 29.6 15.3 7.3 4.2 2.8

1990-94 CP 152 92 47 21 6 7Rate 3.07 2.21 2.13 2.49 2.07 3.8695% CI2 2.6 - 3.6 1.8 - 2.7 1.5 - 2.7 1.4 - 3.6 0.4 - 3.7 1.0 - 6.7% all CP 46.6 28.2 14.4 6.4 1.8 2.1

1995-99 CP 139 77 44 26 10 7Rate 2.72 1.82 2.12 3.32 3.33 3.4795% CI2 2.3 - 3.2 1.4 - 2.2 1.5 - 2.8 2.0 - 4.6 1.3 - 5.4 0.9 - 6.0% all CP 45.9 25.4 14.5 8.6 3.3 2.3


Figure 9: Cerebral palsy1 rates per 1000 live births by previous births to mother, Western Australia, 1960 – 1999

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

4.5

5.0

0 1 2 3 4 >=5

Previous number of births to mother

Rate

per

1000 liv

e b

irth

s

1970-79

1980-89

1990-99



SEVERITY OF CEREBRAL PALSY

Overall minimal and mild cerebral palsy accounts for almost half of all cases with moderate and severe accounting for about a quarter each (Figure 10a). Rates by severity of the motor impairment are shown in Figure 10b and Tables 10a and 10b.

Figure 10a: Cerebral palsy1 proportions by severity of cerebral palsy, Western Australia, 1975 - 1999 combined

Minimal CP14%

Mild CP33% Moderate CP

28%

Severe CP25%


Table 10a: Cerebral palsy1 birth prevalence rates per 1000 live births (LB) by severity of cerebral palsy, Western Australia, 1975 - 1999 in 5-year groups

CP SeverityGrouped year of birth Minimal Mild Moderate Severe

1975-79 CP 20 83 63 36Rate/LB 0.19 0.81 0.61 0.3595% CI2 0.1 - 0.3 0.6 - 1.0 0.5 - 0.8 0.2 - 0.5% of all CP 9.9 40.9 31.0 17.7







Figure 10b: Cerebral palsy1 rates per 1000 live births by severity of motor impairment, Western Australia, 1975 - 1999

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

Minimal Mild Moderate Severe

Rate

per 1

000 l

ive bi

rths

Severity of cerebral palsy


1975-79

1980-84

1985-89

1990-94

1995-99

Table 10b: Cerebral palsy1 birth prevalence rates per 1000 neonatal survivors (NNS) by severity of cerebral palsy and gestational age (GA), Western Australia, 1980 - 1999 in 5-year groups

CP SeverityGrouped year of birth GA Group Minimal/Mild Moderate Severe

1980-84 <=31w CP 22 17 13Rate/NNS 24.72 19.10 14.6195% CI2 14.5 - 34.9 10.1 - 28.1 6.7 - 22.5

32-36w CP 11 19 5Rate/NNS 1.66 2.88 0.7695% CI2 0.7 - 2.7 1.6 - 4.2 0.1 - 1.4

>=37w CP 73 41 48Rate/NNS 0.72 0.40 0.4795% CI2 0.6 - 0.9 0.3 - 0.5 0.3 - 0.6

1985-89 <=31w CP 29 24 13Rate/NNS 26.10 21.60 11.7095% CI2 16.7 - 35.5 13.1 - 30.2 5.4 - 18.0

32-36w CP 22 12 10Rate/NNS 2.81 1.53 1.2895% CI2 1.6 - 4.0 0.7 - 2.4 0.5 - 2.1

>=37w CP 85 42 50Rate/NNS 0.76 0.38 0.4595% CI2 0.6 - 0.9 0.3 - 0.5 0.3 - 0.6

1990-94 <=31w CP 46 21 11Rate/NNS 36.08 16.47 8.6395% CI2 25.8 - 46.3 9.5 - 23.5 3.6 - 13.7

32-36w CP 17 13 10Rate/NNS 1.99 1.52 1.1795% CI2 1.0 - 2.9 0.7 - 2.3 0.4 - 1.9

>=37w CP 88 44 75Rate/NNS 0.76 0.38 0.6595% CI2 0.6 - 0.9 0.3 - 0.5 0.5 - 0.8

1995-99 <=31w CP 34 21 8Rate/NNS 25.66 15.85 6.0495% CI2 17.2 - 34.2 9.1 - 22.6 1.9 - 10.2

32-36w CP 22 11 10Rate/NNS 2.51 1.25 1.1495% CI2 1.5 - 3.6 0.5 - 2.0 0.4 - 1.8

>=37w CP 90 54 53Rate/NNS 0.78 0.47 0.4695% CI2 0.6 - 0.9 0.3 - 0.6 0.3 - 0.6



Figure 10c: Cerebral palsy1 rates by severity of cerebral palsy and gestational age at birth, Western Australia, 1980-1995

0

5

10

15

20

25

30

35

40

Minimal/Mild Moderate Severe


Rate

/1000 n

eo

nata

l su

rviv

ors

1980-84

1985-89

1990-94

1995-99

Gestational age <=31 weeks

0.0

0.5

1.0

1.5

2.0

2.5

3.0



Rate

/100

0 ne

onat

al s

urvi

vors

1980-841985-891990-941995-99

Gestational age 32-36 weeks

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8


1980-84

1985-89

1990-94

1995-99

Gestational age >=37 weeks


Rate

/1000 n

eo

nata

l su

rviv

ors


TYPE OF CEREBRAL PALSY

Proportions of the different types of cerebral palsy, 1975-99 combined, are shown in the pie chart on p33 (Figure 11a). Rates by spastic distribution and non-spastic cerebral palsy types are shown in Tables 11a and 11b and illustrated in Figures 11b and 11c.

Table 11a: Spastic cerebral palsy1 birth prevalence rates per 1000 live births (LB), Western Australia, 1970 - 1999 in 5-year groups

Spastic CP type2

Grouped year of birth Hemiplegia Diplegia Quadriplegia All spastic CP

1970-74 CP 56 80 28 164Rate/LB 0.51 0.74 0.26 1.5195% CI3 0.4 - 0.7 0.6 - 0.9 0.2 - 0.4 1.3 - 1.7% all CP 28.0 40.0 14.0 82.0






1 Excludes cerebral palsy due to postneonatal causes2 Predominant cerebral palsy type; includes cases with lesser degree of other spastic and/or non-spastic types3 95% confi dence interval


Table 11b: Non-spastic cerebral palsy1 birth prevalence rates per 1000 live births (LB), Western Australia, 1970 - 1999 in 5-year groups

Cerebral palsy type2

Grouped year of birth Ataxia Dyskinesia All non-spastic CP3

1970-74 CP 18 16 36Rate/LB 0.17 0.15 0.3395% CI4 0.1 - 0.2 0.1 - 0.2 0.2 - 0.4% all CP 9.0 8.0 18.0






1 Excludes cerebral palsy due to postneonatal causes2 Predominant cerebral palsy type; includes cases with a lesser degree of spastic types3 Includes hypotonic CP4 95% confi dence interval

Figure 11a: Cerebral palsy1 proportions by predominant type, Western Australia, 1975-1999 combined

Spastic hemiplegia36%

Spastic diplegia32%

Spastic quadriplegia14%

Ataxic CP8%

Dyskinetic CP9%

Hypotonic CP1%



Figure 11b: Spastic cerebral palsy1rates per 1000 live births, Western Australia, 1970-1999

0.0

0.5

1.0

1.5

2.0

Hemiplegia Diplegia Quadriplegia All spastic CP

Type of spastic cerebral palsy

Rate

per

1000 liv

e b

irth

s

1970-79

1980-89

1990-99


Figure 11c: Non-spastic cerebral palsy1rates per 1000 live births, Western Australia, 1970-1999

0.0

0.5

1.0

1.5

2.0

Ataxia Dyskinesia All non-spastic CP

Type of cerebral palsy

Ra

te p

er

10

00

liv

e b

irth

s

1970-79

1980-89

1990-99



Birth weight specifi c (Tables 12a, 12b) and gestational age specifi c (Tables 13a, 13b) rates by CP type are shown below. The latter are graphed in Figures 11a-d, and rates by predominant cerebral palsy type and severity are shown in Table 14.

Table 12a: Spastic cerebral palsy1 birth prevalence rates per 1000 neonatal survivors (NNS) by spastic type and birth weight, Western Australia, 1975 - 1999 in 5-year groups

Spastic CP type2

BW group Grouped year of birth Hemiplegia Diplegia Quadriplegia All spastic CP

<1500g 1975-79 CP 5 8 0 13Rate/NNS 11.47 18.35 29.8295% CI3 1.5 - 21.5 5.8 - 31.0 13.9 - 45.8

1980-84 CP 16 15 7 38Rate/NNS 25.48 23.89 11.15 60.5195% CI3 13.2 - 37.8 11.9 - 35.8 2.9 - 19.4 41.9 - 79.2

1985-89 CP 19 29 5 53Rate/NNS 21.11 32.22 5.56 58.8995% CI3 11.7 - 30.5 20.7 - 43.8 0.7 - 10.4 43.5 - 74.3

1990-94 CP 28 29 3 60Rate/NNS 28.40 29.41 3.04 60.8595% CI3 18.0 - 38.8 18.9 - 40.0 0 - 6.5 45.9 - 75.8

1995-99 CP 20 29 3 52Rate/NNS 18.10 26.24 2.71 47.0695% CI3 10.2 - 26.0 16.8 - 35.7 0 - 5.8 34.6 - 59.5

1500-2499g 1975-79 CP 21 23 7 51Rate/NNS 4.52 4.95 1.51 10.9795% CI3 2.6 - 6.5 2.9 - 7.0 0.4 - 2.6 7.9 - 14.0

1980-84 CP 13 23 6 42Rate/NNS 2.54 4.49 1.17 8.2095% CI3 1.2 - 3.9 2.7 - 6.3 0.2 - 2.1 5.7 - 10.7

1985-89 CP 15 25 9 49Rate/NNS 2.56 4.27 1.54 8.3795% CI3 1.3 - 3.9 2.6 - 5.9 0.5 - 2.5 6.0 - 10.7

1990-94 CP 20 18 7 45Rate/NNS 3.22 2.89 1.13 7.2495% CI3 1.8 - 4.6 1.6 - 4.2 0.3 - 2.0 5.1 - 9.3

1995-99 CP 14 28 4 46Rate/NNS 2.15 4.30 0.61 7.0795% CI3 1.0 - 3.3 2.7 - 5.9 0.01 - 1.2 5.0 - 9.1

>=2500g 1975-79 CP 54 41 17 112Rate/NNS 0.56 0.42 0.18 1.1695% CI3 0.4 - 0.7 0.3 - 0.6 0.1 - 0.3 0.9 - 1.4

1980-84 CP 69 33 30 132Rate/NNS 0.66 0.32 0.29 1.2795% CI3 0.5 - 0.8 0.2 - 0.4 0.2 - 0.4 1.1 - 1.5

1985-89 CP 55 39 36 130Rate/NNS 0.48 0.34 0.32 1.1495% CI3 0.4 - 0.6 0.2 - 0.5 0.2 - 0.4 0.9 - 1.3

1990-94 CP 66 47 41 154Rate/NNS 0.56 0.40 0.35 1.3095% CI3 0.4 - 0.7 0.3 - 0.5 0.2 - 0.5 1.1 - 1.5

1995-99 CP 74 45 17 136Rate/NNS 0.62 0.38 0.14 1.1495% CI3 0.5 - 0.8 0.3 - 0.5 0.1 - 0.2 1.0 - 1.3



Table 12b: Non-spastic cerebral palsy1 birth prevalence rates per 1000 neonatal survivors (NNS) by cerebral palsy type and birth weight, Western Australia, 1980-1999

Non-spastic CP type2

BW group Grouped year of birth Ataxia Dyskinesia All non-spastic CP3

<1500g 1975-79 CP 0 1 1Rate/NNS 2.29 2.2995% CI4 0 - 6.8 0 - 6.8

1980-84 CP 1 0 1Rate/NNS 1.59 1.5995% CI4 0 - 4.7 0 - 4.7

1985-89 CP 0 1 2Rate/NNS 1.11 2.2295% CI4 0 - 3.3 0 - 5.3

1990-94 CP 1 1 2Rate/NNS 1.01 1.01 2.0395% CI4 0 - 3.0 0 - 3.0 0 - 4.8

1995-99 CP 2 2 4Rate/NNS 1.81 1.81 3.6295% CI4 0 - 4.3 0 - 4.3 0.1 - 7.1

1500-2499g 1975-79 CP 2 3 5Rate/NNS 0.43 0.65 1.0895% CI4 0 - 1.0 0 - 1.4 0.1 - 2.0

1980-84 CP 3 3 7Rate/NNS 0.59 0.59 1.3795% CI4 0 - 1.3 0 - 1.3 0.4 - 2.4

1985-89 CP 4 5 10Rate/NNS 0.68 0.85 1.7195% CI4 0.01 - 1.35 0.1 - 1.6 0.7 - 2.8

1990-94 CP 2 6 9Rate/NNS 0.32 0.96 1.4595% CI4 0 - 0.8 0.2 - 1.7 0.5 - 2.4

1995-99 CP 4 3 8Rate/NNS 0.61 0.46 1.2395% CI4 0.01 - 1.2 0 - 1.0 0.4 - 2.1

>=2500g 1975-79 CP 10 9 20Rate/NNS 0.10 0.09 0.2195% CI4 0.04 - 0.2 0.03 - 0.2 0.1 - 0.3

1980-84 CP 12 18 30Rate/NNS 0.12 0.17 0.2995% CI4 0.05 - 0.2 0.1 - 0.3 0.2 - 0.4

1985-89 CP 21 18 39Rate/NNS 0.18 0.16 0.3495% CI4 0.1 - 0.3 0.1 - 0.2 0.2 - 0.5

1990-94 CP 25 26 56Rate/NNS 0.21 0.22 0.4795% CI4 0.1 - 0.3 0.1 - 0.3 0.4 - 0.6

1995-99 CP 21 33 57Rate/NNS 0.18 0.28 0.4895% CI4 0.1 - 0.3 0.2 - 0.4 0.4 - 0.6

1 Excludes cerebral palsy due to postneonatal causes2 Predominant cerebral palsy type; includes cases with lesser degree of spastic types3 Includes hypotonic cerebral palsy4 95% confi dence interval


Table 13a: Spastic cerebral palsy1 birth prevalence rates per 1000 live births (LB) by spastic type and gestational age, Western Australia, 1980 - 1999 in 5-year groups

Spastic CP type2

GA group Grouped year of birth Hemiplegia Diplegia Quadriplegia All spastic CP

20-31w 1980-84 CP 19 25 7 51Rate/NNS 21.35 28.09 7.87 57.3095% CI3 11.9 - 30.8 17.2 - 39.0 2.1 - 13.7 42.0 - 72.6

1985-89 CP 19 36 9 64Rate/NNS 17.10 32.40 8.10 57.6195% CI3 9.5 - 24.7 22.0 - 42.8 2.8 - 13.4 43.9 - 71.3

1990-94 CP 37 37 2 76Rate/NNS 29.02 29.02 1.57 59.6195% CI3 19.8 - 38.2 19.8 - 38.2 0 - 3.7 47.6 - 72.6

1995-99 CP 20 34 4 58Rate/NNS 15.09 25.66 3.02 43.7795% CI3 8.5 - 21.7 17.2 - 34.2 0.1 - 6.0 32.8 - 54.8

32-36w 1980-84 CP 15 13 6 34Rate/NNS 2.27 1.97 0.91 5.1595% CI3 1.1 - 3.4 0.9 - 3.0 0.2 - 1.6 3.4 - 6.9

1985-89 CP 16 18 5 39Rate/NNS 2.04 2.30 0.64 4.9895% CI3 1.0 - 3.0 1.2 - 3.4 0.1 - 1.2 3.4 - 6.5

1990-94 CP 14 10 2 26Rate/NNS 1.63 1.17 0.23 3.0495% CI3 0.8 - 2.5 0.4 - 1.9 0 - 0.6 1.9 - 4.2

1995-99 CP 11 22 5 38Rate/NNS 1.25 2.51 0.57 4.3395% CI3 0.5 - 2.0 1.5 - 3.6 0.1 - 1.1 3.0 - 5.7

>=37w 1980-84 CP 64 33 30 127Rate/NNS 0.63 0.32 0.30 1.2595% CI3 0.5 - 0.8 0.2 - 0.4 0.2 - 0.4 1.0 - 1.5

1985-89 CP 54 39 36 129Rate/NNS 0.49 0.35 0.32 1.1695% CI3 0.4 - 0.6 0.2 - 0.5 0.2 - 0.4 1.0 - 1.4

1990-94 CP 63 47 47 157Rate/NNS 0.55 0.41 0.41 1.3695% CI3 0.4 - 0.7 0.3 - 0.5 0.3 - 0.5 1.2 - 1.6

1995-99 CP 77 46 15 138Rate/NNS 0.67 0.40 0.13 1.1995% CI3 0.5 - 0.8 0.3 - 0.5 0.1 - 0.2 1.0 - 1.4



Table 13b: Non-spastic cerebral palsy1 birth prevalence rates per 1000 live births (LB) by cerebral palsy type and gestational age, Western Australia, 1980-1999 in 5-year groups

Non-spastic CP type2

GA group Grouped year of birth Ataxia Dyskinesia All non-spastic CP3

20-31w 1980-84 CP 1 0 1Rate/NNS 1.12 1.1295% CI4 0 - 3.3 0 - 3.3

1985-89 CP 0 2 2Rate/NNS 1.80 1.8095% CI4 0 - 4.3 0 - 4.3

1990-94 CP 2 0 2Rate/NNS 1.57 1.5795% CI4 0 - 3.7 0 - 3.7

1995-99 CP 3 2 5Rate/NNS 2.26 1.51 3.7795% CI4 0 - 4.8 0 - 3.6 0.5 - 7.1

32-36w 1980-84 CP 0 1 1Rate/NNS 0.15 0.1595% CI4 0 - 0.5 0 - 0.5

1985-89 CP 3 2 5Rate/NNS 0.38 0.26 0.6495% CI4 0 - 0.82 0 - 0.6 0.1 - 1.2

1990-94 CP 7 5 14Rate/NNS 0.82 0.58 1.6395% CI4 0.2 - 1.4 0.07 - 1.1 0.8 - 2.5

1995-99 CP 4 1 5Rate/NNS 0.46 0.11 0.5795% CI4 0.01 - 0.9 0 - 0.3 0.1 - 1.1

>=37w 1980-84 CP 15 20 36Rate/NNS 0.15 0.20 0.3595% CI4 0.1 - 0.2 0.2 - 0.3 0.2 - 0.5

1985-89 CP 22 20 47Rate/NNS 0.20 0.18 0.4295% CI4 0.1 - 0.3 0.1 - 0.3 0.3 - 0.5

1990-94 CP 19 28 51Rate/NNS 0.16 0.24 0.4495% CI4 0.1 - 0.2 0.2 - 0.3 0.3 - 0.6

1995-99 CP 20 35 59Rate/NNS 0.17 0.30 0.5195% CI4 0.1 - 0.3 0.2 - 0.4 0.4 - 0.6

1 Excludes cerebral palsy due to postneonatal causes2 Predominant cerebral palsy type; includes cases with lesser degree of spastic types3 Includes hypotonic cerebral palsy4 95% confi dence interval


Figures 12a-12d below show gestational-age specifi c cerebral palsy1 rates per 1000 neonatal survivors in hemiplegic, diplegic, quadriplegic and dyskinetic cerebral palsy, Western Australia, 1980-1999.

Figure 12a: Hemiplegia

0

5

10

15

20

25

30

35

1980-84 1985-89 1990-94 1995-99


Rate

per

1000 n

eo

nata

l

su

rviv

ors <=31w

32-36w

>=37w

Figure 12b: Diplegia

0

5

10

15

20

25

30

35

1980-84 1985-89 1990-94 1995-99


Rate

per

1000 n

eo

nata

l

su

rviv

ors <=31w

32-36w

>=37w

Figure 12c: Quadriplegia

0.0

1.0

2.0

3.0

4.0

5.0

6.0

7.0

8.0

9.0

1980-84 1985-89 1990-94 1995-99


Rate

per

1000 n

eo

nata

l

su

rviv

ors <=31w

32-36w

>=37w

Figure 12d: Dyskinetic CP

0.0

1.0

2.0

3.0

4.0

5.0

6.0

7.0

8.0

9.0

1980-84 1985-89 1990-94 1995-99


Rate

per

1000 n

eo

nata

l

su

rviv

ors <=31w

32-36w

>=37w


Please note: Range of vertical axis is 0-35/1000 neonatal survivors in Figures 12a and 12b and 0-8/1000 neonatal survivors in Figures 12c and 12d.


Table 14: Cerebral palsy1 birth prevalence rates per 1000 live births (LB) by cerebral palsy type and severity, Western Australia, 1975 - 1999 in 5-year groups

Cerebral palsy type2 & severity

Grouped year of birth1975 – 1979 1980 - 1984 1885 – 1989 1990 - 1994 1995-99

HemiplegiaMinimal/Mild CP 51 67 66 87 75

Rate/LB 0.50 0.61 0.54 0.69 0.5995% CI3 0.4 - 0.6 0.5 - 0.8 0.4 - 0.7 0.5 - 0.8 0.5 - 0.7% all CP 25.2 26.9 23.0 26.8 24.8

Moderate CP 26 30 22 26 31Rate/LB 0.25 0.27 0.18 0.21 0.2495% CI3 0.2 - 0.4 0.2 - 0.4 0.1 - 0.3 0.1 - 0.3 0.2 - 0.3% all CP 12.9 12.0 7.7 8.0 10.2

Severe CP 2 1 1 1 2Rate/LB 0.02 0.01 0.01 0.01 0.0295% CI3 0 – 0.05 0 – 0.03 0 - 0.02 0 - 0.02 0 - 0.04% all CP 1.0 0.4 0.3 0.3 0.7

DiplegiaMinimal/Mild CP 32 25 40 44 55

Rate/LB 0.31 0.23 0.33 0.35 0.4395% CI3 0.2 - 0.4 0.1 - 0.3 0.2 - 0.4 0.3 - 0.5 0.3 - 0.6% all CP 15.8 10.0 13.9 13.5 18.2

Moderate CP 26 31 34 29 37Rate/LB 0.25 0.28 0.28 0.23 0.2995% CI3 0.2 - 0.4 0.2 -0.4 0.2 - 0.4 0.2 - 0.3 0.2 - 0.4% all CP 12.9 12.4 11.8 8.9 12.2

Severe CP 14 14 19 21 10Rate/LB 0.14 0.13 0.16 0.17 0.0895% CI3 0.06 - 0.21 0.06 – 0.21 0.09 - 0.23 0.1 - 0.2 0.03 - 0.13% all CP 6.9 5.6 6.6 6.5 3.3

QuadriplegiaMinimal/Mild CP 6 0 1 2 0

Rate/LB 0.06 0.00 0.01 0.0295% CI3 0.01 – 0.1 0.01 - 0.02 0 - 0.04% all CP 3.0 0.3 0.6

Moderate CP 4 8 10 3 1Rate/LB 0.04 0.07 0.08 0.02 0.0195% CI3 0 - 0.08 0.02 - 0.12 0.03 - 0.13 0 - 0.05 0 - 0.02% all CP 2.0 3.2 3.5 0.9 0.3

Severe CP 14 35 39 46 23Rate/LB 0.14 0.32 0.32 0.36 0.1895% CI3 0.06 - 0.21 0.2 - 0.5 0.2 - 0.4 0.3 - 0.5 0.1 - 0.3% all CP 6.9 14.1 13.6 14.2 7.6

All spastic CPMinimal/Mild CP 89 102 107 133 143

Rate/LB 0.86 0.92 0.88 1.05 1.1395% CI3 0.7 - 1.0 0.7 - 1.1 0.7 - 1.1 0.9 - 1.2 0.9 - 1.3% all CP 44.1 41.0 37.3 40.9 47.2


Severe CP 30 50 59 68 35Rate/LB 0.29 0.45 0.49 0.54 0.2895% CI3 0.2 - 0.4 0.3 - 0.6 0.4 - 0.6 0.4 - 0.7 0.2 - 0.4

% all CP 14.9 20.1 20.6 20.9 11.6


Table 14 (continued)

Cerebral palsy type2 & severity


1975 – 1979 1980 - 1984 1885 – 1989 1990 - 1994 1995-99

AtaxiaMinimal/Mild CP 10 10 20 16 13

Rate/LB 0.10 0.09 0.16 0.13 0.1095% CI3 0.04 - 0.16 0.03 - 0.15 0.09 -0.24 0.06 - 0.19 0.05 - 0.16% all CP 5.0 4.0 7.0 4.9 4.3

Moderate CP 3 4 5 10 12Rate/LB 0.03 0.04 0.04 0.08 0.0995% CI3 0 - 0.06 0 - 0.07 0.01 - 0.08 0.03 - 0.13 0.04 - 0.15% all CP 1.5 1.6 1.7 3.1 4.0

Severe CP 0 2 0 2 2Rate/LB 0.02 0.02 0.0295% CI3 0 - 0.04 0 - 0.04 0 - 0.04% all CP 0.0 0.8 0.0 0.6 0.7

DyskinesiaMinimal/Mild CP 4 4 6 1 3

Rate/LB 0.04 0.04 0.05 0.01 0.0295% CI3 0 - 0.08 0 - 0.07 0.01 - 0.09 0 - 0.02 0 - 0.05% all CP 2.0 1.6 2.1 0.3 1.0

Moderate CP 3 4 5 10 5Rate/LB 0.03 0.04 0.04 0.08 0.0495% CI3 0.0 - 0.06 0.0 - 0.07 0.01 - 0.08 0.03 - 0.13 0 - 0.07% all CP 1.5 1.6 1.7 3.1 1.7

Severe CP 6 13 13 22 30Rate/LB 0.06 0.12 0.11 0.17 0.2495% CI3 0.01 - 0.1 0.05 - 0.18 0.05 - 0.17 0.1 - 0.25 0.15 -0.32% all CP 3.0 5.2 4.5 6.8 9.9

All non-spasticCP4

Minimal/Mild CP 14 14 29 18 16Rate/LB 0.14 0.13 0.24 0.14 0.1395% CI3 0.06 - 0.21 0.06 - 0.19 0.15 - 0.3 0.08 - 0.21 0.06 - 0.19% all CP 6.9 5.6 10.1 5.5 5.3


Severe CP 6 16 14 28 36Rate/LB 0.06 0.14 0.12 0.22 0.2895% CI3 0.01 - 0.10 0.07 - 0.22 0.05 - 0.18 0.14 - 0.30 0.19 - 0.38% all CP 3.0 6.4 4.9 8.6 11.9

1 Excludes cerebral palsy due to postneonatal causes2 Predominant cerebral palsy type; includes cases with lesser degree of other spastic or non-spastic types3 95% confi dence interval4 Includes hypotonic cerebral palsy


ASSOCIATED DISABILITIES:

(1) INTELLECTUAL DISABILITY

Cerebral palsy rates by IQ range are shown in 5-year groups in Table 15 below and in 10-year groups in Figure 13 on the following page. These data are derived from a number of different methods of measuring IQ/DQ (developmental quotient) and are therefore presented in broad categories. As intellectual ability is assessed at age 6 in some educational and service organisations, this information may be unavailable at the time of the 5-year-old update of information for the Register.

Rates of cerebral palsy with associated intellectual disability by severity of cerebral palsy are shown in the subsequent Table 16a, and by predominant type of cerebral palsy in Table 16b and Figures 14a and 14b.

Table 15: Cerebral palsy1 birth prevalence rates per 1000 live births (LB) by IQ range2, Western Australia, 1960 - 1999

IQ range2

Normal IQ/ Mild/ Severe/ IQ AllGrouped year of birth Borderline

IDModerate

ID3Profound ID Unknown IQ <70

1960-64 CP 77 67 53 5 120Rate/LB 0.91 0.79 0.62 1.4195% CI4 0.7 - 1.1 0.6 - 1.0 0.5 - 0.8 1.2 - 1.7% all CP 38.1 33.2 26.2 2.5 59.4








1 Excludes cerebral palsy due to postneonatal causes2 Normal = IQ >=85, borderline ID (intellectual disability) = 70-84, mild ID = 50-69, moderate ID = 35-49, severe ID = 20-34, profound

ID = <203 Includes intellectual disability not further specifi ed4 95% confi dence interval


Figure 13: Cerebral palsy1 rates per 1000 live births by IQ range2, Western Australia, 1960-1999

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1.6R

ate

per

1000 liv

e b

irth

s

1960-69

1970-79

1980-89

1990-99

1 Excludes cerebral palsy due to postneonatal causes2 Normal/borderline ID (intellectual disability) = IQ>=70; mild/moderate ID = IQ 35-69; severe/profound ID = IQ<353 Includes intellectual disability not further specif ied

Normal IQ/

Borderline ID

Mild/

Moderate ID3

Severe/

Profound ID

All

IQ <70

Table 16a: Birth prevalence rates per 1000 live births (LB) for cerebral palsy associated with intellectual disability (IQ <70) by severity of cerebral palsy, Western Australia, 1975 - 1999 in 5-year groups


Grouped year of birth Minimal/Mild Moderate Severe

1975-79 CP + ID 28 17 24Rate/LB 0.27 0.17 0.2395% CI4 0.17 - 0.37 0.09 - 0.24 0.14 - 0.33% all CP 13.8 8.4 11.8







Table 16b: Birth prevalence rates per 1000 live births (LB) for cerebral palsy1 associated with intellectual disability (IQ <70) by cerebral palsy type2, Western Australia, 1975 - 1999 in 5-year groups


Cerebral Palsy Type2 1975–1979 1980-1984 1885–1989 1990–1994 1995-1999

Hemiplegia CP + ID 16 23 15 10 12Rate/LB 0.16 0.21 0.12 0.08 0.0995% CI3 0.08 - 0.23 0.12 - 0.29 0.06 - 0.19 0.03 - 0.13 0.04 - 0.15% all CP4 7.9 9.2 5.2 3.1 4.0

Diplegia CP + ID 20 24 24 29 29Rate/LB 0.19 0.22 0.20 0.23 0.2395% CI3 0.11 - 0.28 0.13 - 0.30 0.12 - 0.28 0.15 - 0.31 0.15 - 0.31% all CP4 9.9 9.6 8.4 8.9 9.6

Quadriplegia CP + ID 22 37 46 44 23Rate/LB 0.21 0.33 0.38 0.35 0.1895% CI3 0.12 - 0.30 0.23 - 0.44 0.27 - 0.49 0.25 - 0.45 0.11 - 0.25% all CP4 10.8 14.8 16.0 13.5 7.6

All spastic CP CP + ID 58 84 85 83 64Rate/LB 0.56 0.76 0.70 0.66 0.5095% CI3 0.42 - 0.71 0.60 - 0.92 0.55 - 0.85 0.52 - 0.80 0.38 - 0.63% all CP4 28.6 33.6 29.6 25.5 21.1

Ataxia CP + ID 5 6 13 14 14Rate/LB 0.05 0.05 0.11 0.11 0.1195% CI3 0.01 – 0.09 0.01 - 0.10 0.05 - 0.17 0.05 - 0.17 0.05 - 0.17% all CP4 2.5 2.4 4.5 4.3 4.6

Dyskinesia CP + ID 5 16 18 25 30Rate/LB 0.05 0.14 0.15 0.20 0.2495% CI3 0.01 - 0.09 0.07 - 0.22 0.08 - 0.22 0.12 - 0.28 0.15 - 0.32% all CP4 2.5 6.4 6.3 7.7 9.9

All non-spastic CP5 CP + ID 11 23 35 43 48Rate/LB 0.11 0.21 0.29 0.34 0.3895% CI3 0.04 - 0.17 0.12 - 0.29 0.19 - 0.38 0.24 - 0.44 0.27 - 0.48% all CP4 5.4 9.2 12.2 13.2 15.8

1 Excludes cerebral palsy due to postneonatal causes2 Predominant cerebral palsy type; includes cases with lesser degree of other spastic and/or non-spastic types3 95% confi dence interval4 Percentage of all cerebral palsy in the same year group5 Includes hypotonic cerebral palsy


Figure 14a: Rates of spastic cerebral palsy1associated with intellectual disability (IQ <70), Western Australia, 1975-1999

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8


Ra

te p

er

10

00

liv

e b

irth

s

1975-1979

1980-1984

1985-1989

1990-1994

1995-1999


Figure 14b: Rates of non-spastic cerebral palsy1associated with intellectual disability (IQ <70), Western Australia, 1975-1999

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8


Ra

te p

er

10

00

liv

e b

irth

s

1975-1979

1980-1984

1985-1989

1990-1994

1995-1999



ASSOCIATED DISABILITIES

(2) EPILEPSY, BLINDNESS, DEAFNESS AND LACK OF SPEECH

During the period 1975-99 the proportion of all cerebral palsy cases that also had epilepsy was 31%, those with blindness 7%, deafness 2% and lack of speech approximately 21%. In those with an intellectual disability (IQ <70), these proportions rise to 59%, 17%, 5% and 48% respectively (data not shown).

Rates of cerebral palsy with these associated disabilities are shown in 5-year groups in Table 17 and in 10-year groups in Figure 15.

Table 17: Cerebral palsy1 rates per 1000 live births associated with epilepsy, blindness, deafness and lack of speech, Western Australia, 1960-1999 in 10-year groups

Other disability

Grouped year of birth Epilepsy Blind Deaf Non-verbal2

1960-64 CP 92 28 14 N/ARate/LB 1.08 0.33 0.1695% CI3 0.86 – 1.30 0.21 – 0.45 0.08 - 0.25% all CP 45.5 13.9 6.9

1965-69 CP 80 13 10 N/ARate/LB 0.87 0.14 0.1195% CI3 0.68 – 1.07 0.06 – 0.22 0.04 – 0.18% all CP 37.9 6.2 4.7

1970-74 CP 78 15 9 N/ARate/LB 0.72 0.14 0.0895% CI3 0.56 – 0.88 0.07 – 0.21 0.03 – 0.14% all CP 39.0 7.5 4.5

1975-79 CP 63 9 0 19Rate/LB 0.61 0.09 0.1895% CI3 0.46 – 0.76 0.03 – 0.14 0.10 – 0.27% all CP 31.0 4.4 9.4

1980-84 CP 90 25 6 55Rate/LB 0.81 0.23 0.05 0.5095% CI3 0.65 - 0.98 0.14 – 0.31 0.01 - 0.10 0.37 - 0.63% all CP 36.0 10.0 2.4 22.0



1995-99 CP 98 13 5 71Rate/LB 0.77 0.10 0.04 0.5695% CI3 0.62 - 0.92 0.05 - 0.16 0 - 0.07 0.43 - 0.69% all CP 32.3 4.3 1.7 23.4

1 Excludes cerebral palsy due to postneonatal causes2 Speech data not available before 19753 95% confi dence interval


Figure 15: Rates of cerebral palsy1 associated with epilepsy, blindness, deafness or lack of speech, Western Australia, 1960-19992

0.0

0.2

0.4

0.6

0.8

1.0

Epilepsy Blind Deaf

Rat

e pe

r 100

0 liv

e bi

rths

1960-691970-791980-891990-99

Non-verbal

1 Excludes cerebral palsy due to postneonatal causes2 Data re speech not available 1960-79

Not

Ava

ilabl

e

Not

Ava

ilabl

e

AGE AT RECOGNITION OF CEREBRAL PALSY

Figure 16 and Table 18 below show the proportions of cerebral palsy by year of fi rst recognition from 1960 to 1999 in 10-year groups. Cerebral palsy was more often identifi ed during the fi rst year than in any subsequent year in all periods. The increased proportion of cases born 1990-99 recognised in the fi fth year or later may represent the growing number of very mild cases presenting at older ages with a view to accessing botulinum A toxin therapy.

Figure 16: Proportion of cerebral palsy1recognised during each successive year of life, Western Australia, 1960-1999

0% 20% 40% 60% 80% 100%

1990-99

1980-89

1970-79

1960-69

Percent of all cerebral palsy

1st year

2nd year

3rd year

4th year

5th year or later

Not recorded



Table 18: Proportion of cerebral palsy1 recognised during each successive year of life by severity of cerebral palsy, Western Australia, 1960 - 1999 in 10-year groups

Year of life during which CP fi rst recognised


Min/Mild Moderate Severe Unknown All severities

1960-691st year CP 69 39 49 30 187

% all CP2 35.2 39.4 77.8 54.5 45.32nd year CP 42 26 6 8 82

% all CP2 21.4 26.3 9.5 14.5 19.93rd year CP 25 17 2 3 47

% all CP2 12.8 17.2 3.2 5.5 11.44th year CP 17 5 0 6 28

% all CP2 8.7 5.1 0.0 10.9 6.85th or later CP 22 3 1 2 28

% all CP2 11.2 3.0 1.6 3.6 6.8Not recorded CP 21 9 5 6 41

% all CP2 10.7 9.1 7.9 10.9 9.9

1970-791st year CP 68 66 53 11 198

% all CP2 37.4 48.9 84.1 47.8 49.12nd year CP 42 32 4 6 84

% all CP2 23.1 23.7 6.3 26.1 20.83rd year CP 19 10 2 2 33

% all CP2 10.4 7.4 3.2 8.7 8.24th year CP 5 0 0 0 5

% all CP2 2.7 1.25th or later CP 12 3 0 0 15

% all CP2 6.6 2.2 3.7Not recorded CP 36 24 4 4 68

% all CP2 19.8 17.8 6.3 17.4 16.9

1980-891st year CP 96 87 118 0 301

% all CP2 39.7 56.1 84.9 56.12nd year CP 57 28 14 0 99

% all CP2 23.6 18.1 10.1 18.43rd year CP 11 9 1 0 21

% all CP2 4.5 5.8 0.7 3.94th year CP 7 4 0 0 11

% all CP2 2.9 2.6 2.05th or later CP 18 1 0 0 19


% all CP2 21.9 16.8 4.3 100.0 16.0

1990-991st year CP 85 100 142 0 327

% all CP2 28.6 61.0 85.0 52.02nd year CP 81 31 11 1 124

% all CP2 27.3 18.9 6.6 100.0 19.73rd year CP 36 11 4 0 51

% all CP2 12.1 6.7 2.4 8.14th year CP 25 1 0 0 26

% all CP2 8.4 0.6 4.15th or later CP 35 4 0 0 39


% all CP2 11.8 10.4 6.0 9.9

1 Excludes cerebral palsy due to postneonatal causes2 Percentage of all cerebral palsy in the same severity category

SECTION II:

POSTNEONATALLY ACQUIRED CEREBRAL PALSY


The WA Cerebral Palsy Register includes cerebral palsy due to postneonatal causes that occur up to the age of 5 years. Data for this group are reported below.

TRENDS IN POSTNEONATALLY ACQUIRED CEREBRAL PALSY

Rates of postneonatally acquired cerebral palsy have risen (Figure 17) despite the fact that since the cause is known, this group should be the most amenable to preventive strategies. As shown in Table 19 below, the proportion of all cerebral palsy in WA acquired postneonatally rose steeply from 10% in 1960-74 to 22% in 1975-79. While there may be some under-ascertainment in the early years, the proportion since 1975 has remained higher than what has been recently reported by some other registers22-24.

Figure 17: Postneonatal cerebral palsy rates per 1000 live births, Western Australia, 1960-1999

0.00

0.05

0.10

0.15

0.20

0.25

0.30

0.35

0.40

0.45

1960-64 1965-69 1970-74 1975-79 1980-84 1985-89 1990-94 1995-99


Rate

per

1000 liv

e b

irth

s

Table 19: Postneonatally acquired cerebral palsy (PNN CP) birth prevalence rates per 1000 live births (LB), Western Australia, 1960 - 1999 in 5-year groups

Grouped year of birth PNN CP Rate/LB Rate/NNS 95% CI1 % all CP

1960-64 20 0.24 0.24 0.13 - 0.34 9.9

1965-69 20 0.22 0.22 0.12 - 0.32 9.5

1970-74 26 0.24 0.24 0.15 - 0.34 13.0

1975-79 44 0.43 0.43 0.30 - 0.56 21.7

1980-84 46 0.42 0.42 0.30 - 0.54 18.4

1985-89 49 0.40 0.41 0.29 - 0.52 17.1

1990-94 42 0.33 0.33 0.23 - 0.43 12.9

1995-99 49 0.39 0.39 0.28 - 0.50 16.2

1 95% confi dence interval


GENDER

Figure 18: Postneonatal cerebral palsy rates by gender, Western Australia, 1960-1999

0.0

0.1

0.2

0.3

0.4

0.5

1960-69 1970-79 1980-89 1990-99


Rat

e pe

r 100

0 liv

e bi

rths Males

Females

Table 20: Postneonatally acquired cerebral palsy (PNN CP) birth prevalence rates per 1000 live births (LB) by gender, Western Australia, 1960 - 1999 in 10-year groups

Gender

Grouped year of birth Male (M/F ratio) Female

1960-69 PNN CP 22 1.2 18Rate/LB 0.24 0.2195% CI1 0.14 – 0.34 0.11 – 0.31% all PNN CP 55.0 45.0

1970-79 PNN CP 38 1.2 32Rate/LB 0.35 0.3195% CI1 0.24 – 0.46 0.20 – 0.42% all PNN CP 54.3 45.7

1980-89 PNN CP 53 1.3 42Rate/LB 0.44 0.3795% CI1 0.32 - 0.56 0.26 – 0.49% all PNN CP 55.8 44.2

1990-99 PNN CP 58 1.8 33Rate/LB 0.45 0.2795% CI1 033 - 0.56 0.18 - 0.36% all PNN CP 63.7 36.3



AREA OF RESIDENCE

Figure 19: Postneonatal cerebral palsy rates by area of residence, Western Australia, 1960-1999

0.0

0.1

0.2

0.3

0.4

0.5

0.6

1960-69 1970-79 1980-89 1990-99


Rate

per

1000 liv

e b

irth

s

Metro

Rural

Table 21: Postneonatally acquired cerebral palsy (PNN CP) birth prevalence rates per 1000 live births (LB) by metropolitan or rural residence at time of birth, Western Australia, 1960 - 1999 in 10-year groups

Area of residenceGrouped year of birth Metropolitan Rural

1960-69 PNN CP 25 15Rate/LB 0.23 0.2195% CI1 0.14 – 0.33 0.11 – 0.32% all PNN CP 62.5 37.5



1990-99 PNN CP 55 36Rate/LB 0.31 0.4695% CI1 0.23 - 0.40 0.31 - 0.61% all PNN CP 60.4 39.6



INDIGENOUS STATUS OF MOTHER

Population data on indigenous status are available only from 1980 onwards.

Figure 20: Postneonatal cerebral palsy rates per 1000 live births by Indigenous status of mother, Western Australia, 1980-1999

0.0

0.5

1.0

1.5

2.0

2.5

1980-84 1985-89 1990-94 1995-99


Rate

per

1000 liv

e b

irth

s

Indigenous

Non-Indigenous

Table 22: Postneonatally acquired cerebral palsy (PNN CP) birth prevalence rates per 1000 live births (LB) by indigenous status of mother, Western Australia, 1980 – 1999 in 5-year groups

Indigenous status of motherGrouped year of birth Non-Indigenous Indigenous

1980-84 PNN CP 33 13Rate/LB 0.31 2.3495% CI1 0.21 - 0.42 1.07 – 3.61% all PNN CP 71.7 28.3

1985-89 PNN CP 36 13Rate/LB 0.31 1.9695% CI1 0.21 - 0.42 0.90 – 3.02% all PNN CP 73.5 26.5

1990-94 PNN CP 29 13Rate/LB 0.24 1.7895% CI1 0.16 - 0.33 0.81 -2.75% all PNN CP 69.0 31.0

1995-99 PNN CP 35 14Rate/LB 0.29 1.8695% CI1 0.20 - 0.39 0.88 - 2.83% all PNN CP 71.4 28.6



AGE OF MOTHER

The increase in postneonatally acquired cerebral palsy has occurred particularly in the youngest mothers, with the high rates for mothers aged 35 years or more coming down in the most recent 10-year period.

Figure 21: Postneonatal cerebral palsy rates per 1000 live births by age of mother, Western Australia, 1960-1999

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

<20 20-24 25-29 30-34 >=35

Age of mother (years)

Rate

per

1000 liv

e b

irth

s

1960-69

1970-79

1980-89

1990-99

Table 23: Postneonatally acquired cerebral palsy (PNN CP) birth prevalence rates per 1000 live births (LB) by age of mother at time of birth, Western Australia, 1960 – 1999 in 10-year groups

Age of mother (years)Grouped year of birth <20 20-24 25-29 30-34 >=35

1960-69 PNN CP 3 14 14 3 3Rate/LB 0.16 0.23 0.27 0.11 0.1795% CI1 0 – 0.34 0.11 – 0.35 0.13 – 0.41 01 – 0.23 0 – 0.37% all PNN CP 7.5 35.0 35.0 7.5 7.5

1970-79 PNN CP 10 24 22 6 8Rate/LB 0.43 0.32 0.30 0.20 0.7395% CI1 0.16 – 0.70 0.19 – 0.45 0.18 – 0.43 0.04 – 0.36 0.23 – 1.23% all PNN CP 14.3 34.3 31.4 8.6 11.4

1980-89 PNN CP 14 28 24 17 10Rate/LB 0.88 0.45 0.27 0.34 0.6595% CI1 0.42 – 1.34 0.29 – 0.62 0.16 – 0.38 0.18 – 0.51 0.25 – 1.05% all PNN CP 14.7 29.5 25.3 17.9 10.5

1990-99 PNN CP 13 31 28 13 6Rate/LB 0.84 0.64 0.33 0.18 0.1995% CI1 0.38 - 1.30 0.41 - 0.86 0.21 - 0.45 0.08 - 0.28 0.04 - 0.34% all PNN CP 14.3 34.1 30.8 14.3 6.6



SEVERITY OF CEREBRAL PALSY

Compared with pre- and perinatally acquired cerebral palsy, postneonatal cerebral palsy has a higher proportion of severe cases (30% cf 25%) (Figures 22 and 10a). Rates have tended to increase over time in all categories of severity as shown in Table 24 and Figure 23.

Figure 22: Postneonatally acquired cerebral palsy proportions by severity, 1975-1999 combined

Minimal CP

15%

Mild CP

30%Moderate CP

25%

Severe CP

30%

Table 24: Postneonatally acquired cerebral palsy (PNN CP) birth prevalence rates per 1000 live births (LB) by severity of cerebral palsy, Western Australia, 1960 - 1989 in 10-year groups


Grouped year of birth Minimal/Mild Moderate Severe1960-69 CP 17 10 10

Rate/LB 0.10 0.06 0.0695% CI1 0.05 – 0.14 0.02 – 0.09 0.02 – 0.09% all PNN CP 42.5 25.0 25.0

1970-79 CP 28 22 19Rate/LB 0.13 0.10 0.0995% CI1 0.08 – 0.18 0.06 – 0.15 0.05 – 0.13% all PNN CP 40.0 31.4 27.1

1980-89 CP 43 26 26Rate/LB 0.19 0.11 0.1195% CI1 0.13 – 0.24 0.07 – 0.16 0.07 – 0.16% all PNN CP 45.3 27.4 27.4

1990-99 CP 40 19 31Rate/LB 0.16 0.07 0.1295% CI1 0.11 - 0.21 0.04 - 0.11 0.08 - 0.17% all PNN CP 44.0 20.9 34.1



Figure 23: Postneonatal cerebral palsy rates per 1000 live births by motor severity, Western Australia, 1960-1999

0.00

0.02

0.04

0.06

0.08

0.10

0.12

0.14

0.16

0.18

0.20



Rate

per

1000 liv

e b

irth

s

1960-69

1970-79

1980-89

1990-99


TYPE OF CEREBRAL PALSY

Compared with pre- and perinatally acquired cerebral palsy, a very different distribution of cerebral palsy type is seen in postneonatally acquired cases with hemiplegia (55% cf 36%) and quadriplegia (24% cf 14%) dominating (Figures 24 and 11a).

Figure 24: Postneonatally acquired cerebral palsy proportions by predominant type, 1975-1999 combined

Spastic hemiplegia

55%

Spastic diplegia

10%

Spastic quadriplegia

24%

Ataxic CP

5.5%

Dyskinetic CP

5.5%

Table 25: Postneonatally acquired cerebral palsy (PNN CP) birth prevalence rates per 1000 live births (LB) by cerebral palsy type, Western Australia, 1960 - 1989 in 10-year groups

Grouped year of birthCerebral Palsy Type 1970-79 1980-89 1990-99

Hemiplegia PNN CP 34 54 52Rate/LB 0.16 0.23 0.2195% CI1 0.11 – 0.21 0.17– 0.29 0.15 - 0.27% all PNN CP 48.6 56.8 57.1

Diplegia PNN CP 12 5 9Rate/LB 0.06 0.02 0.0495% CI1 0.02 – 0.09 0 – 0.04 0.01 - 0.06% all PNN CP 17.1 5.3 9.9

Quadriplegia PNN CP 17 24 20Rate/LB 0.08 0.10 0.0895% CI1 0.04 – 0.12 0.06 – 0.14 0.05 - 0.12% all PNN CP 24.3 25.3 22.0

All spastic CP PNN CP 63 83 81Rate/LB 0.30 0.36 0.3395% CI1 0.22 – 0.37 0.28 – 0.43 026 - 0.40% all PNN CP 90.0 87.4 89.0

Ataxia PNN CP 2 5 6Rate/LB 0.01 0.02 0.0295% CI1 0 – 0.02 0 – 0.04 0 - 0.04% all PNN CP 2.9 5.3 6.6

Dyskinesia PNN CP 5 7 4Rate/LB 0.02 0.03 0.0295% CI1 0 – 0.04 0.01 – 0.05 0 - 0.03% all PNN CP 7.1 7.4 4.4

All non-spastic CP PNN CP 7 12 10Rate/LB 0.03 0.05 0.0495% CI1 0.01 – 0.06 0.02 – 0.08 0.02 - 0.06% all PNN CP 10.0 12.6 11.0



Figure 25a: Postneonatal spastic cerebral palsy rates per 1000 live births by spastic type, Western Australia, 1970-1999

0.00

0.05

0.10

0.15

0.20

0.25

0.30

0.35

0.40


Type of spastic cerebral palsy

Rate

per

1000 liv

e b

irth

s

1970-79

1980-89

1990-99

Figure 25b: Postneonatal non-spastic cerebral palsy rates per 1000 live births by type of cerebral palsy, Western Australia, 1970-1999

0.00

0.05

0.10

0.15

0.20

0.25

0.30

0.35

0.40


Cerebral palsy type

Rate

per

1000 liv

e b

irth

s

1970-79

1980-89

1990-99



(1) INTELLECTUAL DISABILITY

Figure 26: Postneonatal cerebral palsy rates per 1000 live births by IQ range1, Western Australia, 1960-1999

0.00

0.05

0.10

0.15

0.20

0.25

Rate

per

1000 liv

e b

irth

s

1960-69

1970-79

1980-89

1990-99

1 Normal IQ/borderline ID (intellectual disability) = IQ>=70; mild/moderate ID = IQ 35-69; severe/profound ID = IQ<352 Includes intellectual disability not further specif ied

Normal IQ/

Borderline ID

Mild/Moderate

ID2

Severe/

Profound IDAll

IQ <70

Table 26: Postneonatally acquired cerebral palsy (PNN CP) birth prevalence rates per 1000 live births (LB) by IQ range1, Western Australia, 1960 - 1999 in 10-year groups

IQ range1

Normal IQ/ Borderline

ID

Mild/ Moderate

ID2

Severe/ Profound

ID

IQUnknown All IQ <70Grouped year of birth

1960-69 PNN CP 12 13 14 1 27Rate/LB 0.07 0.07 0.08 0.1595% CI3 0.03 – 0.11 0.03 – 0.11 0.04 – 0.12 0.10 – 0.21% all PNN CP 30.0 32.5 35.0 2.5 67.5



1990-99 PNN CP 40 29 14 8 43Rate/LB 0.16 0.11 0.06 0.1795% CI3 0.11 - 0.21 0.07 - 0.16 0.03 - 0.08 0.12 - 0.22% all PNN CP 44.0 31.9 15.4 8.8 47.3

1 Normal = IQ>85, borderline ID (intellectual disability) = 70-84, mild = 50-69, moderate = 35-49, severe = 20-34, profound = <202 Includes intellectual disability not further specifi ed3 95% confi dence interval



(2) EPILEPSY, BLINDNESS, DEAFNESS AND LACK OF SPEECH

Figure 27: Postneonatal cerebral palsy rates per 1000 live births by presence of associated conditions,Western Australia, 1960-1999

0.00

0.05

0.10

0.15

0.20

0.25

Epilepsy Blind Deaf Non-verbal

Associated conditions

Rate

per

1000 liv

e b

irth

s

1960-69

1970-79

1980-89

1990-99

Not

ava

ilabl

e

Not

ava

ilabl

e

Table 27: Postneonatal cerebral palsy rates per 1000 live births by presence of associated conditions, Western Australia, 1960-1999

Other disabilityGrouped year of birth Epilepsy Blind Deaf Non-verbal

1960-69 PNN CP 17 4 1 N/ARate/LB 0.10 0.02 0.0195% CI1 0.05 – 0.14 0 – 0.04 -0.01 – 0.02% all PNN CP 42.5 10.0 2.5

1970-79 PNN CP 31 10 3 N/ARate/LB 0.15 0.05 0.0195% CI1 0.09 – 0.20 0.02 – 0.08 0 – 0.03% all PNN CP 44.3 14.3 4.3

1980-89 PNN CP 46 16 1 21Rate/LB 0.20 0.07 0.00 0.0995% CI1 0.14 – 0.26 0.04 – 0.10 0 – 0.01 0.05 - 0.13% all PNN CP 48.4 16.8 1.1 22.1

1990-99 PNN CP 33 8 2 20Rate/LB 0.13 0.03 0.01 0.0895% CI1 0.09 - 0.17 0.01 - 0.05 0 - 0.02 0.04 - 0.11% all PNN CP 36.3 8.8 2.2 22.0



POSTNEONATAL CAUSES OF CEREBRAL PALSY

Figure 28: Postneonatal cerebral palsy rates per 1000 live births by cause, Western Australia, 1970-1999

0.00

0.02

0.04

0.06

0.08

0.10

0.12

0.14

Infection Head Injury CVA Other

Postneonatal cause of cerebral palsy

Rate

per

1000 liv

e b

irth

s

1970-79

1980-89

1990-99

Table 28: Postneonatally acquired cerebral palsy (PNN CP) birth prevalence rates per 1000 live births (LB) by cause, Western Australia, 1970 - 1989 in 5-year groups

Cause of postneonatal cerebral palsyGrouped year of birth Infection Head Injury CVA Other

1970-79 PNN CP 24 27 11 8Rate/LB 0.11 0.13 0.05 0.0495% CI1 0.07 - 0.16 0.08 - 0.18 0.02 - 0.08 0.01 - 0.06% all PNN CP 34.3 38.6 15.7 11.4

1980-89 PNN CP 29 31 21 14Rate/LB 0.13 0.13 0.09 0.0695% CI1 0.08 - 0.17 0.09 - 0.18 0.05 - 0.13 0.03 - 0.09% all PNN CP 30.5 32.6 22.1 14.7

1990-99 PNN CP 25 32 18 15Rate/LB 0.10 0.13 0.07 0.0695% CI1 0.06 - 0.14 0.08- 0.17 0.04 - 0.10 0.03 - 0.09% all PNN CP 27.5 35.2 19.8 16.5



POSTNEONATAL CAUSES BY INDIGENOUS STATUS

Infection is the most important cause of postneonatally acquired cerebral palsy in Indigenous children; however this has declined in response to Haemophilus infl uenza B and pneumococcal vaccination programs introduced in the 1980s and 1990s. The most important postneonatal cause of cerebral palsy in non-Indigenous cases is head injury, and there is no evidence that this is changing.

Figure 29: Postneonatal cerebral palsy (PNN CP) by cause and Indigenous status of mother as a percentage of all PNN CP in that Indigenous status group, Western Australia, 1970-1999

0

10

20

30

40

50

60

70

Infe

cti

on

Head

inju

ry

CV

A

Oth

er

Infe

cti

on

Head

inju

ry

CV

A

Oth

er

Perc

en

t o

f all P

NN

CP

of

that

race

1970-79

1980-89

1990-99

Non-Indigenous Indigenous

Table 29: Proportion of postneonatally acquired cerebral palsy (PNN CP) caused by infection, head injury, cerebrovascular accident or other cause in children of non-Indigenous and Indigenous mothers, Western Australia, 1970 - 1999 in 10-year groups

Indigenous status of motherNon-Indigenous Indigenous

Grouped year of birth No. % all PNN CP1 No. % all PNN CP1

1970-79 Infection 10 20.8 14 66.7Head injury 22 45.8 4 19.0CVA 8 16.7 3 14.3Other 8 16.7 0 0.0



1 % of all postneonatal cerebral palsy in the same race group


POSTNEONATAL YEAR OF ACQUISITION OF CEREBRAL PALSY

Figure 30: Proportion of cerebral palsy acquired postneonatally by year of acquisition, Western Australia, 1960-1999

0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%

1990-99

1980-89

1970-79

1960-69G

rou

ped

year

of

bir

th

Percent of all cerebral palsy

1st year

2nd year

3rd year

4th year

5th year

Table 30: Proportion of cerebral palsy acquired postneonatally (PNN CP) by year of life of acquisition, Western Australia, 1960 – 1999 in 10-year groups

Year of life during which cerebral palsy acquiredGrouped year of birth 1st year 2nd year 3rd year 4th year 5th year

1960-69 PNN CP* 18 7 4 5 5All PNN CP 40% all PNN CP 45.0 17.5 10.0 12.5 12.5

1970-79 PNN CP* 33 9 10 10 7All PNN CP 70% all PNN CP 47.1 12.9 14.3 14.3 10.0

1980-89 PNN CP 45 24 15 8 3All PNN CP 95% all PNN CP 47.4 25.3 15.8 8.4 3.2

1990-99 PNN CP 45 23 13 6 3All PNN CP 91% all PNN CP 49.5 25.3 14.3 6.6 3.3

* 1 case has unknown age at acquisition


REFERENCES

1 Stanley FJ. An epidemiological study of cerebral palsy in Western Australia, 1956-1975. I: Changes in total incidence of cerebral palsy and associated factors. Developmental Medicine and Child Neurology 1979; 21: 701-713.

2 Dale A, Stanley FJ. An epidemiological study of cerebral palsy in Western Australia, 1956-1975. II: Spastic cerebral palsy and perinatal factors. Developmental Medicine and Child Neurology 1980; 22: 13-25.

3 Blair E, Stanley FJ. An epidemiological study of cerebral palsy in Western Australia, 1956-1975. III: Cerebral palsy of postnatal aetiology. Developmental Medicine and Child Neurology 1982; 24: 575-585.

4 Blair E, Watson L, Badawi N, Stanley FJ. Life expectancy among people with cerebral palsy in Western Australia. Developmental Medicine and Child Neurology 2001; 43: 508-515.

5 Surveillance of Cerebral Palsy in Europe (SCPE). Surveillance of cerebral palsy in Europe: a collaboration of cerebral palsy surveys and registers. Developmental Medicine and Child Neurology 2000; 42: 816-824.

6 Blair E, Love S. Commentary: Defi nition and classifi cation of cerebral palsy. Developmental Medicine and Child Neurology 2005; 47: 510.

7 Bax M, Goldstein M, Rosenbaum P, Leviton A, Paneth N. Proposed defi nition and classifi cation of cerebral palsy, April 2005. Developmental Medicine and Child Neurology 2005; 47: 571-576.

8 The Australian Cerebral Palsy Register. Proposed new defi nition of cerebral palsy does not solve any of the problems of existing defi nitions. Developmental Medicine and Child Neurology 2006; 48: 78.

9 Blair E, Stanley FJ. Issues in the classifi cation and epidemiology of cerebral palsy. Mental Retardation and Developmental Disabilities Research Reviews 1997; 3: 184-193.

10 Badawi N, Watson L, Petterson B, Blair E, Slee J, Haan E, Stanley F. What constitutes cerebral palsy? Developmental Medicine and Child Neurology 1998; 40; 520-527.

11 Stanley FJ, Croft ML, Gibbins J, Read AW. A population database for maternal and child health research in Western Australia using record linkage. Paediatric and Perinatal Epidemiology 1994; 8: 433-447.

12 Sayer FW. Statistics of Western Australia. Demography 1968. Perth: Government Printer, 1971.

13 Bartlett WM. Demography Western Australia 1979. Catalogue No. 3101.5. Perth: Australian Bureau of Statistics, 1981.

14 Evans P, Johnson A, Mutch L, Alberman E. A standard form for recording clinical fi ndings in children with a motor defi cit of central origin. Developmental Medicine and Child Neurology 1989; 31: 119-127.

15 Bohannon RW, Smith MB. Physical Therapy 1987; 67: 206-207.

16 Palisano R, Rosenbaum P, Walter S, Russell D, Wood E, Galuppi B. Development and reliability of a system to classify gross motor function in children with cerebral palsy. Developmental Medicine and Child Neurology 1997; 39: 214-223.

17 Eliasson AC, Krumlinde-Sundholm L, Rösblad B, Beckung E, Arner M, Ohrvall AM, Rosenbaum P. The Manual Ability Classifi cation System (MACS) for children with cerebral palsy: scale development and evidence of validity and reliability. Developmental Medicine and Child Neurology 2006; 48: 549-554.

18 Bax M, Nelson KB. Birth asphyxia: a statement. Developmental Medicine and Child Neurology 1993; 35: 1015-1024.


19 Little Foundation Workshop. How can epidemiology and registers assist the prevention of cerebral palsy? The Western Australian Research Institute for Child Health, Perth, Western Australia, 1992.

20 Scher AI, Petterson B, Blair E, Ellenberg JH, Grether JK, Haan E, Reddihough DS, Yeargin-Allsopp M, Nelson KB. The risk of mortality or cerebral palsy in twins: A collaborative population-based study. Pediatric Research 2002; 52: 671-681.

21 Stanley FJ, Blair E, Alberman E. The Cerebral Palsies: Epidemiology and Causal Pathways. Appendix. Spastics International Medical Publications, Clinics in Developmental Medicine. London: Blackwells, 2000.

22 Reid S, Lanigan A, Walstab J, Reddihough D. Third Report of the Victorian Cerebral Palsy Register. Melbourne: Murdoch Childrens Research Institute, 2005.

23 Surman G, Newdick H, King A, Gallagher M, Kurinczuk JJ. 4Child: Four Counties Database of Cerebral Palsy, Vision Loss and Hearing Loss in Children. Annual Report 2004, including Data for Births 1984 to 1999. Oxford: National Perinatal Epidemiology Unit, 2005.

24 Himmelmann K, Hagberg G, Beckung E, Hagberg B, Uvebrant P. The changing panorama of cerebral palsy in Sweden. IX. Prevalence and origin in the birth-year period 1995-1998. Acta Paediatrica 2005; 94: 287-294

APPENDICES

APPENDIX A: Notifi cation card

APPENDIX B: Data collection form

APPENDIX C: Description of cerebral palsy form

APPENDIX D: Gross Motor Function Classifi cation System for Cerebral Palsy (Palisano et al, 1997)

APPENDIX E: Manual Ability Classifi cation System for Children with Cerebral Palsy (Eliasson et al, 2006)

APPENDIX F: Publications to July 2006


APPENDIX A: NOTIFICATION CARD

The notifi cation card is distributed to developmental paediatric centres to encourage notifi cation of cases to the Register. It is also used to request information on new cases where medical records cannot be accessed directly. It provides only suffi cient information to check whether a case is already on the Register and includes essential information not requested on the Description of Cerebral Palsy form (Appendix B), such as Where Born to identify cases born outside Western Australia, Postnatal cause and Date of death.


APPENDIX B: DATA COLLECTION FORM

The data collection form for the Western Australian Cerebral Palsy Register is printed on the front of a C4 size envelope (230 x 325 mm) which contains all paperwork related to a case. The reverse side of the envelope is printed with a series of 5 update entries. These are used to record the source and date of any new information obtained by phone, correspondence or record review.

The form shown on the following pages has recently been revised to refl ect the agreed minimum data set for the Australian Cerebral Palsy Register (ACPR) which can be viewed on the ACPR website (http://secure.cpregister-aus.com.au/),

Changes include the addition of validated motor function instruments which are increasingly being routinely recorded in the medical notes:

• the Gross Motor Function Classifi cation System for Cerebral Palsy (GMFCS) (Palisano et al, 1997) and

• the Manual Ability Classifi cation System for Children with Cerebral Palsy (MACS) (Eliasson et al, 2006).

These will eventually replace present motor severity codes (minimal, mild, moderate, severe) which are very loosely defi ned.

With the relevant ethics committee approvals, additional information about each case can be accessed through linkage with the following data sets:

• Midwives Notifi cations of Births (information regarding events during the pregnancy, labour, birth and newborn period)

• Western Australian Deaths File

• Western Australian Birth Defects Register

• Western Australian Hospital Morbidity Data




APPENDIX C: DESCRIPTION OF CEREBRAL PALSY

The form used to request information about cerebral palsy type, severity and associated disabilities is currently being redesigned. The previous form used since the late 1980s was adapted from the multiple box, limb-by-limb description of motor impairment created in the UK for the Oxford Register of Early Childhood Impairments (now 4Child). This has now been superseded by the Description of Cerebral Palsy form shown on the following pages which is being developed for the Australian Cerebral Palsy Register (ACPR).

The necessity for a new system of recording the clinical features of cerebral palsy arose when it was decided that the ACPR minimum data set would include fi ner spastic subcategories (monoplegia, hemiplegia, diplegia, triplegia, quadriplegia) than the broad categories of unilateral or bilateral spasticity adopted by the Surveillance of Cerebral Palsy in Europe (SCPE). In 2004 an initial Australia-wide survey conducted to ascertain a baseline level of agreement in classifying cerebral palsy found little inter- or intra-observer consistency in applying the classical terminology, and prompted the commencement of this work.

The new form aims to describe the clinical features of cerebral palsy rather than assign a classifi cation. It takes the multiple box system of recording motor impairments a step further by placing the boxes on stick fi gures and utilising more rigorous instruments to measure spasticity and functional abilities. It is also unique in that it is designed to be interpreted using computer software that will analyse the responses according to an algorithm that incorporates any desired set of defi nitions.

The Description of Cerebral Palsy form was introduced at workshops held at the Australasian Academy of Cerebral Palsy and Developmental Medicine (AusACPDM) in March 2006. After further modifi cation following feedback obtained from those workshops, it is presently being trialled nationally. A training DVD is also being developed, and a preliminary version of this is being used to present case studies to trial the form.




APPENDIX D: GROSS MOTOR FUNCTION CLASSIFICATION SYSTEM




APPENDIX E: MANUAL ABILITY CLASSIFICATION SYSTEM (MACS)

Printed from the MACS website at http://www.macs.nu/


APPENDIX F: CEREBRAL PALSY PUBLICATIONS (TO JULY 2006)

1. Stanley FJ. An epidemiological study of cerebral palsy in Western Australia, 1956-1975. I: Changes in total incidence of cerebral palsy and associated factors. Developmental Medicine and Child Neurology 1979; 21: 701-713.

2. Dale A, Stanley FJ. An epidemiological study of cerebral palsy in Western Australia, 1956-1975. II: Spastic cerebral palsy and perinatal factors. Developmental Medicine and Child Neurology 1980; 22: 13-25.

3. Stanley FJ. Low birthweight and cerebral palsy [letter]. The Lancet 1980; 1:1418.4. Stanley FJ. The epidemiology of cerebral palsy. In Araujo L (ed), Cerebral Palsy. Rio de Janeiro: Livra

Editora S.A.5. Stanley FJ. Neonatal mortality and cerebral palsy: The impact of neonatal intensive care. Australian

Paediatric Journal 1980; 16: 35-39.6. Stanley FJ. Spastic cerebral palsy: Changes in birthweight and gestational age. Early Human Development

1981; 5: 167-178.7. Stanley FJ, Atkinson S. The impact of neonatal intensive care on cerebral palsy in infants of low birthweight

[letter]. The Lancet 21 Nov 1981; ii: 1162.8. Blair E, Stanley FJ. An epidemiological study of cerebral palsy in Western Australia, 1956-1975. III:

Cerebral palsy of postnatal aetiology. Developmental Medicine and Child Neurology 1982; 24: 575-585.9. Stanley FJ. The use of a register in assessing the level of handicap in the community: The WA Cerebral

Palsy Register. Community Health Studies 1982; 6: 135-143.10. Stanley FJ. Using cerebral palsy data in the evaluation of neonatal intensive care: A warning. Developmental

Medicine and Child Neurology 1982; 24: 93-94.11. Atkinson S, Stanley FJ. Spastic diplegia in children of low and normal birthweight. Developmental

Medicine and Child Neurology 1983; 25: 693-708.12. French NP, Stanley FJ. The early detection of cerebral palsy. Maternal and Child Health 1983; 8: 407-

416.13. Stanley FJ, Alberman ED. The Epidemiology of the Cerebral Palsies. Spastics International Medical

Publications, Clinics in Developmental Medicine No. 87. Oxford: Blackwells Scientifi c Publications, 1984.

14. Stanley F, Blair E. Postnatal risk factors in the cerebral palsies. In Stanley FJ, Alberman ED (eds), The Epidemiology of the Cerebral Palsies. Spastics International Medical Publications, Clinics in Developmental Medicine No.87. Oxford: Blackwells Scientifi c Publications, 1984.

15. Stanley FJ, Watson L, Mauger S. The First Report of the Western Australian Cerebral Palsy Register. Perth: NH & MRC Research Unit in Epidemiology and Preventive Medicine, 1984.

16. Stanley FJ. Special registers. In S Leeder (ed) Handbook on Research Methodology. Transactions of Menzies Foundation Vol. 7, 1984: 51-60.

17. Blair E, Stanley FJ. Intra-uterine growth charts: Birthweight charts from a Western Australian population, for singleton caucasian livebirths after 21 weeks’ gestation. Commonwealth Department of Health. Canberra: Australian Government Publishing Service, 1985.

18. Blair E, Stanley FJ. Interobserver agreement in the classifi cation of cerebral palsy. Developmental Medicine and Child Neurology 1985; 27: 615-622.

19. Stanley FJ, Watson LD. Methodology of a cerebral palsy register: The Western Australian experience. Neuroepidemiology 1985; 4: 146.

20. Stanley FJ, English DR. Prevalence of and risk factors for cerebral palsy in a total population cohort of low birthweight (<2000g) infants. Developmental Medicine and Child Neurology 1986; 28: 559.


21. Stanley FJ. The Epidemiology of the Cerebral Palsies in Western Australia. MD Thesis, University of Western Australia, Perth, 1986.

22. Stanley FJ, Watson L, Mauger S. The Second Report of the Western Australian Cerebral Palsy Register. Perth: NHMRC Research Unit, 1987.

23. Stanley FJ. The changing face of cerebral palsy. Developmental Medicine and Child Neurology 1987; 29: 258-270.

24. Stanley FJ, Watson LD. The cerebral palsies in Western Australia: Trends, 1968 to 1981. American Journal of Obstetrics and Gynecology 1988; 158: 89-93.

25. Blair EM, Stanley FJ. Intrapartum asphyxia: A rare cause of cerebral palsy. Journal of Pediatrics 1988; 112: 515-519.

26. Bryce RL, Stanley FJ, Blair EM. The effects of intrapartum care on handicap. In M Enkin, M Keirse, I Chalmers (eds), Effective Care in Pregnancy and Childbirth. Oxford: OUP, 1988.

27. Blair EM, Stanley FJ. Minor morphogenetic anomalies re cerebral palsy [letter]. Journal of Pediatrics 1988; 133: 955.

28. Blair EM, Stanley FJ. Cerebral palsy in low birthweight infants [letter]. Developmental Medicine and Child Neurology 1988; 30: 550-553.

29. Stanley FJ, Chalmers I. Birth asphyxia, cerebral palsy and a shot in the foot. Editorial. The Lancet, 26 Nov 1989; ii: 1251-1252.

30. Stanley FJ. Cerebral palsy and multiple births [invited editorial]. Irish Medical Journal 1989; 82(3): 9731. Blair EM, Stanley FJ. Intrauterine growth and spastic cerebral palsy. I: The association of birthweight for

gestational age. American Journal of Obstetrics and Gynecology 1990; 162: 229-23732. Petterson B, Stanley FJ, Henderson D. Cerebral palsy in multiple births in Western Australia, 1956-80.

American Journal of Medical Genetics 1990; 37: 346-351.33. Stanley FJ, Blair EM. Why have we failed to reduce the frequency of cerebral palsy? Medical Journal of

Australia 1991; 154: 623-626.34. Stanley FJ, Blair E. Cerebral palsy and the quality of obstetric care. Cerebral Palsy Today 1992; 1(4):

1-3.35. Blair EM, Stanley FJ. Intrauterine growth and spastic cerebral palsy. II: The association with morphology

at birth. Early Human Development 1992; 28: 91-103.36. Stanley FJ. Survival and cerebral palsy in low birth weight infants: implications for perinatal care. Paediatric

and Perinatal Epidemiology 1992; 6: 298-310.37. Blair E, Stanley FJ, Hockey A. Intrapartum asphyxia and cerebral palsy [letter]. Journal of Pediatrics

1992; 121: 170-171.38. Stanley FJ, Watson LW. Trends in perinatal mortality and cerebral palsy in Western Australia. British

Medical Journal 1992; 304: 1658-1663.39. Stanley FJ. Trends in cerebral palsy in Western Australia [letter]. British Medical Journal 1992; 305: 525-

526.40. Stanley FJ, Blair E, Petterson B, Hockey A, Watson L. Spastic quadriplegia in Western Australia: A genetic

epidemiological study. I. The case population and perinatal risk factors. Developmental Medicine and Child Neurology 1993; 35: 191-201.

41. Petterson B, Stanley FJ. Spastic quadriplegia in Western Australia: A genetic epidemiological study. II. Pedigrees and family patterns of birth weight and gestational age. Developmental Medicine and Child Neurology 1993; 35: 202-215.

42. Blair E. A research defi nition for ‘birth asphyxia’? Developmental Medicine and Child Neurology 1993; 35: 449-455.


43. Blair E, Stanley FJ. When can spastic cerebral palsy be prevented? The generation of causal hypotheses by multivariate analysis of a case-control study. Paediatric and Perinatal Epidemiology 1993; 7: 272-301.

44. Blair E, Stanley FJ. Aetiological pathways to spastic cerebral palsy. Paediatric and Perinatal Epidemiology 1993; 7: 302-317.

45. Ballantyne J, Horsman S, Chauvel P, Blair E. Lycra splinting for the management of tone and posture in children with cerebral palsy [letter]. Developmental Medicine and Child Neurology 1993; 35: 456-457.

46. Petterson B, Nelson KB, Watson L, Stanley FJ. Twins, triplets and cerebral palsy in births in Western Australia in the 1980s. . British Medical Journal 1993; 307: 1239-1243.

47. Stanley FJ, Blair E. Cerebral palsy. In: Pless IB (ed), The Epidemiology of Childhood Disorders. New York: Oxford University Press, 1994.

48. Blair E, Morich P, Stanley F. Why do Aboriginal neonates weigh less? I. Gestational age: estimation, distribution and determinants. Australian and New Zealand Journal of Obstetrics and Gynecology 1994; 34: 158-163.

49. Stanley FJ. The aetiology of cerebral palsy. Early Human Development 1994; 36: 81-88.50. Stanley FJ. Cerebral palsy trends. Implications for perinatal care. Acta Obstetricia et Gynecologica

Scandinavica 1994; 73: 5-9.51. Stanley FJ. Cerebral palsy. The courts catch up with sad realities. Leading Article. The Medical Journal

of Australia 1994; 161: 236.52. Badawi N, Alessandri LM, Stanley FJ. Newer trends in practice in neurological disorders. Current Concepts

in Pediatrics, 1994: 309-314.53. Badawi N, Watson L, Lake B, Stanley FJ. Cerebral palsy. [Included as part of the Information Package

distributed by the Cerebral Palsy Association of WA]. Perth: Cerebral Palsy Association of WA, 1994.54. Palmer L, Petterson B, Blair E, Burton P. Family patterns of gestational age at delivery and growth in utero

in moderate and severe cerebral palsy. Developmental Medicine and Child Neurology 1994; 36: 1108-1119.

55. Blair E. The myth of fetal growth retardation at term [letter]. British Journal of Obstetrics and Gynaecology 1994; 101: 830-831.

56. Blair E. Cerebral palsy and intrapartum care: wrong denominator used [letter]. British Medical Journal 1994; 309: 1229.

57. Blair E. Report of information available in Western Australia concerning recent trends in childhood disability. Perth: Institute for Child Health Research, October 1994.

58. Badawi N, Watson L, Lake B, Alessandri L. Intellectual disability and cerebral palsy. In Banerjee SR (ed), Community and Social Pediatrics. New Delhi: Jaypee Brothers Medical Publishers, 1995: 1-13.

59. Stanley FJ, Blair E, Westaway J. Cerebral palsy. The role of obstetric care in pregnancy and delivery. A monograph for lawyers, parents and doctors. Perth: United Medical Defence, 1995.

60. Badawi N, Kurinczuk JJ, Keogh J, Blair E, Stanley F. Medico-legal aspects of birth asphyxia: A paediatrician’s perspective [letter]. J Paediatr Child Health 1995; 31: 57-59.

61. Palmer L, Petterson B, Blair E, Burton P. Antenatal antecedents of moderate and severe cerebral palsy. Paediatric and Perinatal Epidemiology 1995; 9: 171-184.

62. Blair E, Ballantyne J, Horsman S, Chauvel P. A study of a dynamic proximal stability splint in the management of children with cerebral palsy. Developmental Medicine and Child Neurology 1995; 37: 544-554.

63. Stanley FJ. Obstetrical responsibility for abnormal fetal outcome. In Chamberlain G (ed), Turnbull’s Obstetrics, 2nd Edition. London: Churchill Livingstone, 1995: 833-844.


64. Stanley FJ, Petterson B. Cerebral palsy in multiple births: the changing epidemiological patterns. In Ward RH and Whittle M (eds), Multiple Pregnancy. London: RCOG Press, 1995: 309-325.

65. Cans C, Lenoir S, Blair E, Verrier A, Haouari N, Rumeau-Rouquette C. Les defi ciences motrices de l’enfant: pour une clarifi cation nosologique dans les etudes epidemiologiques. Archives Pediatrie 1996; 3: 75-80.

66. Blair E, Palmer L, Stanley FJ. Cerebral palsy in very low birthweight infants, pre-eclampsia and magnesium sulphate [letter]. Pediatrics 1996; 97: 780-781.

67. Blair E, Ballantyne J, Horsman S, Chauvel P. A study of a dynamic proximal stability splint in the management of children with cerebral palsy. Reply. Developmental Medicine and Child Neurology 1996; 38: 182-183.

68. Blair E, Palmer L, Stanley FJ. Cerebral palsy in very low birthweight infants, pre-eclampsia and magnesium sulphate [letter]. Pediatrics 1996; 97: 780-781.

69. Gilles MT, Blair E, Watson L, Badawi N, Alessandri L, Dawes V, Plant AJ, Stanley FJ. Trauma in pregnancy and cerebral palsy: Is there a link? Med J Aust 1996; 164: 500-501.

70. Blair E. The undesirable consequences of controlling for birth weight in perinatal epidemiological studies. J Epidemiol Comm Health 1996; 50: 559-563.

71. Blair E. Can medical evidence be objectively assessed? Australian Health Law Bulletin 1996; 4: 73-77.72. Watson L, Stanley F, Petterson B. Rates of triplet pregnancies in Western Australia may be beginning to

fall [letter]. Brit Med J 1996; 313: 625-626.73. Blair EM, Shean RE. Trends in childhood disability. Med J Aust 1996; 165: 206-208.74. Badawi N, Kurinczuk JJ, Blair E, Keogh J, Stanley FJ. Early prediction of the development of microcephaly

after hypoxic-ischemic encephalopathy in the full term newborn [letter]. Pediatrics 1996; 97: 151-152.75. Blair E, Ballantyne J, Horsman S, Chauvel P. A study of a dynamic proximal stability splint in the management

of children with cerebral palsy. Reply. Dev Med Child Neurol 1996; 38: 182-183.76. Blair E. Why do Aboriginal newborns weigh less? Determinants of birthweight for gestation. J Paediatr

Child Health 1996; 32: 498-503.77. Blair E. Model to identify potentially preventable cerebral palsy of intrapartum origin [letter]. Arch Dis Child

1996; 75: F143-F144.78. Blair E. Obstetric antecedents of cerebral palsy. Fetal and Maternal Medicine Review 1996; 8: 199-215.79. Blair E. The undesirable consequences of controlling for birth weight in perinatal epidemiological studies.

J Epidemiol Comm Health 1996; 50: 559-563.80. Blair E, Stanley FJ. Issues in the classifi cation and epidemiology of cerebral palsy [invited review]. Mental

Retardation and Developmental Disabilities Research Reviews 1997; 3: 184-193.81. Stanley FJ, Badawi N. Introduction. The Role of Epidemiology and Perinatal Databases for both research

and care. Seminars in Neonatology 1997; 2: 147-148.82. Badawi N, Kurinczuk JJ, Hall D, Field D, Pemberton PJ, Stanley FJ. Newborn encephalopathy in term

infants: three approaches to population-based investigation. Seminars in Neonatology 1997; 2: 181-188.83. Stanley FJ, Read AW, Kurinczuk JJ, Croft ML, Bower C. A population maternal and child health research

database for research and policy evaluation in Western Australia. Seminars in Neonatology 1997; 2: 195-202.

84. Pharoah POD, Platt MJ, Blair E, Cooke T. Cerebral palsy registers. Seminars in Neonatology 1997; 2: 203-210.

85. Stanley F. Prenatal determinants of motor disorders. Acta Paediatr Suppl 1997; 422: 92-102.86. Blair E. Antecedents of cerebral palsy in a multicenter trial of indomethacin for intraventricular hemorrhage

[letter]. Arch Pediatr Adolesc Med 1997; 151: 1269-1270.


87. Petterson B, Blair E, Watson L, Stanley F. Adverse outcome after multiple pregnancy. Bailliere’s Clinical Obstetrics and Gynaecology 1998; 12: 1-17.

88. Badawi N, Watson L, Petterson B, Blair E, Slee J, Haan E, Stanley FJ. What constitutes cerebral palsy? Developmental Medicine and Child Neurology 1998; 40: 520-527.

89. Blair E. Risk factors for cerebral palsy: a case control study in Greece [letter]. Scand J Soc Med 1998; 26; 300-301.

90. MacLennan A for the International Cerebral Palsy Task Force. A template for defi ning a causal relation between acute intrapartum events and cerebral palsy: international consensus statement. British Medical Journal 1999; 319: 1054-1059.

91. Watson L, Stanley F, Blair E. Report of the Western Australian Cerebral Palsy Register to Birth Year 1994. Perth: TVW Telethon Institute for Child Health Research, Dec 1999.

92. Blair E. 2000. More on asphyxia, cerebral palsy and litigation. Australian and New Zealand Journal of Obstetrics and Gynaecology 2000; 40(1): 93-96.

93. Blair E. Australian national birthweight percentiles by gestational age [letter]. Medical Journal of Australia 1999; 171; 53.

94. Blair E, Wallman A. Changing rates of severity of cerebral palsy and implications for practice. Action Packed 2000, 5(3): 18-20.

95. Baker P, Kingdom J, Blair E. Defi nitions of intrauterine growth restriction. In P Baker, J Kingdom (eds), Intrauterine Growth Restriction. London: Springer-Verlag, 2000.

96. Blair E. Paediatric implications of intrauterine growth restriction with special reference to cerebral palsy. In P Baker, J Kingdom (eds), Intrauterine Growth Restriction. London: Springer-Verlag, 2000.

97. Stanley FJ, Alberman ED, Blair E. The Cerebral Palsies: Epidemiology and Causal Pathways. Spastics International Medical Publications, Clinics in Developmental Medicine. London: Blackwells, 2000.

98. Blair E, Love S, Valentine J. Proportional change: an aid to the reporting of technical and functional outcomes when evaluating clinical interventions. European Journal of Neurology 2001; 8(Suppl 5): 178-182.

99. Love S, Valentine J, Blair E, Price C. The effect of Botulinum toxin-A on functional ability. European Journal of Neurology 2001; 8(Suppl 5): 50-58 (awarded Butterworth/Heinemann Prize).

100. Blair E, Stanley FJ. The epidemiology of the cerebral palsies. In Levene MI, Cherenak FA, Whittle M (eds), Fetal and Neonatal Neurology and Neurosurgery, Third Edition. London: Churchill Livingstone, 2001: 791-798.

101. Stanley F, Blair E, Alberman E. Claim that events before birth cause cerebral palsy is disputed. British Medical Journal 2001; 322: 50.

102. Blair E, Watson L, Badawi N, Stanley FJ. Life expectancy among people with cerebral palsy in Western Australia. Developmental Medicine and Child Neurology 2001; 43: 508-515.

103. Blair E. Life expectancy among people with cerebral palsy in Western Australia [letter]. Developmental Medicine and Child Neurology 2001; 43: 792.

104. Stanley F, Blair E. Obstetrical responsibility for abnormal fetal or neonatal outcome. In Chamberlain G (ed) Turnbull’s Obstetrics, Third edition. London: Churchill Livingstone, 2001: 709-719.

105. Blair E. Dealing with measures – an epidemiologist’s viewpoint. Australasian Academy of Cerebral Palsy and Developmental Medicine Newsletter 2001; 1; 3-8.

106. Blair E. Trends in cerebral palsy. Indian Journal of Paediatrics 2001; 68: 433-438.107. Blair E, Stanley F. Causal pathways to cerebral palsy. Current Paediatrics 2002; 12(3): 179-185.108. Blair E, Stanley F. New thoughts on the aetiology of cerebral palsy. In Sturdee D, Olah K, Purdie D, Keane

D (eds), The Yearbook of Obstetrics and Gynecology, Volume 10. London: RCOG Press, 2002: 357-367.


109. Camfi eld CS, Camfi eld P, Watson L. Cerebral palsy in children with epilepsy. In Devinsky O, Westbrook LE (eds), Epilepsy and Developmental Disabilities. Boston: Butterworth-Heinemann, 2002.

110. Petterson B, Watson L, Kurinczuk JJ. Cerebral palsy in triplets. In Keith LG, Blickstein I (eds), Triplet Pregnancies and Their Consequences. New York: Parthenon Publishing Group, 2002.

111. Morley R, Owens J, Blair E, Dwyer T. Is birthweight a good marker for gestational exposures that increase the risk of adult disease? Paediatric and Perinatal Epidemiology 2002; 16: 194-199.

112. Liu C, Blair E. Predicted birth weight for singletons and twins. Twin Research 2002; 5(6): 529-537.113. Blair E. Legal maze added pain for disabled [Opinion article]. The West Australian, 8 May 2003: 23. 114. Blair E. Uses and misuses of the percentile (centile or quantile) position. Australian Epidemiologist 2003;

10(1): 26-28.115. Blair E. Where does – and where should – the money come from? Disparity: policy practice and argument

[cover article]. ACROD Winter 2003: 16-20.116. Blair E, de Klerk N. Causal pathways: implications for analysis. Australasian Epidemiologist (Epidemiological

Methods) 2004; 11(1): 3-6.117. Blair E, Liu Y, Cosgrove P. Choosing the best estimate of gestational age from routinely collected population-

based perinatal data. Paediatric and Perinatal Epidemiology 2004; 18: 270-276. 118. Blair E. Gold is not always good enough: the shortcomings of randomisation when evaluating interventions

in small heterogeneous populations. Journal of Clinical Epidemiology 2004; 57(12): 1219-1222.119. Leviton A, Blair E, Dammann O, Allred E. The wealth of information conveyed by gestational age. Journal

of Pediatrics 2005; 146: 123-127. 120. Bourke J, Bower C, Blair E, Knuiman, M The effect of terminations on the estimated perinatal mortality

rates. Paediatric and Perinatal Epidemiology 2005; 19: 284-293 121. Blair E, Liu Y, de Klerk N, Lawrence D. Optimal fetal growth for the Caucasian singleton and assessment of

appropriateness of fetal growth: analysis of a total population perinatal database. BMC Paediatrics 2005; 5: 13. http://www.biomedcentral.com//1471-2431/5/13

122. Blair E, Love S. Defi nition and classifi cation of cerebral palsy [Invited Commentary]. Developmental Medicine and Child Neurology 2005; 47: 510.

123. Waters E, Davis E, Reddihough D, Graham HK, MacKinnon A, Wolfe R, Stevenson R, Bjornsen K, Blair E, Hoare P, Ravens-Sieber U, Boyd R. A new condition specifi c quality of life scale for children with cerebral palsy. PRO Newsletter 2005; 35: 10-12.

124. Blair E, Watson L. Epidemiology of cerebral palsy. In Doyle L (ed), Perinatal and Neonatal Epidemiology, Seminars in Fetal and Neonatal Medicine 2006; 11: 117-1125

125. The Australian Cerebral Palsy Register. Proposed new defi nition of cerebral palsy does not solve any of the problems of existing defi nitions. Developmental Medicine and Child Neurology 2006; 48: 78.

126. Blair E. Trends in cerebral palsy prevalence in Northern Ireland, 1981-1997 [Invited Commentary]. Developmental Medicine and Child Neurology 2006; 48: 405.

127. Jarvis S, Glinianaia S, Blair E. Intrauterine growth and cerebral palsy. In Hermansen MC (ed) Perinatal Causes of Cerebral Palsy, Clinics in Perinatology 2006; 33(2): 285-300.

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REPORT OF THE WESTERN AUSTRALIAN …/media/Files/Hospitals...REPORT OF THE WESTERN AUSTRALIAN CEREBRAL PALSY REGISTER TO BIRTH YEAR 1999 Linda Watson Eve Blair, PhD Fiona Stanley AC