Economic Evaluation of Interventions for Children with Neurodevelopmental Disorders: Opportunities and Challenges
Economic Evaluation of Interventions for Children with Neurodevelopmental Disorders: Opportunities and Challenges
Ramesh Lamsal 0 1
Jennifer D. Zwicker 0 1
0 Faculty of Kinesiology, University of Calgary , Calgary , Canada
1 & Jennifer D. Zwicker
Economic evaluation is a tool used to inform decision makers on the efficiency of comparative healthcare interventions and inform resource allocation decisions. There is a growing need for the use of economic evaluations to assess the value of interventions for children with neurodevelopmental disorders (NDDs), a population that has increasing demands for healthcare services. Unfortunately, few evaluations have been conducted to date, perhaps stemming from challenges in applying existing economic evaluation methodologies in this heterogeneous population. Opportunities exist to innovate methods to address key challenges in conducting economic evaluations of interventions for children with NDDs. In this paper, we discuss important considerations and highlight areas for future work. This includes the paucity of appropriate instruments for measuring outcomes meaningful to children with NDDs and their families, difficulties in the measurement of costs due to service utilization in a wide variety of sectors, complexities in the measurement of caregiver and family effects and considerations in estimating long-term productivity costs. Innovation and application of evaluation approaches in these areas will help inform decisions around whether the resources currently spent on interventions for children with NDDs represent good value for money, or whether greater benefits for children could be generated by spending money in other ways.
Key Points for Decision Makers
School of Public Policy, University of Calgary, 906-8th
Avenue SW, Calgary AB T2P 1H9, Canada
Economic evaluation provides information on costs and
consequences of healthcare interventions to prioritize
interventions that could improve population health [
decision problem addressed by economic evaluation
considers the choice between different types of healthcare
interventions by assessing the value for money, given a
budget constraint. Neurodevelopmental disorders (NDDs)
are a heterogeneous group of conditions with onset in the
developmental period, characterized by impairments in
personal, social, educational or occupational functioning.
Manifesting in early development and ranging from
specific limitations of learning or control of executive
functions to global impairments of social skills and
intelligence, these functional limitations have implications
for the well-being of the child, the family, and society [
When resources are limited, decision makers are
increasingly turning to evidence generated by economic
evaluation to make decisions about resource allocation, but little
evidence exists regarding economic evaluations of NDD
While the number of economic evaluations in child
health grows rapidly [
], few economic evaluations are
specific to NDDs. Beyond the core challenges all
evaluations working with a pediatric population face [
NDDs warrant specific consideration. In this paper, we
highlight some key challenges and opportunities for this
population related to developing outcome measures
meaningful to children with NDD [
], costing service
utilization in different sectors , incorporation of
caregiver and family effects [
] and estimating long-term
productivity costs [
2 Economic Evaluation Methods
2.1 Perspective and Time Horizon
The perspective in an economic evaluation provides a
framework for analysis and determines what costs and
effects to include and how to value them. The healthcare
sector perspective includes formal healthcare costs borne
by third-party payers or paid for out-of-pocket by families.
The Guidelines for the Economic Evaluation of Health
Technologies in Canada (CADTH) recommends reporting
a reference case from a publicly funded healthcare payer
]. It should reflect the costs incurred by
Canadian public payer and health effects for patients and
their informal caregivers.
NDD interventions are complex and often include
nonhealth outcomes such as education performance [
], (social) participation [
], better captured by adopting a societal
perspective. The societal perspective is a broader perspective,
capturing health and non-health costs or effects such as
time costs of children and families in seeking and receiving
care, time costs of informal (unpaid) caregivers,
transportation costs, effects on future productivity and
consumption. The National Institute for Health and Care
Excellence (NICE) recommends a broader perspective
regarding cost, indicating that the cost in a reference case
should use National Health Services and personal social
services perspectives. NICE advises that the outcomes in a
reference case should measure all the direct health effects
relevant to patients and carers [
]. The second panel on
cost-effectiveness in health and medicine in the USA (USA
panel on CEA) recommends reporting the reference case
analysis from a healthcare sector or a societal perspective
For children with NDD, a lifespan time horizon can be
important because the impact of interventions is expected
to manifest in adulthood and throughout their lifespan. The
time horizon should reflect resources consumed and
outcomes experienced over the lifetime of participants as part
of, or as a result of, an intervention. The USA panel on
CEA, CADTH, and NICE recommend adopting a time
horizon long enough to capture all relevant differences in
the future costs and outcomes associated with the
alternatives compared. However, longer time horizons introduce
higher uncertainty because of variation in discount rates
]. When creating long-term and lifetime models to
capture the effects of an intervention, different discount
rates should be considered [
2.2 Measurement of Costs
Costing involves the systematic identification,
measurement, and valuation of resources used in the intervention
and the comparators, and should reflect the opportunity
cost for children with a NDD and their families utilizing
these resources. Costs can be categorized into costs of care,
and productivity costs. Costs of care can include
expenditure on healthcare, therapeutic, behavioral or educational
services, transportation, caregivers and other special needs
services for a child with a NDD. Productivity costs include
a reduction in the ability of either the child with a NDD
(when they become adults), or parent of a child with a
NDD, to sustain paid employment.
Children with NDDs need a range of services during
their lifetime; often extending beyond healthcare services,
utilization occurs in social services, rehabilitation, the
education and criminal justice systems. A systematic
review on the economic consequences of child and
adolescent mental illness in the UK found that only 6% of the
costs fall on the health system, and the majority of costs
were from outside (social services, productivity, education
and the criminal justice system) [
]. Furthermore, the
needs of services for children with NDD diagnosis change
as setting and age change [
]. For instance, a child with
autism spectrum disorder (ASD) may require a home-based
special educator or early intervention therapies in early
], special education during school years [
and employment support or vocational training during the
transition into adulthood [
]. Consequently, compiling
and quantifying service usage in monetary units for an
economic evaluation can be challenging [
adopting a narrower public health-care system perspective
might be an option, failure to incorporate other relevant
sources and settings may bias the results when the majority
of service usage is outside the healthcare system.
Productivity costs are often captured as the loss of value
of gross earnings resulting from the NDD for the child,
parents (or caregivers) and other family members relative
to a comparator [
]. A lack of social skills, adequate
training, appropriate working environment and education,
or appropriate supports [
], means that adolescents with a
NDD have enormous difficulties in getting a job, and
keeping it, as they transition from school to employment.
For example, in Canada, the employment rate of
workingage adults with a developmental disability (22.3%) was less
than one-third of the rate for people without a disability
The impact on productivity for parents and caregivers
can be considered in terms of time spent in formal or
informal labor markets. Primary caregivers of children with
a NDD often must give up work, reduce working hours, or
change jobs to provide support and care. An estimated 85%
of individuals with ASD need some measure of care and
assistance from their parents and families for the duration
of their lives [
]. The employment stability of family
members in the household (including parents and siblings)
is also affected by the health of a child with a NDD [
Mothers of children with disabilities are 3–11% less likely
to work, and the effect (13–15%) is larger if the child is
severely disabled [
When compiling and quantifying service usage in
monetary terms, there are two main challenges. First,
establishing a causal relationship can be difficult in
practice. For example, distinguishing the hours of care provided
by caregivers related to NDD compared to usual care is a
challenge. Second, quantifying productivity for children in
terms of the child’s future earnings is problematic. Persons
with a NDD make less money on average than persons
without a NDD [
]. While not unique to NDD,
incorporating these productivity costs in an economic evaluation
warrants careful consideration. For example, if we use a
human capital approach to estimate the productivity costs,
then costs associated with each day of lost work will be
lower for an individual with NDD than for individuals
without NDD. Given the high productivity costs for
wealthy individuals, the economic evaluation would
prioritize interventions for affluent individuals rather than
interventions more prevalent among those who earn lower
wages. However, failure to incorporate the impacts of early
interventions on productivity in adulthood could
potentially underestimate the effectiveness of the intervention.
2.3 Measurement of Outcomes (Effectiveness)
Measurement of health outcomes in children with NDDs
typically involves assessment of physical, social,
psychological and cognitive functioning. Outcomes should reflect
the experience and well-being of children with NDDs who
are utilizing supports and services. For reference case
analysis, all three guidelines (USA panel on CEA,
CADTH, and NICE) recommend reporting the health
consequences of changes in morbidity or mortality in
quality-adjusted life years (QALYs) [
Deriving a QALY in pediatric populations is a
challenge. In a recent review of pediatric economic evaluations
published between 1980 and 2014, only 24.9% were
costutility analyses with the majority being cost-effectiveness
analyses (63.9%) [
]. To date, very few evaluations of
interventions for children with a NDD have reported
QALYs, due to challenges with measurement. Instruments
used in economic evaluation of interventions for NDD are
summarized in Table 1 (general health profile measures)
and Table 2 (preference-based measures) [
Typically, natural units such as dependency-free life years
] clinical- or disease-specific outcomes [
general health profile measures (Table 1) that are familiar
to clinicians and patients are used to measure consequences
of NDD interventions. A recent cost-effectiveness analysis
of a communication-focused therapy for pre-school
children with ASD highlights challenges with clinical or
disease-specific measures [
]. The primary outcome measure
reflected autism symptom severity, and without the societal
value relative to a unit improvement, it is difficult to
compare interventions even within NDDs.
Many general health profile measures are adapted from
measures developed for adult populations and not designed
for NDDs. Each instrument has different domains, and
adapting to a NDD intervention can be difficult. For
example, the Child Health Questionnaire (CHQ),
KIDSCREEN and Child Health and Illness Profile (CHIP) have a
significant number of items related to social dimensions
such as school, family, and peers, whereas the Pediatric
Quality of Life Inventory (PedsQL) has more items that
focus on physical and emotional functioning (Table 1). A
recent study by Janssens et al looked at these instruments in
the context of NDD and found a lack of evidence on
responsiveness and measurement error, making it difficult
to distinguish meaningful (clinically important) change
]. Of the instruments assessed in this study, the PedsQL
and CHQ were most evaluated in NDD populations, but
findings were not satisfactory. Ultimately, the main
disadvantage of using either a general health profile or
disease-specific measure for economic evaluation is the lack
of standardization into a scale that can elicit a QALY.
Few studies relating to children with a NDD have used
preference-based measures as an outcome measure
(Table 2). There are also differences in the domains
captured in preference-based measures. The reliability and
validity of preference-based instruments in children with
NDD need to be examined. For instance, a study by Tilford
et al [
] comparing preference-based and clinical
Used in children
a This is not a comprehensive list of the general health profile measures, but gives examples of instruments used most commonly in the field
a This is not a comprehensive list of the preference-based HRQoL, but gives examples of instruments most commonly used in the field currently
measures in ASD, found that the Health Utilities Index
(HUI)-3 to be a good measure of effectiveness and should
be included in clinical trials. Other studies are needed to
assess these instruments in other NDDs for their ability to
capture meaningful clinical changes.
Using direct approaches such as standard gamble or time
trade-off for deriving a QALY is another approach, but can
be as problematic for children with NDD as in other
pediatric populations. Children with a NDD are more likely
to experience emotional and behavioral dysregulation,
social exclusion, isolation and poorer academic
performance than their peers who do not have a disability [
This may influence a child’s understanding of health and
well-being, meaning they may not have the capacity to
understand the concept of time in a way that would allow
them to indicate their preference.
If preference-based measures are not feasible, general
health profile measures can be converted into QALYs using
]. This is an emerging opportunity in the field
of NDDs as it allows for adaptation of data collected from
commonly used general health profile measures such as the
KIDSCREEN or PedsQL to estimate a QALY. Algorithms
for mapping general health profile measures into health
utilities have been reported for some conditions [
however, very few algorithms have been created
specifically for children with NDD [
Ideally, outcome measures should reflect a child’s
experience and perception. Due to feasibility, reliability,
and validity issues, proxies such as parents, caregivers and
healthcare professionals are used. Proxy reporters can be
effective for visible signs and symptoms but are less
accurate for subjective measures such as quality of life
(QoL), emotion, and utility. Reporting is impacted by the
proxy’s knowledge, experiences, and expectations [
is particularly important as each NDD has a unique
etiology and wide heterogeneity of symptoms and
co-morbidities such as mental health considerations [
The limitations of QALYs in capturing non-health
outcomes has resulted in some researchers calling for more
comprehensive outcome measures [
‘‘Capability approach’’ has been proposed as one alternative
]. The capability approach is based on the view of
living as a combination of various ‘doings and beings,’
with the QoL to be assessed in terms of the ‘‘capability to
achieve valuable functioning’’ , p31. The essence of
the capability approach is that ‘‘an individual’s well-being
should not be measured according to what they actually do
(that is their function) but what they can do (their
], p850. In this context, the capability approach
offers the potential for a richer set of dimensions in the
evaluation of interventions for children with NDD [
number of capability-based instruments/questionnaires
(Investigating Choice Experiments Capability Measure
[ICECAP], Oxford Capability Instruments [OxCAP], Adult
Social Care Outcome Toolkit [ASCOT], etc.) have been
developed for use in healthcare. However, application of
this approach in economic evaluations of interventions for
children with NDDs requires development and testing of
the capability-based questionnaire/instruments for this
2.4 Caregivers and Family Effects
The notion that children are not ‘isolated individuals,’ but
rather have a social circle of parents, siblings, other
relatives and friends has emerged in the health economic
]. There are two main effects, described as
‘caregiving effects’ and ‘family effects,’ which are
spillover effects. The caregiving effect refers to the impact of a
child’s health on the QoL and economic well-being of a
caregiver, and family effects refer more broadly to the
impact of a child’s health on QoL and economic well-being
of family members, applying to parents, siblings and other
relatives living in the household. The importance of
incorporating spillover effects in economic evaluations of
health interventions has been described [
guidelines (US panel on CEA, CADTH and NICE)
recommend including spillover effects for caregivers in the
reference case analysis [
13, 18, 19
]; however, applications
to specific conditions and treatments remain limited.
An intervention can have positive and negative effects
on the QoL and economic well-being of both the child with
NDD and their caregivers and family members. Parents of
children with NDD report poorer physical and mental
health and experience higher levels of family distress than
parents who are not raising children with NDD [
longitudinal population study looked at the impact on the
maternal and paternal health of having a child with a
disability in the household. After controlling for previous
health status and other sociodemographic characteristics,
the health of mothers declined compared to fathers [
Caregivers of children with NDD experience more health
and psychological problems such as stress, problematic
family functioning, migraine headaches and asthma
compared to caregivers of neurotypical children [
caregivers’ health suffers as the severity of disability and
needs of patient increases [
]. Siblings of children
with a chronic illness may also be impacted, as a
metaanalysis showed fewer peer activities and lowered
developmental cognitive scores compared to siblings without a
chronic illness .
Acknowledging these dynamic, complex and changing
dependency relationships between a child’s health and the
QoL of family members, a number of researchers have
proposed different methods of incorporating family and
caregiver effects into economic evaluation. Basu and
Meltzer developed a theoretical framework based on a
utility function for measuring family spillover effects and
have shown how medical treatment could provide direct
and indirect effects on the welfare of all family members
]. Al-Janabi et al advanced research on health spillovers
by developing a framework, which involves the inclusion
of two multiplier effects: multiplier effects for health
benefits generated and displaced by a new intervention
A few methodological approaches for isolating and
measuring spillover health effects of caregivers and family
members (separately) have been introduced in the
literature. Brouwer et al and Poley et al have used the EQ-5D to
measures the health-related QoL of rheumatoid arthritis
caregivers and parents providing informal care to young
patients with congenital anomalies [
]. They found
that effects of illness were extended to other members of
the family. Similarly, using a modified time trade-off
method, Basu et al evaluated the impact on the QoL of
partners due to a patient experiencing prostate cancer .
The spouse of the patient was asked to trade off his or her
life based on their expected burden if the patient developed
one of the prostate cancer-related health states. Using
standard gamble (SG) methods, Prosser et al asked family
members of Alzheimer/dementia, arthritis, cancer and
depression patients to value the spillover effects [
found that effects of illness extend beyond the individual
patient to caregivers, children, a spouse, and family
members. Spillover effects on caregivers can also be
measured using the CarerQol, a carer-related QoL
]. While numerous methods to incorporate
caregiver and family effects have been suggested in the
literature, there is a lack of standardized methodology, and
more empirical and theoretical work related to NDD is
There is an urgent need for identifying or developing the
most appropriate instruments or methods that take into
consideration the measurement challenges present for
economic evaluations of interventions for children with a
NDD. This paper is the first step to highlighting these
challenges and outlines considerations when conducting an
economic evaluation in this field. Children with NDD
present unique challenges for health-specific outcome
measures, as they often lack cognitive, communication and
social abilities to respond to questionnaires on health and
well-being. Furthermore, there is uncertainty about the
measurement of costs, for instance when and how to
measure costs for caregivers, and how to estimate and
incorporate productivity costs in economic evaluation.
Further research on methods to measure spillover effects
on family members and caregivers and productivity costs
of NDD is needed. Understanding the heterogeneity of
children with NDDs in terms of their patterns of healthcare
utilization, resources used, and dependency relationships
with caregivers is important to ensure the measurement of
costs and consequences are more representative in the
Acknowledgements The authors would like to thank Dr. David
Whitehurst, Simon Fraser University and Dr. Mike Paulden,
University of Alberta for providing comments and feedback during
the preparation of the manuscript. We gratefully acknowledge the
contributions from Kids Brain Health Network funded through The
Networks of Centers of Excellence Program and CHILD-BRIGHT
funded by CIHR.
Author Contribution Both authors contributed to the manuscript.
RL led the manuscript drafting and JZ leading conception of the
manuscript, drafting and revisions.
Compliance with Ethical Standards
Ethical approval No specific ethical approval was sought for this
Conflict of interest Ramesh Lamsal and Jennifer Zwicker work on
economic evaluations of interventions for children with NDD.
Funding RL and JZ are supported by grants from the Kids Brain
Health Network, a Network of Center of Excellence and
CHILDBRIGHT, funded by CIHR. The Social Policy and Health Research
Unit is supported by the Sinneave Family Foundation.
Open Access This article is distributed under the terms of the
Creative Commons Attribution-NonCommercial 4.0 International
License (http://creativecommons.org/licenses/by-nc/4.0/), which
permits any noncommercial use, distribution, and reproduction in any
medium, provided you give appropriate credit to the original
author(s) and the source, provide a link to the Creative Commons
license, and indicate if changes were made.
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