The assessment of food related problems in individuals

Assessing food related problems

1

The assessment of food related problems in

individuals with Prader-Willi syndrome.

Russell, H. & Oliver, C.

Cerebra Centre for Neurodevelopmental Disorders,

School of Psychology,

University of Birmingham

Please use this reference when citing this work:

Russell, H. & Oliver, C. (2003). The assessment of food related problems in individuals with

Prader-Willi syndrome. British Journal of Clinical Psychology, 42, 379-392.

The Cerebra Centre for Neurodevelopmental Disorders, School of Psychology, University of Birmingham, Edgbaston, Birmingham, B15 2TT Website: www.cndd.Bham.ac.uk E-mail: [email protected]


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Abstract

The development of a twenty item questionnaire, the Food Related Problem Questionnaire (FRPQ),

with four subscales (preoccupation with food, impairment of satiety, difficulty with self-control and

other food-related 'challenging' behaviour of food-related problems) for use with individuals with

Prader-Willi syndrome (PWS) is described.. Test-retest and inter-rater reliability for the total score

are .78 and .86 respectively. Subscale test-retest and inter-rater reliability are acceptable for three

subscales (range .70 to .85) but not for the self control subscale. To establish criterion validity,

scores on the FRPQ for a sample of individuals with PWS were compared to scores for individuals

with intellectual disability but not PWS. All reliable subscale scores and the total score

differentiated between the groups (p<.001 in all cases). Internal consistency for the total scale is

good (Cronbach’s Alpha = .87). Finally, some normative data for a limited age range are presented

and potential applications of the measure are discussed.


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Introduction

There is increasing interest in the concept of behavioural phenotypes within the field of intellectual

disability. There is little doubt that in some syndromes specific behaviours are more prevalent than

might be expected by chance. Three well documented examples are self-biting in Lesch-Nyhan

syndrome (Christie et al., 1982), stereotyped hand-wringing movements in Rett syndrome (Kerr &

Stephenson, 1985) and excessive laughing and smiling in Angelman syndrome (Summers et al.,

1995). Psychology has an important role to play in this emerging area. For example, examining the

effects of the environment on behaviours purported to be part of a behavioural phenotype (see: Hall

et al., 2001; Oliver et al., 1993, 2002) and the influence of the concept of behavioural phenotype on

the attributions of others (see: Hyman & Oliver, 2001). Additionally, it is important that relevant

measures with robust psychometric properties are developed to accurately document behavioural

phenotypes and examine with syndrome variability.

Excessive eating (hyperphagia) is a significant feature of Prader-Willi Syndrome (PWS; Holm et

al., 1993) and first becomes apparent between the ages of two and six years (Cassidy, 1984; Ehara

et al., 1993). Initially, a child's increased appetite may be welcomed by parents, as prior to this,

hypotonia (low muscle tone) may have contributed to feeding difficulties and 'failure to thrive'

(Greenberg et al., 1987). However, over time a child's interest in food may become debilitating,

both for the young person with PWS and for those around them (Greenswag, 1987; Clarke et al.,

1995) with two primary consequences of overeating described: obesity and behavioural problems.

Gross obesity has been widely reported in children and adults with PWS if overeating is left

unchecked (Butler, 1990; Holm et al., 1993) and individuals are noted to require a lower calorie

diet than individuals without the syndrome to stay within normal weight limits (Pipes & Holm,


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1973). Decreased physical exercise and lowered energy expenditure have been identified as

exacerbating the problem (Butler, 1990; Davies & Joughin, 1993). Physical health problems

associated with weight gain have been reported including: diabetes mellitus (Laurance et al., 1981),

coronary artery disease (Lamb & Johnson, 1987) and premature death (Laurance et al., 1981). The

psychological impact of being overweight may also be detrimental, contributing to difficulties in

forming relationships with peers (Dykens et al., 1992) and in turn affecting an individuals' self-

worth (Wolfensberger, 2000).

An impaired satiety mechanism has been postulated as responsible for overeating (Laurance, 1993;

Holland, 1998) and Dykens et al. (1997) suggests that hyperphagia is a biologically-driven

behaviour. Support for a biological basis to voracious eating behaviour has been offered by Holland

et al. (1995) who found that individuals with PWS required a larger quantity of food and had

greater difficulty recognising when they were satiated compared with a control group. The notion

of overeating as a physiologically-driven behaviour is also evident in the ways that a person's food

intake is managed. External controls such as locks on fridge doors and carers controlling size of

meals have been suggested as effective strategies (Whitman & Greenswag, 1995) and appetite-

suppressive medications have been prescribed (Dech & Budow, 1991), although with mixed results

(Jun-Bi Tu et al. 1992). However, these approaches to food management have been criticised.

Gordon & Clarke-Bruyn (1991) propose that if excessive eating is viewed as an inevitable

consequence of PWS, carers may be reluctant to intervene and individuals with PWS may be

stigmatised (Levine, 1995). Furthermore, restricting a person's access to food is controversial and

has fuelled a debate about the degree to which a person may be viewed as an autonomous

individual capable of making food-related decisions (Dykens et al. 1997; Holland & Wong, in

press).


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A range of food-related behavioural difficulties are also reported in the PWS literature, including

taking food from others (Donaldson et al., 1994), stealing money to purchase food (Sherman,

1995), hoarding food items (Dykens et al., 1996) and lifting a kitchen door from its hinges in order

to gain access to food (Benjamin & Buot-Smith, 1993). The ways in which individuals seek to

obtain food are also described as ‘manipulative’ and 'ingenious' (Donaldson et al. 1994). However,

these descriptions are based on anecdotal reports of a few people with PWS. How characteristic

such behavioural difficulties are of the broader PWS population is unknown. More recently,

Sarimski (1996) systematically investigated food-related behavioural difficulties in a group of

twenty-eight children with PWS using the 'Children's Eating Behaviour Inventory' (CEBI; Archer

et al., 1991). Sarimski (1996) reported that 'food-seeking behaviours', such as asking for food

between meals and hiding food, characterised children with PWS in comparison to children with

Williams-Beuren syndrome, although significant variability in food-seeking behaviours of children

with PWS was also found. This study employed a relatively small cohort of children within a

limited age range and employs an eating behaviour measure used with children from the general

population. Food-related behaviours specific to individuals with PWS may therefore be omitted.

Consequently, the findings of this study might not comprise the full range of eating-related

problems.

Excessive eating has also been described as a feature of people who binge eat (Beglin & Fairburn,

1992; Fairburn & Wilson, 1993; McManus & Waller, 1995) and is reported as a characteristic of

Kleine-Levin syndrome (Critchley, 1962) and Tourette's syndrome (Ballard, 1992). A number of

measures have been used to assess aspects of eating in the broader eating disorder population (eg.

'Eating Attitudes Test', Garner et al., 1982; 'Mizes Anorectic Cognitions Questionnaire', Mizes &

Klesges, 1989; 'Eating Disorders Inventory', Garner, 1991). However, these measures are reliant on


6

self-report and also do not incorporate all aspects of eating behaviour described in individuals with

PWS. They are therefore of limited use within the PWS population.

Clearly, a need exists to systematically investigate the eating behaviour of individuals with PWS.

This would be beneficial both in examining global statements of food-related problems associated

with PWS, the relationship between food-related problems and other behaviours and characteristics

and would offer a measure of treatment efficacy. The principal aim of the current study is to

describe the development of a questionnaire for measuring food-related problems in adults with

PWS. Test-retest and inter-rater reliability for the questionnaire are reported. As a measure of

validity the extent to which the questionnaire is able to differentiate between food-related problems

characteristic of individuals with PWS versus individuals from the wider intellectual disability

population is reported and internal consistency of the questionnaire is assessed.

Method

Development of the Food Related Problems Questionnaire

To ascertain the range of difficulties regarding food-related issues, semi-structured interviews were

conducted with parents and carers of 12 individuals with PWS, of whom 6 (50%) were female.

Families of individuals with PWS were identified via the Prader-Willi syndrome Association

(PWSA, UK) and were all members of a local support group. Mean age of females was 9.8 years

(age range 8 - 21 years) and mean age of males was 17 years (age range 8 -24 years). During the

semi-structured interviews, which focussed on all aspects of food-related behaviour, individual

problems reported by informants were noted. Following the interviews, recorded individual

problems were clustered according to themes and sixteen questions which captured the breadth of


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the difficulties described were constructed. Although no formal reliability analysis of the reported

problems was conducted, clustering by themes was achieved by consensus.

To derive subscales the twenty items were grouped under different elements of food-related issues

and operational definitions derived for each of these elements. To assess the reliability of the

allocation of items to subscales a psychologist then classified each question using the operational

definitions provided. 90% inter-rater agreement was established. A second psychologist repeated

this procedure and 100% inter-rater agreement was obtained. The operational definitions and

principal subscales generated with questions allocated to each subscale are shown in Table 1.

+++++++++++ Insert Table 1 here +++++++++++++

For each item a 7 point Likert scale response format was used with responses ranging from 0 =

'never' to 6 = 'always.' A further response 'does not apply' was included for six items that asked

about verbal responses. In addition, three open-ended questions were included that asked about:

external control, evidence of self-control and other comments. The maximum possible score for the

total FRPQ is 96. The maximum scores for each subscale are shown in Table 1.

Participants

Three groups of participants were recruited (PWS specialist residential group, comparison

residential group and PWS community group). The PWS specialist residential group and the

comparison residential group were employed for analyses examining inter-rater and test-retest

reliability and criterion validity. Participants were drawn from a sample of 65 individuals with

intellectual disabilities living in one of six staffed community-based homes. All six homes were

located within the same geographical area and existed under one umbrella organisation.


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Participants were either: adults with a diagnosis of Prader-Willi syndrome (PWS specialist

residential group), or adults with intellectual disabilities without PWS (comparison residential

group). The residential homes were designed around the specific needs of adults with PWS; in

particular, food was locked away and the quantity of food restricted. Consent to participate in the

study was gained from 38 (58.5%) individuals: 24 (72.7%) adults with PWS and 14 (43.7%) adults

with intellectual disabilities without PWS. Prior to analysis questionnaires were screened to

identify and exclude potential participants scoring 7 (‘does not apply’) on two or more items that

asked about verbal responses. This was done to avoid a low score as a result of limited verbal

capacity. The screening procedure led to the exclusion of one individual with PWS and one

individual with intellectual disabilities without PWS.

Demographic information was collected concerning the respondent's relationship to the participant,

sex and age of the individual, daytime activities and prescribed medication. Descriptors ranging

from 'profound' to 'superior' were included to gauge level of intellectual functioning. Keyworkers

were also asked about the age at which a diagnosis was made and how this was ascertained.

PWS Specialist Residential Group. The mean age of individuals with PWS (N = 23) was 27.7 years

(SD = 6.5; range 19 to 38.9 years) and 8 (34.8%) participants were female. 10 (43.5%) adults

attended college and 7 (30.4%) adults attended onsite workrooms. In the month prior to the study, a

range of medication had been prescribed. 11 (47.8%) participants had been prescribed antipsychotic

medication and 7 (30.4%) participants had been prescribed antidepressant medication. Insufficient

information was available regarding level of intellectual functioning. All participants had received

a clinical diagnosis of PWS.


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Comparison Residential Group. The mean age of the residential comparison group (N =12) was

43.1 years (SD = 5.2; age range 33 to 51.9 years) and 5 (41.7%) were female. 4 (33.3%)

participants attended college and 6 (50%) attended onsite workrooms. 8 (66.7%) of individuals had

been prescribed antipsychotic medication and 3 (25%) had been prescribed antidepressant

medication. Insufficient information was available regarding level of intellectual functioning.

The PWS community group were recruited to increase the sample size in order to evaluate internal

consistency and concurrent validity.

Recruitment Procedure

As part of a larger study (Russell and Oliver, submitted) 99 questionnaire packs were sent to carers

of individuals with PWS in the United Kingdom. Questionnaires were sent by the Prader-Willi

Syndrome Association (PWSA, UK). Carers identified via an earlier postal questionnaire as being

willing to participate in future research were contacted. The questionnaires consisted of questions

regarding demographic details, three standardised measures and the FRPQ developed in the current

study. Included in each pack was a covering letter, participant information and a reply paid

envelope. As in study 1, prior to analysis questionnaires were screened to identify and exclude

potential participants scoring 7 (‘does not apply’) on two or more items that asked about verbal

responses. This was done to avoid a low score as a result of limited verbal capacity. The screening

procedure led to the exclusion of two individuals with PWS from 60 respondents.

PWS Community Group. 58 individuals with Prader-Willi syndrome were recruited via the Prader-

Willi Syndrome Association (PWSA, UK), a parent support group for children diagnosed with

PWS. 45 (77.6%) questionnaires were completed by the mother, 7 (12.1%) by the father, 1 (1.7%)

by both parents and 5 (8.6%) by an another person which included residential care staff and foster

carers. Of the 58 participants identified, 31 (53.4%) were female and the total sample ranged in age


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from 14.4 to 22.1 years (mean = 18.3, SD = 2.19). The age when the individual was diagnosed with

PWS ranged from birth to 17 years (mean = 4.1, SD = 4.7). For 28 participants (48.3%) diagnosis

was made based on clinical symptoms alone, 21 (36.2%) following genetic testing and 5 (8.6%)

following both procedures. Method of diagnosis was not stated for the remaining 4 participants.

34 (58.6%) carers stated that the individual with PWS had completed an assessment of intelligence

and of those whose IQ score was known (N = 27), participants were reported to fall within the mild

range of intellectual disabilities. 25 (43.1%) participants attended college and 15 (25.9%) attended

a special school. The remaining 18 attended a range of daytime facilities. In the month prior to the

questionnaire being completed, a range of medication had been described, notably 4 (6.9%)

participants had been prescribed antipsychotic medication and 2 (3.4%) participants had been

prescribed antidepressant medication.

Design and Data Analysis

Inter-Rater and Test-Retest Reliability

Two independent groups of raters completed the FRPQ to assess inter-rater reliability. The General

Manager of the group homes distributed the FRPQ to the named keyworker of the 35 individuals in

the PWS specialist residential group and residential comparison group and to a second carer

known to the individual. To ensure that questions were answered independently, respondents were

instructed not to confer with other carers. Test-retest reliability was assessed by asking the named

keyworker to complete the FRPQ on a two occasions separated by a two to three-week period. To

ensure that the second ratings were completed without reference to earlier responses, questionnaires

completed at time one were collected prior to distribution of the questionnaires at time two.

Criterion Validity, Concurrent Validity and Internal Consistency


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To evaluate the validity of the FRPQ, two strategies were adopted. First, to evaluate criterion

validity, subscales and total score were compared for individuals with in the PWS specialist

residential group and the residential comparison group residing in the same community-based

group homes. Second, to partially evaluate concurrent validity, responses for relevant subscales on

the FRPQ were compared with responses to similar question items on the Checklist of Challenging

Behaviour (CCB; Harris, Humphreys & Thomson, 1994).

Results

Prior to analysis questionnaires were examined to evaluate the number of participants for whom

‘does not apply’ was indicated. In the PWS specialist residential group this was indicated for two

participants on one item, for the residential comparison group this was indicated for one participant

on one item. The results were analysed for each pair of raters (inter-rater reliability) and the same

raters on two separate occasions (test-retest reliability) using Pearson correlation coefficients. The

mean coefficient for inter-rater reliability at item level was .53 (range .05 to .91) and the mean

coefficient for test-retest reliability at item level was .57 (range -.01 to .93). The inter-rater and test-

retest reliability levels for subscales and total score of the FRPQ are presented in Table 2.


Inter-rater and test-retest reliability varied across subscales. Adequate inter-rater reliability was

established for all of the subscales (r = .56 to .89) and adequate test-retest reliability was

established for six out of the seven subscales (r = .64 to .85).

Criterion validity


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In order to examine whether the FRPQ was able to distinguish between distinct groups, scores

obtained for individuals with PWS were compared with those with an intellectual disability without

the syndrome. Both cohorts resided within the same community setting; thus it was hypothesised

that any differences noted between groups may be attributed to the degree of food-related

problems, rather than being attributable to environmental factors. Independent samples t-tests were

employed and the results are summarised in Table 3.


In Table 3 it can be seen that the mean scores for the two groups differ on all subscales and total

score, with the PWS cohort scoring consistently higher than the comparison group on all subscales.

Concurrent validity

A second approach to validating some items of the FRPQ was to examine the level of

correspondence between responses to items on the questionnaire with similar items on an existing

measure. The Checklist of Challenging Behaviour (CCB; Harris, Humphreys & Thomson, 1994)

was used for this purpose. The CCB consists of two parts with items about aggressive behaviours

and self-injury (Part I) and other challenging behaviours (Part II). Named keyworkers involved in

development of the FRPQ completed the CCB when providing demographic information and rating

the FRPQ for the first time. For the purposes of validation, two categories forming part of the

subscale 'composite negative behaviour' of the FRPQ were compared with responses to two

statements on the CCB. An independent samples t-test was carried out to compare scores on the

subscale 'takes/stores food' (comprising items 2, 4 and 8 on the FRPQ) of participants identified as:

'Taking food or drink from others?' on the CCB with those who were not. A significant difference

on the FRPQ (t (52) = 4.6, p < .0001) was found between those reported to take food or drink on


13

the CCB (mean = 13.3, SD = 3.6) and those reported not to take food or drink on the CCB (mean =

7.7, SD = 4.8). A second independent samples t-test was carried out to compare the scores on the

subscale 'eats inedible items' (comprising items 12 and 15 on the FRPQ) on the CCB item: 'Eating

inappropriate things (eg rubbish, faeces, dangerous objects).' A significant difference on the FRPQ

(t (51) = 5.39, p < .0001) was found between those who were reported to show pica on the CCB

(mean = 6.7, SD = 2.6) and those for whom pica was not reported on the CCB (mean = .85, SD =

1.3).

Internal Consistency

Independent samples t-tests were carried out to compare scores of individuals with in the PWS

specialist residential group with individuals in the PWS community group (see Table 4). This was

undertaken to establish whether results obtained during development of the measure were specific

to the specialist residential group or typical of the broader PWS population. As can be seen in Table

4, the two groups did not significantly differ on the subscales: impairment of satiety and composite

negative behaviour. However, difference on the subscale 'preoccupation with food' was significant

(p < .01), with participants in the PWS community group being reported to be more preoccupied

with food (mean = 10.63, sd = 3.96) than participants living in PWS-designed group homes (mean

= 8.1, sd = 2.8).


To establish internal consistency, Cronbach's alpha coefficient was calculated. Participants from all

three groups were included in the analysis. Nunnally (1978) states the generally accepted standard

for reliability estimates to be above .70 (Huck & Cormier, 1996). In this study, Cronbach's alpha


14

coefficient of .87 was determined for the total score of the FRPQ, suggesting good internal

consistency.

Discussion

The study presents reliability and validity data on an informant-based measure of food-related

problems in adults with PWS. Adequate inter-rater and test-retest reliability were demonstrated for

all of the subscales. Several items within subscales were found to be unreliable. However, the

purpose of each subscale was to measure a specific construct. Hence, reliability for subscales need

only be measured. Therefore, it is important that the results of the FRPQ are only considered at the

subscale level and not at the item level. The measure was also found to be suitable for assessing

food-related problems in people with PWS regardless of setting and to successfully differentiate

individuals with PWS from those with intellectual disabilities (criterion validity). Finally, good

internal consistency was demonstrated.

This study is a preliminary investigation of difference regarding food-related problems in two

distinct groups. Individuals with PWS scored higher on the FRPQ than individuals with intellectual

disabilities without the syndrome. However, significant variability in aspects of food-related

problems were found between groups. Noticeably, individuals with intellectual disabilites scored

significantly lower on subcategories of the subscale 'composite negative behaviour' compared with

the PWS group and no behavioural difficulties were reported for some people. These findings are

consistent with those reported by Sarimski (1996) in a study investigating 'food-seeking behaviours'

in children with Prader-Willi and Williams-Beuren syndrome. Further studies are needed to

delineate aspects of food-related problems that characterise individuals with PWS (i.e. syndrome-

specific behaviours) and food issues that may be problematic for more than one population.


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There are a number of limitations to consider regarding the present study. Firstly, the measure was

developed on a relatively small cohort of individuals, of limited age range, living in PWS-designed

group homes. However, similar results on the FRPQ were obtained for a cohort of individuals

living in the community, suggesting that the measure has wider application. Nevertheless, the

utility of the FRPQ for assessing food-related problems in younger children and older adults with

PWS is unknown. The finding that individuals recruited via the Prader-Willi Syndrome Association

(PWSA,UK) and living in the community were more preoccupied with food than those resident in

PWS-designed group homes is interesting and may reflect a difference in environment; access to

food is strictly controlled in the PWS-designed group homes and food is not physically present

except at meal times. Also, a daily activity schedule is in place for all individuals residing in this

specialist facility. Consequently, all responsibility for food issues have been removed from

individuals, thus preoccupation with food may be hypothesised to be lower. Conversely, the

environmental setting of individuals with PWS residing in the community was not ascertained.

Nevertheless, it is likely that food may be more accessible for these individuals, to be more of a

predominant feature in the lives of those around them and less likely to be under such strict control.

Finally, some items on the measure that require a verbal response by an individual with PWS, allow

the respondent to indicate ‘does not apply’ and this might lower the score. In the samples employed

in this study this occurred very infrequently. However, it should be noted that the data presented

only apply to participants who were rated as ‘does not apply’ on one or no items.

In conclusion, significant within-syndrome variability in aspects of food-related problems were

highlighted for individuals with PWS as measured on the FRPQ, suggesting that food-related issues

are more problematic for some individuals with PWS than for others (also Sarimski, 1996). The

FRPQ may be useful in clinical practice to assess the relationship between food-related problems

and environmental factors and to assess the impact of degree of intellectual disability and effect of


16

age on food-related issues. The FRPQ may also highlight other behaviours such as obsessive and

compulsive characteristics described in individuals with PWS (Hodapp & Dykens, 1995; Stein et

al., 1994). Therefore, a potential clinical use of the FRPQ is to aid in the implementation of

interventions and to evaluate treatment efficacy. Finally, the measure may be adopted by services to

highlight an individual's specific food-related needs and to facilitate appropriate support. In this

way, the stigma often attributed to individuals with PWS and food-related difficulties (Levine,

1995) may begin to be challenged.


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22

Table 1. Description of the Food-Related Problems Questionnaire (FRPQ) subscales,

operational definitions, item inclusion and maximum possible scores

Subscale Operational Definition Maximum

Possible score

Preoccupation Hypervigilant with regard to 18

with food. Excessive reference (by

speech) to food. (eg. How often

does the person talk about food?)

Impairment of Any indication that the person 30

satiety is not satiated and that this is

demonstrated in an appropriate

way. (e.g. Does the person ever

describe 'feeling full'?)

Composite Inappropriate behaviour with 48

negative regard to accessing and storing

behaviour food. Evidence of the person

responding in an inappropriate

way when access to food is

reduced or evidence for external

control being required.

Table 1. continued

Subscale Operational Definition Item number Maximum

Possible score

In particular, evidence that the

person:


23

a) takes food and/or stores food 2, 4, 8 18

inappropriately (eg. Does the

person ever hide or hoard food?)

b) eats inedible items 12, 15 12

(eg. Does the person ever eat

non-edible items (eg. dog food,

leaves)?)

c) responds in an inappropriate 3, 7, 14 18

way when food is not available,

or when access to food is

restricted (eg. Is the person ever

able to accept an explanation given

to them if a meal is delayed?)

Table 2. Inter-rater and Test-retest Reliability Levels for Subscales and Total score of the

Food-Related Problems Questionnaire

Subscales Inter-rater Na Test-retest N

a

and total score reliability reliability


24

Principle subscales

Preoccupation with food .67 35 .70 33

Impairment of satiety .71 30 .74 22

Composite negative

behaviour .82 28 .85 27

Composite negative

behaviour subcategories

Takes/stores food .89 34 .92 32

Eats inedible items .75 30 .71 28

Inappropriate response .56 33 .64 32

Food-Related Problems

Questionnaire total score .86 27 .86 20

a Subscale scores cannot be calculated if there are missing data. Consequently N varies.

Ass

essi

ng food rel

ated p

roble

ms

25

Table 3. A comparison of individuals with PWS and individuals with intellectual disabilities

residing within a community-based group home setting

Pra

der

-Willi syndro

me

C

om

par

ison G

roup

Subsc

ales

and

N

a M

ean

SD

R

ange

N

Mea

n

SD

R

ange

t

sig

tota

l sc

ore

Principal subscales

Pre

occ

upation

with food

23

8.1

0

2.8

0

4 - 1

5

12

3.8

3

2.4

4

0 - 8

4.5

1

< . 0

01

Impai

rmen

t of sa

tiet

y

19

21.9

3.1

8

15 - 2

6

12

13.2

5

5.8

8

5 - 2

6

4.6

8

< . 0

01

Com

posi

te

neg

ativ

e

beh

avio

ur

17

18.8

8

7.9

2

7 - 4

0

12

6.0

8

4.0

3

0 - 1

4

5.1

3

< . 0

01

Composite negative


Tak

es/sto

res

food

22

11.9

5

3.3

6

4 - 1

8

12

2.5

2.3

9

0 - 6

8.6

1

< . 0

01

Eat

s in

edib

le

item

s

18

1.7

8

3.2

5

0 - 1

2

12

.17

0.5

8

0 - 2

2.0

6

< .05

Inap

pro

priat

e

resp

onse

22

6.4

5

3.9

7

1 - 1

4

12

3.4

2

3.5

3

0 - 1

1

2.2

1

< .05

FRPQ

total score

17

48.4

1

12.0

3

27 - 2

9

12

23.1

7

9.6

4

5 - 3

9

6.0

2

< . 0

01

a Subsc

ale

score

s ca

nnot be

calc

ula

ted for so

me

par

tici

pants. C

onse

quen

tly N

var

ies.

Table 4. A comparison of individuals with PWS recruited via two sources

Ass

essi

ng food rel

ated p

roble

ms

26

Pra

der

-Willi syndro

me

: PW

SA

(U

K)

Pra

der

-Willi syndro

me:

gro

up h

om

e

Sub-s

cale

s and

Na

SD

R

ange

M

ean

N

a

SD

R

ange

M

ean

t

sig

tota

l sc

ore

Principal subscales

Pre

occ

upation

with food

56

3.9

6

2 - 1

8

10.6

3

23

2.8

4 - 1

5

8.1

2.7

5

< .01

Impai

rmen

t of

satiet

y

54

5.3

2

11 - 3

0

19.9

1

19

3.1

8

15 - 2

6

21.9

1.9

3

ns

Com

posi

te

neg

ativ

e

beh

avio

ur

53

9.1

4

1 -43

19.3

8

17

7.9

2

7 - 4

0

18.8

8

0.2

ns

Composite negative


Tak

es/sto

res

food

57

5.1

7

0 -18

9.8

8

22

3.3

6

4 - 1

8

11.9

5

2.1

0

< .05

Eat

s in

edib

le

item

s

56

.6

3

0 - 1

1

1.7

9

18

3.2

5

0 - 1

2

1.7

8

0.0

1

ns

Inap

pro

priate

resp

onse

55

3.7

5

0 - 1

8

7.8

2

22

3.9

7

1 - 1

4

6.4

5

1.4

2

ns

FRPQ Questionnaire

total score

52

15.8

7

19 –

87

50.1

3

17

12.0

3

27 –

79

48.4

1

0.4

1

ns

a Subsc

ale

score

s ca

nnot be

calc

ula

ted for so

me

par

tici

pants. C

onse

quen

tly N

var

ies.


27

Appendix. Items from the Food-Related Problems Questionnaire. (Each rated on a seven point

Likert scale: Never to Always)

1. How often does the person compare the size or content of their meal with others? (P)

2. If given the opportunity, how often would the person ‘help themselves’ to food which they

should not have? (N, TS)

3. Is the person ever able to accept an explanation given to them if a meal is delayed? (N, IR)

4. Does the person ever hide or hoard food? (N, TS)

5. How often does the person talk about food? (P)

6. If the person was denied food, how often would they respond negatively? (N, IR)

7. Is it necessary to lock food away to stop the person from taking food? (N, TS)

8. After an normal size meal, how often will the person say they still feel hungry? (S)

9. If the person was tired, ill or upset, how often would this result in them going without food? (S)

10. If it was available, would the person eat food not suitable for consumption (eg. frozen food,

scraps from dustbins)? (N, EI)

11. If a meal includes an item of food the person does not like or is not expecting, how often would

this result in behavioural difficulties? (N, IR)

12. Does the person ever eat non-edible items (e.g. dog food, leaves)? (N, EI)

13. How frequently will the person share food with others? (S)

14. Does the person ever describe ‘feeling full’? (S)

15. Does the person ever associate people and/or places with specific food items or occasions

involving food? (P)

16. If given the opportunity, does the person ever eat more than a standard sized meal? (S)

Legend for subscales: P = preoccupation with food, S = Impairment of satiety, N = Composite

negative behaviour; N, TS = Negative behaviour, takes and stores food; N, EI = Negative

behaviour, eats inedibles.

Documents

The assessment of food related problems in individuals