An Overview Of TheALSPAC Data Resource

RSS Avon Local Group Meeting26th May 2009

David Herrickdavid.herrick@bristol.ac.uk

http://www.bristol.ac.uk/alspac/

What is ALSPAC?

“Avon Longitudinal Study of Parents and Children”

Cohort study of children and their parents, based in the former county of Avon (excluding Bath)

Designed to determine ways in which the individual’s genotype combines with environmental pressures to influence health and development

Study design

Eligibility criteria: Mothers had to be resident in the study area and have an expected date of delivery between 1st April 1991 and 31st December 1992

Avon was broadly representative of the UK as a whole and has a relatively stable population

Core sample of 14,541 pregnancies resulting in 14,062 live born children

Data Sources

Self Completion Questionnaires Hands on Assessments Biological Samples DNA Direct School Contact Health Records Linked Datasets Sub Studies

Self completion questionnaires (1)

Carer (17, 4 during pregnancy)• Mother’s health, home environment, income,

education, employment etc. Partner (15, 2 during pregnancy) Child-based, completed by main carer (23)

• Child’s health, development, behaviour, diet etc. Child-completed (22)

• Teeth, school, home, hobbies, substance use, mental health etc.

Annual puberty questionnaires (9)• Tanner staging, menarchy

Self completion questionnaires (2)

Miscarriages Adult Learning (Carer & Partner)

• Single mail shot; follow up telephone interview

DCSF Year 11 (Carer & Child)• Education - attitudes & aspirations

Friendships (Child)• Single mail shot; aim to identify which other study

children child is friends with

Hands on assessments (1) Children in Focus

• 10% sample seen 10 times between 4 & 61 months• 1432 attended at least 1, 1000 at least 8, 539 all 10• Physical measures: Anthropometry, blood pressure,

lung function, skin, hair & eye observations, allergy testing, vision, hearing, dental

• Cognitive measures: habituation, memory, speech• Environmental measures: diet, pollution, parenting,

day care• Blood samples

Hands on assessments (2) Focus Sessions

• Annual assessments, starting with Focus@7, to which the whole cohort is invited

• Physical: Measures, bone density, fitness, vision, hearing, allergies, blood / saliva samples, vascular function, lung function, acne

• Cognitive / behavioural: IQ, speech & language, bullying, antisocial activities, friends, substance use, romantic relations, psychosis, depression

Biological samples

Maternal blood & urine Paternal blood & saliva Umbilical cord blood & slices Placentas Children’s teeth, hair and nail

clippings Children’s blood, saliva & urine

DNA DNA for:

• ~10,000 children• ~10,000 mothers• ~1,000 partners

~6700 mother/child pairs ~700 trios Blood for cell lines for:

• ~7,000 children• ~5,700 mothers• ~1,400 fathers

ALSPAC at School

Children born between:

Apr 1991& Aug 1991

Sep 1991& Aug 1992

Sep 1992

& Dec 1992

Reception 1995 1996 1997

Key Stage 1 1998 1999 2000

Key Stage 2 2002 2003 2004

Key Stage 3 2005 2006 2007

GCSE 2007 2008 2009

Direct School Contact (1)

Contact with ~350 primary schools in the four local LEAs:• Bristol• South Gloucestershire• North Somerset• Bath and North East Somerset

Private & special schools included Parental contact for out of area cases

Direct School Contact (2)

Questionnaires in Year 3 & Year 6:• School (Head teacher)• Class (Class teacher)• Child (Class teacher)

Maths test in Year 4 Maths, Spelling & Science tests in Year 6 Year 6 maths test repeated in Year 8

Health Records

Delivery notes• Abstracted by midwives• ~ 8300 in full• ~ 2300 shortened version• ~ 2000 further planned

Convulsions (n 400)• Hospital admissions• Selected from questionnaire responses

Special Care Baby Unit (n 1000)

Linked Datasets

ONS Tracing Electronic antenatal & birth records National Pupil Database Address based Currently investigating PCT data,

HES, Home Office, DWP, HESA

Sub Studies (1) Avon Brothers and Sisters Study Becoming a Teenager Before Breakfast Study Being 3 British Gas Study Bunk Bed Study DATE (diet and physical activity study) Deuterium Family Study Four Seasons (physical activity calibration study)

Sub Studies (2) Fractures Identifying Developmental Impairments K4 (physical activity calibration study) Lightbox (as an alternative to anthropometery) Noise Study Peanut & Other Allergies Scan and Swim Teenager at Thirteen Twins Secret Language

Response Figures

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Age of child (years)

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Carer Partner Child based Child Completed Puberty Focus Key Stage

Jan 2002

Data Access Model Contact ALSPAC via email Receive CD/Download guide to Data sets Download Research Proposal Form

• Incorporates Data Agreement Form Submit proposal to ALSPAC Exec Receive dataset limited to research

question/s • Variables are identified by collaborator• Built by ALSPAC statisticians/data staff

Extensions require further submission

Publications

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