1. No category

DEVELOPMENTAL MEDICINE & CHILD NEUROLOGY
REVIEW
Quality of life instruments for children and adolescents with
neurodisabilities: how to choose the appropriate instrument
| ELISE DAVIS PHD 1 | GABRIEL M RONEN MD MSC 2 |
PETER ROSENBAUM MD 2 | MICHAEL LIVINGSTON BASC 3 | SAROJ SAIGAL MD 2
ELIZABETH WATERS
MPH DPHIL
1
1 McCaughey Centre, VicHealth Centre for the Promotion of Mental Health and Community Wellbeing, School of Population Health, University of Melbourne,
Melbourne Australia. 2 Department of Pediatrics, Faculty of Health Sciences, McMaster University, Hamilton, Ontario, Canada. 3 University of Western Ontario,
Canada.
Correspondence to Dr Elise Davis, Senior Research Fellow, McCaughey Centre: VicHealth Centre for the Promotion of Mental Health and Community Wellbeing, 207
Bouverie Street, University of Melbourne, Victoria 3010, Australia. E-mail: [email protected]
ABBREVIATIONS
CHQ
HRQoL
PedsQL
QoL
Child Health Questionnaire
Health-related quality of life
Pediatric Quality of Life Inventory
Quality of life
AIM There are many misconceptions about what constitutes ‘quality of life’
(QoL). It is often difficult for researchers and clinicians to determine which instruments will be most appropriate to their purpose. The aim of the current paper is
to describe QoL instruments for children and adolescents with neurodisabilities
against criteria that we think are important when choosing or developing a QoL
instrument.
METHOD QoL instruments for children and adolescents with neurodisabilities
were reviewed and described based on their purpose, conceptual focus, origin
of domains and items, opportunity for self report, clarity (lack of ambiguity),
potential threat to self-esteem, cognitive or emotional burden, number of items
and time to complete, and psychometric properties.
RESULTS Several generic and condition-specific instruments were identified for
administration to children and adolescents with neurodisabilities – cerebral
palsy, epilepsy and spina bifida, and hydrocephalus. Many have parent-proxy
and self-report versions and adequate reliability and validity. However, they
were often developed with minimal involvement from families, focus on functioning rather than well-being, and have items that may produce emotional
upset.
INTERPRETATION As well as ensuring that a QoL instrument has sound psychometric properties, researchers and clinicians should understand how an instrument’s theoretical focus will have influenced domains, items, and scoring.
The concept of ‘good health’ now embraces subjective
well-being and quality of life (QoL), not just absence of
disease. This is a more positive approach consistent with
the World Health Organization’s definition of health as ‘a
state of complete physical, mental, and social well-being
and not merely the absence of disease or infirmity’. Traditional biomedical outcome measures, such as survival or
improvement of symptoms, do not capture all the ways in
which a person may be affected by illness or treatment.
The inclusion of more holistic outcomes such as QoL and
ª The Authors. Journal compilation ª Mac Keith Press 2009
660 DOI: 10.1111/j.1469-8749.2009.03324.x
health-related quality of life (HRQoL) is attracting interest. However, it is often difficult for researchers and clinicians to choose an appropriate instrument.
DEFINING QoL
QoL is an evolving theoretical construct which is variously
defined for children, adolescents, and adults. A generally
accepted definition is that QoL is the ‘individual’s perceptions of their position in life in the context of the culture
and value systems in which they live, and in relation to
their goals, expectations, and concerns’.1 A useful operational definition of QoL is ‘an overall assessment of wellbeing across various domains’.2 For children, QoL
includes, but is not limited to, the child’s perception of
their social, physical, and emotional well-being, and as
such must be sensitive to the changes that occur throughout development3. HRQoL is considered to be a subdomain of the more global construct of QoL which
includes health-related domains of life.4,5
MEASURING QoL
Research studies which measure QoL often do not define
what QoL means or justify the choice and content of the
measure(s) used.6 QoL measures should be viewed as indices of relatively unrelated items and domains. Unlike single-trait scales such as anxiety, the measured variables in
each QoL instrument define the QoL construct of that
particular measure rather than being defined by it.7 There
may be no normal range or standard mean.6 Therefore, clinicians may not know how to select the most appropriate
instrument, or how to interpret scores and integrate them
into clinical practice.8,9
There will always be gaps between what we want to
understand and our efforts to quantify it and this is especially true for QoL.10 It is often difficult to decide which
domains to include in a QoL measure. Increasingly, it is
recognized that children and parents should be consulted
about the important domains of life.2
GENERIC AND CONDITION-SPECIFIC QoL
INSTRUMENTS
Domains of QoL in adult instruments include health,
material well-being, safety, community, productivity, emotional well-being, family, and friends.11 These domains
cannot be assumed to be generalizable to children and adolescents. A recent review of QoL instruments for children
and adolescents reported that the most common domains
of QoL refer to emotions, social interactions, medical
issues ⁄ treatment, cognition, activities, school, family, independence ⁄ autonomy, pain, behavior, future, leisure, and
body image.12
There are two broad types of instrument for assessment
of QoL ‘generic’ and ‘condition-specific’. Generic instruments address a comprehensive array of domains of wellbeing, and have the advantage that the data acquired can
be compared across demographic or clinical populations. A
potential limitation is that they might lack the sensitivity to
detect subtle aspects of specific conditions or disorders in a
way that provides meaningful information to patients and
professionals, although the empirical evidence in this
regard is contradictory. Condition-specific instruments
assess characteristics of a particular condition. As such,
they are generally seen to be more relevant and sensitive to
the nuances of that particular condition.
The domains included in QoL instruments will differ
between generic and condition-specific instruments. For
example, based on a qualitative study of children with cerebral palsy (CP) and their parents, the following domains
were considered to be important to the QoL of children
with CP: social well-being and acceptance, feelings about
functioning, participation and physical health, emotional
well-being, access to services, pain and impact of disability,
and family health.14 While some of these domains overlap
with common generic instruments (social well-being, emotional well-being, family health), others are specific to children with CP (e.g. pain and impact of disability,
functioning). For children with epilepsy, condition-specific
issues include disclosure ⁄ concealment of their epilepsy and
the quest for normality.15
CHARACTERISTICS OF QoL INSTRUMENTS
Essential characteristics of a QoL instrument are outlined
in Table I and discussed below. The aim of this paper is
to describe and analyze QoL instruments for children
and adolescents with neurodisabilities against these
characteristics.
Original purpose of instrument
An instrument used to measure QoL may not have been
designed for that purpose. For example, in studies of children with CP, the Pediatric Outcomes Data Collections
Instrument (PODCI),16 Child Health Questionnaire
(CHQ),17 and Lifestyle Assessment Questionnaire18 have
been used to measure QoL but the PODCI is designed to
measure functional status, the CHQ to measure functional
health and well-being, and the Lifestyle Assessment Questionnaire to measure impact of disability. In studies of
QoL in childhood epilepsy, the Impact of Pediatric Epilepsy on the Family Scale (IPES),19 Hague Restrictions in
Childhood Epilepsy Scale (HARCES),20 and Impact of
Table I: Characteristics of a quality of life instrument
Characteristics
Original purpose of instrument
Actual focus of instrument
Origin of domains and items
Opportunity for self-report
Clarity of items, using children’s own phrases
Threat of negative wording to self-esteem
Number of items and time to complete
Psychometric properties
QoL Instruments for Children and Adolescents with Neurodisabilities Elizabeth Waters et al. 661
Childhood Illness Scale21 have been used but none were
designed to measure QoL.
Actual focus of instrument
An instrument should focus on the personal well-being of
an individual, or their feelings and perceptions about life.
However, many so-called ‘QoL’ or ‘HRQoL’ instruments
focus on functioning (what the person can do) rather than
well-being. For example, the Pediatric Quality of Life
Inventory–CP module (PedsQL–CP module) assesses
whether children have difficulty moving one or both of
their legs, difficulty using scissors, and difficulty brushing
their teeth,22 and the CHQ measures physical functioning
by assessing a child’s limitations in terms of activities such
as playing soccer and riding a bike.17 While functional status and impairment may have an impact on QoL they are
not synonymous with it;6 and a meta-analysis of adult studies measuring both found them to be distinct concepts.23 It
is not possible to estimate a patient’s distress by accumulating their range of problems. Therefore, QoL measures are
needed to provide an evaluation that is separate from the
biomedical health state.24 Questionnaires that aggregate
impairments with QoL to a single score should be avoided.
QoL assessment shows that similar medical conditions
may affect individuals in different ways.25 People with significant health problems can be highly satisfied with some
aspects of their lives (the so-called ‘disability paradox’).26
Recent studies of children with CP, show that functioning
is only weakly related to domains of QoL.27
Origin of domains and items
Until recently, instruments have measured domains that
were decided a priori by professional ‘experts’ (researchers
and clinicians); however, there is increasing recognition
that families and children should be consulted.2,28,29 Qualitative research is well suited to this29 and instrument developers should report in detail the methods they use.
Instruments are more likely to have content validity if
items are derived from a sample of the population in which
the instrument is to be used.30 Children identify more
items than health professionals or their own parents, and
contribute significantly to the wording of items.31
Opportunity for self-report
In the adult literature self-report questionnaires are the
primary method of assessing QoL whereas childhood literature has suggested that parents may be better able than
the child to rate their child’s QoL because of their child’s
cognitive immaturity, limited social experience, and continued dependency.32 However this view is changing, especially for children aged 8 years and over. New instruments
have child self-report versions. The instruments usually
662 Developmental Medicine & Child Neurology 2009, 51; 660–669
start at about age 8 years32 because test–retest reliability
was poor in children with epilepsy aged 6 to 7 years, while
those 8 years and older showed acceptable results.15 However, where child ⁄ adolescent self-reports cannot be collected because of age, disability, or cognitive impairment,
parent proxy measures are valuable. A systematic review of
14 studies assessing the relationship between parent-proxy
and child self-reported QoL demonstrated that the level of
agreement depended on the domain.32 Generally there was
good agreement (correlations >0.5) between parents and
children for domains reflecting physical activity, functioning, and symptoms but poorer agreement (correlations
<0.30) for domains which reflected social or emotional
domains.
Threat of negative wording to self-esteem
Items may threaten self-esteem by making assumptions
about an illness. For example, the DISABKIDS-CP Module includes items such as ‘Does it bother you that you
have to explain to others what you can and can’t do?’ ‘Is it
frustrating to be unable to keep up with other children?’
‘Do people think that you are not as clever as you are?’
Although these items may have sound psychometric properties, there may be ethical implications to including such
questions.
Number of items and time to complete
The number of items and time required to complete a
QoL instrument are important considerations, particularly
for children. We think that completion of a measure
should not take longer than 10 to 20 minutes.
Psychometric properties
Instruments should demonstrate adequate test–retest reliability, validity, and factor structure. If designed to evaluate
interventions, they should also demonstrate evidence of
sensitivity to change.
Cronbach’s coefficient alpha (a) is a useful measure for
internal consistency in scales that tap a single dimension
construct but not necessarily in multidimensional measures
such as QoL where the items may not correlate closely
with each other. Because the a is sensitive to the length of
the instrument, a long scale may have a high value even
where there is heterogeneity. Therefore, an optimal value
of the a to measure the internal consistency of a measure is
a necessary but not a sufficient index of reliability; and values over 0.9 are likely to indicate redundancy.33,34 Good
test–retest reliability confirms that the scale is stable over
time and values of the intraclass coefficient should be >0.6.
Construct validity assesses an instrument in the absence of
a criterion standard and refers to predictions regarding
how the instrument should behave based on hypotheses.
The process is usually established over a number of studies, tapping various aspects of the hypothetical construct.
Factor analysis is important for developing multiconstruct measures because it may reveal patterns of interrelationships among variables not otherwise apparent,
identify independent domains and redundant domains,
reduce the number of items and retain only those items
that correlate primarily with a single domain.
RESULTS
Generic QoL instruments for children and adolescents
with neurodisabilities
Several generic instruments were identified including the
CHQ, PedsQL, and KIDSCREEN. Each is described
briefly against the features laid out in Figure 1.
Child Health Questionnaire
The CHQ is a proxy-completed generic instrument
designed to measure functional health status, well-being,
and health outcomes of children aged 0 to 18 years.35 Its
domains are behavior, bodily pain, general health, mental
health, parent impact-emotional, physical functioning, parent impact-time, role-emotional ⁄ behavioral, role-physical,
and self-esteem; there are also physical and psychosocial
summary scores.35 The items were developed by experts
and adapted from a variety of existing instruments. The
CHQ only has a self-report version for adolescents and it
is long. Although the CHQ is reliable and valid for children with CP, we have not found studies which examined
its sensitivity to change.
A recent study compared the psychometric properties
of the CHQ with the CP QoL Questionnaire for
METHOD
A systematic review was conducted to identify pediatric
condition-specific and generic QoL and HRQoL instruments for children and adolescents with neurodisabilities.
It employed a search strategy of the published literature on
the Medline and PsychLit electronic databases to identify
QoL instruments published between 1990 and 2007, using
the terms ‘children, adolescent, QoL (encompassing
HRQoL), neurodisabilities, CP, spina bifida, and epilepsy’.
A total of 474 abstracts were reviewed to identify
QoL ⁄ HRQoL instruments, and further information was
then obtained on each instrument. The instruments were
reviewed and mapped to the characteristics set out in
Table I.
Health or
functioning
Low
involvement
of families
Original purpose of instrument
CHQ
KIDSCREEN
PedsQL
Origin of items
PedsQL
CHQ
KIDSCREEN
Quality of life
High
involvement
of families
Actual focus of the instrument
Functioning
No
opportunity
for self-report
Negative
wording
Large number
of items
Poor or not
demonstrated
PedsQL
CHQ
KIDSCREEN
Opportunity for self-report
CHQ (13+)
KIDSCREEN
PedsQL (5+)
Potential threat to self-esteem
PedsQL
KIDSCREEN
CHQ
Length
CHQ (self-report
87 items)
KIDSCREEN (10,27,52)
PedsQL
CHQ parent
Psychometric properties
KIDSCREEN
PedsQL
CHQ
Well-being
Self-report
version
available
Positive
wording
Small number
of items
Excellent and
demonstrated
adequately
Figure 1: Features of generic quality of life instruments for children and adolescents to with neurodisabilities. CHQ, Child Health Questionnaire;
PedsQL, Pediatric Quality of Life Inventory.
QoL Instruments for Children and Adolescents with Neurodisabilities Elizabeth Waters et al. 663
Children (CP QoL-Child) and KIDSCREEN-10 for
children with CP; it suggests that the CHQ is not the
most appropriate instrument available to measure the
QoL of children with CP.36 The internal consistency of
the CHQ ranged from 0.18 to 0.96 across different
domains. Correlations between CHQ and KIDSCREEN
were good (r=0.25–0.53) but correlations between CP
QoL-Child and CHQ ranged from 0.01 to 0.5 with similar domains correlating moderately.36 Finally, the CP
QoL-Child and KIDSCREEN-10 outperformed the
CHQ in terms of floor and ceiling effects with floor
effects observed for all domains of the CHQ except general health (5–25%), and ceiling effects for all domains of
the CHQ (2.9–60.8%).36
Pediatric Quality of Life Inventory
The PedsQL is a measure of HRQoL for children and
adolescents aged 2 to 18 years. It assesses physical, emotional, social, and school functioning. The four factors correlated highly from 0.75 to 0.88 suggesting that they might
tap into related issues of emotional functioning.37 The
PedsQL is brief and has a child self-report version; however the items focus on functioning and what the child can
do, as well as on how much difficulty a child has doing
something. If a child does have a lot of difficulty, the items
might threaten self-esteem. The PedsQL Generic Core
Scale has adequate psychometric properties with internal
consistency ranging from 0.70 to 0.89 for proxy-report and
0.54 to 0.86 for self-report.22 Correlations between the
Generic Core Scale and CP module (see below) ranged
from weak (0.1–0.2) to moderate (0.40–0.43) to significant
(0.5–0.8).22
KIDSCREEN
KIDSCREEN is a self- and proxy-completed generic
instrument, created with children’s input, that is designed
to measure the QoL of healthy and chronically ill children
and adolescents aged 8 to 18 years. Its domains include
physical well-being, psychological well-being, social support and peers, and financial resources. The inter-subscale
correlation ranges from 0.1 to 0.62 in keeping with an
index of relatively independent domains. As indicated in
Figure 1, KIDSCREEN is the only generic instrument
that has high involvement of children and families in its
development, assesses well-being, has a child self-report
version, no apparent threat to self-esteem, a limited number of items, and good psychometric properties. In European normative samples, KIDSCREEN-10 has sound
psychometric properties with good internal consistency
(0.82) and test–retest reliability (r=0.73),38 confirmed by a
recent Australian study which also reported good internal
consistency (0.86) and reliability with correlations between
664 Developmental Medicine & Child Neurology 2009, 51; 660–669
KIDSCREEN-10 and CP QoL-Child ranging from 0.30
to 0.54.36
CONDITION-SPECIFIC QOL INSTRUMENTS FOR
CHILDREN AND ADOLESCENTS WITH
NEURODISABILITIES
Cerebral palsy (see Fig. 2)
The following four condition-specific QoL ⁄ HRQoL
instruments were identified: the CP QoL-Child, The
Caregiver Priorities and Child Health Index of Life with
Disabilities (CPCHILD), the PedsQL-CP module, and
DISABKIDS.
CP QoL Questionnaire for Children
The CP QoL-Child is designed to measure the QoL of
children with CP aged 4 to 12 years. Its seven domains are
social well-being and acceptance, functioning, participation
and physical health, emotional well-being, access to
services (parent-proxy only), pain and feelings about disability, and family health (parent-proxy only).39 The CP
QoL-Child items focus on assessment of well-being and
present no threat to self-esteem. The parent-proxy version
is psychometrically sound while early results of the child
self-report version suggest it has good psychometric properties. For parent-proxy, the two week test–retest reliability
ranged from r=0.76 to 0.89 and internal consistency ranged
from 0.74 to 0.92. The questionnaire was moderately correlated with the CHQ and KIDSCREEN, supporting the
validity of the CP QoL-Child parent-proxy version.39
Child Health Index of Life with Disabilities
The CPCHILD40 is a Canadian condition-specific health
functioning instrument for children and adolescents with
severe CP. It focuses on measuring caregivers’ perspectives
of the activity limitations, health status, well-being, and
ease of care. It consists of 36 items in six sections: personal
care; positioning, transfers and mobility; communication
and social interaction; comfort, emotions and behavior;
health; and overall QoL. Items are rated on degree of difficulty (‘no problem’ to ‘impossible’) and level of assistance
(‘independent’ to ‘total assistance’). Early analysis of the
CPCHILD suggests that it has sound psychometric properties with 2 week test-retest ranged from r=0.88 to 0.96.40
Pediatric Quality of Life Inventory–CP module
The PedsQL-CP module,22 is a condition-specific
HRQoL questionnaire for children and adolescents with
CP. The 35-item CP module yields the following seven
scales: daily activities, school activities, movement and balance, pain and hurt, fatigue, eating activities, and speech
and communication. The questionnaire is designed for
children aged 2 to 18 years. According to Varni et al.22 the
Health or
functioning
Low
involvement
of families
Original purpose of instrument
CP QoL-Child
PedsQL-CP
DISABKIDS-CP
CPCHILD
Origin of items
CPCHILD
PedsQL-CP
DISABKIDS-CP
CP QoL-Child
Quality of life
High
involvement
of families
Actual focus of instrument
Functioning
No
opportunity
for self-report
Negative
wording
Large number
of items
Poor or not
demonstrated
PedsQL-CP
CPCHILD
DISABKIDS-CP
CP QoL-Child
Opportunity for self-report
CPCHILD
CP QoL-Child
PedsQL-CP
DISABKIDS-CP
Potential threat to self-esteem
PedsQL-CP
DISABKIDS-CP
CPCHILD
DISABKIDS-CP
CPCHILD
CP QoL-Child
CP QoL-Child
Length
Psychometric properties
CPCHILD
CP QoL-Child
DISABKIDS-CP
PedsQL-CP
PedsQL-CP
Well-being
Self-report
version
available
Positive
wording
Small number
of items
Excellent and
demonstrated
adequately
Figure 2: Condition-specific quality of life instruments for children and adolescents with neurodisabilities. CPCHILD, The Caregiver Priorities and
Child Health Index of Life with Disabilities; CP Qol-Child, CP QoL Questionnaire for Children; PedsQl, Pediatric Quality of Life Inventory.
Module has adequate psychometric properties with internal consistency ranging from 0.88 to 0.96 for proxy-report
and 0.63 to 0.93 for self report; (fatigue 0.63, speech and
communication 0.95, and daily activities 0.96 ⁄ 0.93). Correlations between the CP module and Generic Core Scale
were varied ranging from weak (0.14–0.23), moderate
(0.40–0.43), to significant (0.52–0.84).
DISABKIDS – CP Module
DISABKIDS is designed to measure HRQoL and includes
a generic module, a chronic generic module, and a condition-specific module. The generic module comes from the
KIDSCREEN and is suitable for all children. The chronic
generic module is suitable for use with children and adolescents who suffer from any chronic health-related condition. A condition-specific module has been developed for
the chronic conditions studied in the DISABKIDS Project,
which include CP.41
Childhood epilepsy (see Fig. 3)
The quality of life measure for children with epilepsy42
This parent-proxy reported instrument was developed for
children with refractory epilepsy, aged 4 to 18 years with
average intellectual abilities, and is based on the responses
of 68 parents. The items are derived from a survey questionnaire, review of the literature, and related measures.
There are 16 domains with 1 to 16 items per domain and a
total of 79 items. The high internal consistency in six subscales suggests redundancy of items. Correlation between
subscales ranges from 0.07 to 0.84. Items focus on psychological-emotional health and social issues. The sample size
precluded the use of factor analysis and the psychometric
properties lack test–retest analysis. The acceptable internal
consistency of the measure is limited to the characteristics
of the sample tested, and may be only marginal for other
populations.
The quality of life inventory for adolescents with epilepsy43
This is a self-report instrument for adolescents with epilepsy. The measure has 48 items distributed in eight subscales based on reviews of literature, existing measures,
focus groups of adolescents with epilepsy, and professional
opinion. A conceptual framework is not present. Factor
analysis of the 197 completed questionnaires was poorly
reported. The majority of the items and subscales seem to
portray emotional functioning. Internal consistency points
QoL Instruments for Children and Adolescents with Neurodisabilities Elizabeth Waters et al. 665
Health or
functioning
Low
involvement
of families
Original purpose of instrument
QOLCE
QVCE-50
CHEQOL-25
QOLIE-AD-48
Origin of items
QOLCE
QVCE-50
QOLIE-AD-48
Quality of life
CHEQOL-25
High
involvement
of families
CHEQOL-25
Well-being
CHEQOL-25
QOLIE-AD-48
Self-report
version
available
Actual focus of instrument
Functioning
No
opportunity
for self-report
Negative
wording
QOLCE
QVCE-50
QOLIEAD48
QOLIE-AD-48
Opportunity for self-report
QOLCE
QVCE-50
Potential threat to self-esteem
QOLIE-AD-48
QOLCE
QVCE-50
CHEQOL-25
Positive
wording
CHEQOL-25
Small number
of items
Length
Large number
of items
QOLCE
Poor or not
demonstrated
QOLCE
QVCE-50
QOLIE-AD-48
Psychometric properties
QVCE-50
QOLIE-AD-48
CHEQOL-25
Excellent and
demonstrated
adequately
Figure 3: Condition-specific quality of life instruments for children with epilepsy. QOLCE, Quality of Life for Children with Epilepsy; QUCE, Brazillian
quality of life questionnaire for children with epilepsy; CHEQCH-25, Health related quality of life for childhood epilepsy; QOLIE-AD-LO8, quality of life
inventory for adults.
to redundancy of items in two subscales. Regression analysis for the ‘overall HRQoL’ identified the age of the adolescent, seizure severity, neurotoxicity of antiepileptic
drugs, and socio-economic status as the main risk factors43
HRQoL questionnaire for Brazilian children with
epilepsy44
This is a caregiver-reported instrument in Portuguese.
The items were pooled from other measures, the literature,
and the authors’ personal experience. Although the wording was chosen to prevent negative feelings many items
read negatively in translation. The 50 items and four
domains cover physical health, psychological health, social
and family relationships, and cognitive educational issues,
suggesting a mix of objective functional and emotional
health with subjective perceptions.
Impact of pediatric epilepsy on the family19
This 11-item parent response measure intends to evaluate
the impact of epilepsy on the family’s and child’s life. The
items were generated from the authors’ clinical experience
and review of the literature. A theoretical concept is absent,
666 Developmental Medicine & Child Neurology 2009, 51; 660–669
with no a priori explanation why these 11 items were most
important. Factor analysis identified three factors, namely
participation, interpersonal relationships, and family
dynamics. The high values of internal consistency suggest
that the items tap into a single factor.34
HRQoL for childhood epilepsy
The work of Ronen et al.15,28,29 on the measurement
of HRQoL in children and youth with epilepsy captures the experiential aspects of childhood epilepsy
from the youths’ and parents’ perspective. These
related measures have a conceptual basis that de facto
provides a more specific definition of HRQoL in childhood epilepsy than any previous definitions.45 The conceptual model was generated by interviewing children
and their parents separately, using focus groups.29
Their perception of QoL while living with epilepsy
was derived from a textual analysis of their narratives.28
The findings informed the preliminary HRQoL instrument. The measure was administered to 381 children
with epilepsy and their parents across Canada and the
data were submitted to factor analysis. This generated
selected and put into question form scaled with a 5-point
Likert scale. The following ten domains were identified:
social, emotional, intellectual, financial, medical, independence, environmental, physical functioning, recreation,
and vocational, a mixture of well-being and functioning
domains. The parents of the 5- to 12-year olds were particularly concerned about the emotional needs of the child
and family. The 13- to 20-year-old adolescents were particularly concerned about opportunities for independence
and the general public’s perceptions of them. Parents and
children were most concerned about the development of
social and self-care skills.49
the conceptual domains compromising HRQoL and
became the subscales used in its measurement.15
This model comes closer than many others to
what youth mean by HRQoL, as the domains were not
generated by professionals.46,47 The measure has the
following five domains: (1) interpersonal ⁄ social consequences, (2) worries and concerns mostly in daily life
experiences, (3) intrapersonal ⁄ emotional issues, (4) secrecy
and concealment of epilepsy, and (5) quest for normality.
The correlation between the subscales ranged from 0.26
to 0.52. Factor analysis of the Chinese translation of
this measure in Hong Kong identified the same factor
structure, providing additional cross-cultural validity to
the conceptual model and the instrument.48 The measure’s responsiveness has yet to be tested in longitudinal
studies.
Hydrocephalus Outcome Questionnaire50 (HOQ) and
Parental Concerns Questionnaire51
The HOQ instrument for children with hydrocephalus is
intended to measures the objective functional status of the
child. Factor analysis was not performed and the psychometric properties suggest redundancy of items. The related
Parental Concerns Questionnaire originated from focus
groups with the parents of children with hydrocephalus
during the HOQ development. The nine items with the
highest severity and importance scores were included. The
Spina-bifida and hydrocephalus (see Fig. 4)
Parkin et al.49 generated items by peer interviews with
health professionals and in-depth interviews with children
with spina bifida and their parents. Approximately 600
items were ranked by the children and parents according
to their importance, and the highest ranked 50 items were
Health or
functioning
Original purpose of instrument
HOQ
HRQL-SB
Quality of life
HRQL-SB
High
involvement
of families
Origin of items
Low
involvement
of families
HOQ
Actual focus of the instrument
Functioning
HOQ
No
opportunity
for self-report
HOQ
Negative
wording
Opportunity for self-report
HRQL-SB
Potential threat to self-esteem
HOQ
HRQL-SB
Length
Large number
of items
Poor or not
demonstrated
Well-being
HRQL-SB
HOQ
HRQL-SB
Psychometric properties
HOQ
HRQL-SB
Self-report
version
available
Positive
wording
Small number
of items
Excellent and
demonstrated
adequately
Figure 4: Condition specific quality of life instruments for children with spina bifida and hydrocephalus. HOQ, Hydrocephalus Outcome Questionnaire; HRQL-SB, health related quality of life for children with spina bifida.
QoL Instruments for Children and Adolescents with Neurodisabilities Elizabeth Waters et al. 667
internal consistency measured 0.89, test–retest reliability
0.86, and interrater reliability 0.67 between mothers and
fathers. Although this scale taps into subjective feelings of
parents it is not intended to measure QoL of children with
hydrocephalus.
DISCUSSION
The measurement of QoL of children and adolescents with
neurodisabilities has advanced significantly over the last
decade. There are now several generic and condition-specific QoL instruments available. This paper shows these
instruments are often developed with little involvement of
families, focus on functioning rather than well-being, and
have items that are negatively worded.
Researchers and clinicians should be aware of how an
instrument was developed and its theoretical focus as these
will influence the domains, items, and resulting scores.
They should also ensure that an instrument has sound psychometric properties. It is important for researchers and
clinicians to understand the theoretical underpinning and
purpose of instruments.
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