Maltreatment Risk Among Children With Disabilities

Abstract

Background:
Children with disabilities are at increased risk of child maltreatment; however, there is a gap in the evidence about whether all disabilities are at equal risk and whether risk factors vary according to the type of disability.

Methods:
A population-based record-linkage study of all children born in Western Australia between 1990 and 2010. Children with disabilities were identified by using population-based registers and risk of maltreatment determined by allegations reported to the Department for Child Protection and Family Support.

Results:
Although children with disabilities make up 10.4% of the population, they represent 25.9% of children with a maltreatment allegation and 29.0% of those with a substantiated allegation; however, increased risk of maltreatment was not consistent across all disability types. Children with intellectual disability, mental/behavioral problems, and conduct disorder continued to have increased risk of an allegation and substantiated allegation after adjusting for child, family, and neighborhood risk factors. In contrast, adjusting for these factors resulted in children with autism having a lower risk, and children with Down syndrome and birth defects/cerebral palsy having the same risk as children without disability.

Conclusions:
The prevalence of disabilities in the child protection system suggests a need for awareness of the scope of issues faced by these children and the need for interagency collaboration to ensure children's complex needs are met. Supports are needed for families with children with disabilities to assist in meeting the child's health and developmental needs, but also to support the parents in managing the often more complex parenting environment.

Full text

ARTICLE
PEDIATRICS Volume 139 , number 4 , April 2017 :e 20161817
Maltreatment Risk Among
Children With Disabilities
Miriam J. Maclean, BPsych(Hons), MSc, PhD, Scott Sims, MBiostat, BSC, Carol Bower, MSC, MB, BS, PhD, FAPHM, Helen
Leonard, MBChB, MPH, Fiona J. Stanley, MD, MSC, FFPHM, FAFPHM, Melissa O’Donnell, BPsych(Hons), MPsych, Dip Ed, PhD
abstract
BACKGROUND: Children with disabilities are at increased risk of child maltreatment; however,
there is a gap in the evidence about whether all disabilities are at equal risk and whether
risk factors vary according to the type of disability.
METHODS: A population-based record-linkage study of all children born in Western Australia
between 1990 and 2010. Children with disabilities were identified by using population-
based registers and risk of maltreatment determined by allegations reported to the
Department for Child Protection and Family Support.
RESULTS: Although children with disabilities make up 10.4% of the population, they represent
25.9% of children with a maltreatment allegation and 29.0% of those with a substantiated
allegation; however, increased risk of maltreatment was not consistent across all disability
types. Children with intellectual disability, mental/behavioral problems, and conduct
disorder continued to have increased risk of an allegation and substantiated allegation
after adjusting for child, family, and neighborhood risk factors. In contrast, adjusting
for these factors resulted in children with autism having a lower risk, and children with
Down syndrome and birth defects/cerebral palsy having the same risk as children without
disability.
CONCLUSIONS: The prevalence of disabilities in the child protection system suggests a need
for awareness of the scope of issues faced by these children and the need for interagency
collaboration to ensure children’s complex needs are met. Supports are needed for families
with children with disabilities to assist in meeting the child’s health and developmental
needs, but also to support the parents in managing the often more complex parenting
environment.
Telethon Kids Institute, University of Western Australia, Perth, Western Australia.
Dr Maclean conceptualized and designed the study, and drafted the initial manuscript; Mr Sims
carried out the initial analyses, and reviewed and revised the manuscript; Drs Bower, Leonard,
and Stanley contributed to the design of the study, and reviewed and revised the manuscript; Dr
O’Donnell contributed to the conceptualization and design of the study, and critically reviewed the
manuscript; and all authors approved the fi nal manuscript as submitted.
DOI: 10.1542/peds.2016-1817
Accepted for publication Jan 26, 2017
Address correspondence to Melissa O’Donnell, PhD, Telethon Kids Institute, University of Western
Australia, 100 Roberts Rd, Subiaco, Australia, 6008. E-mail: Melissa.O'Donnell@telethonkids.org.au
PEDIATRICS (ISSN Numbers: Print, 0031-4005; Online, 1098-4275).
Copyright © 2017 by the American Academy of Pediatrics
FINANCIAL DISCLOSURE: The authors have indicated they have no fi nancial relationships relevant
to this article to disclose. To cite: Maclean MJ, Sims S, Bower C, et al. Maltreatment
Risk Among Children With Disabilities. Pediatrics. 2017;
139(4):e20161817
WHAT’S KNOWN ON THIS SUBJECT: Children with
disabilities experience elevated rates of child abuse
and neglect. Only a few population-based studies
have been conducted producing mixed evidence
regarding maltreatment risk for children with
different types of disabilities.
WHAT THIS STUDY ADDS: Children with disabilities
account for 1 in 3 substantiated maltreatment
allegations; however, maltreatment risk was not
consisten t across all disabilities. Children with
intellectual disability, mental/behavioral problems,
and conduct disorder had increased risk, but not
autism, Down syndrome, or birth defects.
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MACLEAN et al
An estimated 5.1% of children
worldwide have a moderate to severe
disability.
1 Research shows that
children with disabilities experience
elevated rates of child abuse and
neglect.
2 –
6 However, there are
critical knowledge gaps, leading US
researchers Kendall-Tackett et al
7 to
state “there is an appalling gap in the
states’ ability to protect abused and
neglected children with disabilities.”
At the most basic level, states/
countries need to know the
proportion of children within their
child protection systems who have
disabilities, and their types of
disability.
7 Risk of maltreatment is
associated with child characteristics,
such as age and ethnicity; parent
factors, such as young age, mental
health problems, and substance
abuse; and neighborhood factors,
such as socioeconomic disadvantage.
6
Families of children with disabilities
more frequently experience risk
factors associated with a higher
risk of maltreatment.
8 However,
the risk for maltreatment among
children with disabilities has not
been explored taking into account
the multiple risk factors that often
cooccur in the context of these
families.
The few population-based studies
conducted have produced mixed
evidence regarding maltreatment
risk for children with different types
of disabilities,
4,
9,
10 and it remains
unclear whether disability types,
such as intellectual disability (ID), are
associated with increased risk. The
aims of this research were to report
the prevalence of different disabilities
within the child protection system
in an Australian state, and to assess
risk of maltreatment in various types
of disability taking into account
child, family, and neighborhood risk
factors.
METHODS
Population and Data Sources
We conducted a population-based
record-linkage study of all children
born in Western Australia (WA)
between 1990 and 2010 using
de-identified administrative data.
Disability information was obtained
from 4 sources that had information
for the whole study period 1990 to
2010. The first is the WA Register of
Developmental Anomalies (WARDA),
11
which includes structural or
functional birth defects that are
present before birth and diagnosed
by age 6, and cerebral palsy. WARDA
receives notifications of birth defects
from the Midwives Notification
System, the Hospital Morbidity
Data System (HMDS), and other
services (eg, genetic, pathology, and
private practitioners). The second
is the population-based Intellectual
Disability Exploring Answers
(IDEA)
12 database, which provides
WA state data on individuals with ID
and/or autism, by using information
provided by the Disability Services
Commission for individuals of
any age with ID who are provided
with services, and the Department
of Education (individuals with
ID receiving education support,
predominantly aged 5–17 years).
The IDEA database also collects
information on severity of ID, and
for cases obtained through the
Disability Services Commission, the
probable cause by using diagnostic
information reviewed from medical
records. Cases could be classified as
caused by chromosomal disorders,
metabolic disorders, prenatal
exposure to alcohol, postnatal injury,
cultural-familial (family history of
ID/environmental disadvantage), and
so forth.
13 The third is HMDS, which
contains information on all public
and private hospital discharges,
including up to 21 diagnostic
codes by using the International
Classification of Diseases (ICD) codes
(ICD- 9: 1990–June 1999, ICD-10: July
1999–2010, see Table 1). The fourth
is the Mental Health Information
System (MHIS), containing
information on all mental health–
related public and private inpatient
admissions and public outpatient
contacts with diagnoses captured by
using ICD codes. This study has ethics
approval from the WA Department
of Health Human Research Ethics
Committee.
Disability for this article was defined
as any limitation or impairment
that may affect everyday activities
ranging from intellectual, physical,
and psychological conditions.
14
This broad definition includes
2
TABLE 1 Disability Group and Their Corresponding Codes and Databases.
Group Databases ICD-9 Codes ICD-10 Codes
ID IDEA, HMDS, MHIS 317–319 F70-F79
Down syndrome IDEA, WARDA, HMDS, MHIS 758.0 Q90
Birth defects/cerebral
palsy (all congenital
malformations and
cerebral palsy)
WARDAa
Autism IDEA, HMDS, MHIS 299.0 F84.0, F84.1
Conduct disorder HMDS, MHIS 312, 314.0 F90-F92
Mental and behavioral
disorderb (all other
mental/behavioral
disorders apart from
autism, conduct
disorder, and
intellectual disability)
HMDS, MHIS 290–316 (excluding
299.0, 312, 314.0)
F00-F69, F80-F99
(excluding F84.0,
F84.1, F90-F92
Any disability Any of the above Any of the above Any of the above
a http:// kemh. health. wa. gov. au/ services/ register_ developmental_ anomalies/ diagnostic_ codes_ birth_ defects. htm.
b This includes organic disorders, disorders due to psychoactive substance use, schizophrenia-type disorders, mood
disorders, behavioral syndromes, stress-related disorders, personality disorders, specifi c developmental disorders,
behavioral and emotional disorders.
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PEDIATRICS Volume 139 , number 4 , April 2017
psychological conditions, which
are often not diagnosed until
adolescence, as well as disabilities
typically diagnosed at birth or
soon after. Children’s disabilities
were identified through the 4 data
sources of WARDA, IDEA, HMDS and
MHIS, and disability groups were
categorized as shown in Table 1.
Disability categories were chosen
because they were consistent
with our definition, were the main
disability groups identified in the
sources, and their sample sizes were
adequate for analyses. Children
could be grouped in >1 category
if they had comorbid conditions;
however, Down syndrome (DS) was
grouped separately because it is
both a birth defect and causes ID.
Of the 54 532 children who had ID,
birth defect/cerebral palsy, autism,
conduct disorder, or a mental/
behavioral disorder, 15.6% had ≥1
comorbidities. For children with ID,
there was a high rate of comorbidity
with other conditions (62.6%).
We also included an additional
analysis of 2 birth defect categories
from the WARDA, spina bifida (n =
192) and cleft lip and/or palate
(n = 525), to compare with previous
research.
15
The disability data were linked to
records from Births Registrations
(1990–2010), the Midwives
Notification System (1990–2010),
Mortality Database (1990–2010), and
the Department of Child Protection
and Family Support (CPFS) (1990–
2010). Using probabilistic linkage of
common identifiers, such as name,
address, and birth date, the data were
linked by the Department of Health’s
Data Linkage Branch in which
extensive clerical review also was
conducted as per their process, with
a linkage quality of 97% to 98%.
16,
17
The identifiers were separated from
the clinical or service information to
maximize privacy during the linkage
process, with only de-identified
information provided to researchers.
The child’s sex, Aboriginality, birth
weight, and gestational age were
obtained from Births Registrations
and Midwives Notification System,
along with parents’ marital status
and age at the time of birth.
Neighborhood-level socioeconomic
status was determined by the Index
of Relative Social Disadvantage from
the Australian Bureau of Statistics by
using the Birth and Midwives data.
18
Five levels of disadvantage were
assigned to census collection districts
(∼200 households) ranging from
1 (most disadvantaged) to 5 (least
disadvantaged). Parents’ history of
hospital discharges and contacts
(pre- and post-birth) for mental
health, substance-related issues,
and assault-related injuries were
ascertained from HMDS and the MHIS
(1970–2010). The Mortality Register
was used to censor observations at
date of death.
The CPFS records provided data
on children’s entire history of
maltreatment allegations from birth
onward, including age of allegation
and type of maltreatment. Allegations
consist of reports made to CPFS
regarding alleged child abuse and
neglect. An allegation is substantiated
by CPFS when after investigation
there is reasonable cause to believe
the child has been, is being, or
is likely to be abused, neglected,
or otherwise harmed. After a
substantiated allegation, children
could be removed from their families
and enter out-of-home care.
Statistical Analysis
In addition to descriptive analysis,
Cox regression was used to estimate
the adjusted and unadjusted hazard
ratio (HR) and 95% confidence
interval (CI) for the time in months
from birth to first maltreatment
allegation, adjusted for disability
types and other risk factors. Results
in which the 95% CIs did not include
the null value of 1 were considered
statistically significant. Records were
censored at their date of death and
if there was no child maltreatment
allegation by the end of follow-up.
The main analyses first assessed the
HR for child maltreatment allegations
by using a dichotomous disability
covariate (disability versus no
disability), and second by using 6
dichotomous covariates (6 disability
types) in addition to adjusting for
child, family, and neighborhood risk
factors. In the categorical disability
analysis (6 disability groups),
children with comorbidities could
be categorized in >1 group (except
DS) and analyzed accordingly.
Further Cox regression analyses
investigated time to a substantiated
allegation and time to a period of
out-of-home care. In our analyses,
we assumed the values of these
covariates were determined at the
point when follow-up began on
each child (time = 0; ie, at birth) and
that these did not change over the
period of observation. As we are not
confident when diagnoses began, we
did not add a time-varying covariate
for disability and have stated this in
the limitations. Additional analyses
examined risk of allegations related
to aspects of ID, including severity,
comorbidity, cause, and the specific
birth defects of spina bifida and cleft
lip and/or palate. Further analyses
also were conducted to investigate
type of maltreatment allegation
(neglect, physical and sexual abuse)
for all disability groups and ID
severity (Supplemental Information).
RESULTS
Risk of Allegations
Of the 524 534 children in the
population cohort, 4.6% had a
maltreatment allegation ( Table 2).
Overall, 25.9% of child maltreatment
allegations and 29.0% of
substantiated allegations involved a
child with a disability. Maltreatment
allegations varied by disability type;
children with ID comprised 6.7%
allegations, similar to birth defects/
cerebral palsy (6.6%), and conduct
3
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MACLEAN et al
disorder (4.5%), with the largest
number of allegations for children
with mental/behavioral disorders
(15.6%). Only a small proportion of
allegations included children with DS
(0.1%) or autism (0.7%).
Age at first maltreatment allegation
was similar across disability types,
with a mean age of 4.8 years, and
fairly similar to children without
disabilities (4.2 years). Type of
maltreatment allegation also was
similar across disability groups
(neglect ∼25%, physical abuse
∼24%, sexual abuse ∼19%, and
emotional abuse ∼3.5%). This
pattern was generally similar to
children without disabilities, except
proportions were slightly higher for
neglect and physical abuse. The only
groups that varied to a large degree
were children with ID who had a
higher proportion of neglect (33%)
and children with conduct disorder
who had more physical abuse (31%).
Before adjusting for child, family,
and neighborhood characteristics,
children with a disability had more
than a twofold increased risk of
having a maltreatment allegation
(HR 2.64, 95% CI 2.56–2.74) and
a threefold increased risk of a
substantiated allegation (HR 3.09,
95% CI 2.97–3.22) compared with
children without a disability (see
Table 3). All disability types other
than DS were associated with a
significantly increased risk for
having a maltreatment allegation
before adjustment. The highest HRs
were for conduct disorder (HR 5.14,
95% CI 4.83–5.47), followed by ID
(HR 3.86, 95% CI 3.67–4.06) and
mental/behavioral disorders (HR
3.69, 95% CI 3.56–3.82). The risk
of substantiated allegation also was
higher.
Adjustment for Demographic and
Psychosocial Characteristics
As shown in the Supplemental Tables,
demographic and psychosocial
characteristics vary across disability
type. Accounting for child, family, and
neighborhood risk factors partially
attenuated the relationship between
disabilities and maltreatment,
particularly for conduct disorder
and mental/behavioral disorders,
and changed the relationship for
autism from increased to decreased
risk ( Table 3). After controlling for
other risk factors, children with a
disability still had an increased risk
of maltreatment allegations (HR 1.74,
95% CI 1.68–1.80) and substantiated
allegations (HR 1.89, 95% CI
1.80–1.98) compared with children
without disabilities.
Risk was highest for children with
IDs (HR 2.14, 95% CI 2.00–2.28),
followed by conduct disorder and
mental/behavioral disorders.
There was significantly lower risk
of maltreatment allegations for
children with autism (HR 0.74, 95%
CI 0.63–0.89), and children with DS
also had lower risk, although did not
reach significance (HR 0.69, 95%
CI 0.46–1.02). Risk of maltreatment
allegations did not differ between
children with birth defects/
cerebral palsy and children with no
disabilities (HR 0.99, 95% CI 0.93–
1.05), although they had a slightly
elevated risk of a substantiated
allegation (HR 1.10, 95% CI 1.01–
1.20) and entering out-of-home care
(HR 1.32, 95% CI 1.18–1.49, see
Supplemental Information). Analysis
by type of maltreatment allegation
found relatively consistent results,
with the exception of maltreatment
involving sexual abuse, in which
autism was protective and birth
defects/cerebral palsy showed no
increased risk. However, caution
should be taken when interpreting
results due to smaller sample sizes
and therefore unreliable estimates
(Supplemental Information).
Supplementary multivariate analysis
of spina bifida and cleft lip and/
or palate was conducted, finding
an increased risk of substantiated
allegation in the univariate analysis
(HR 1.94, 95% CI 1.01–3.72; HR 1.61,
95% CI 1.01–2.56, respectively), but
after adjustment found no increased
risk (HR 0.74, 95% CI 0.33–1.65; HR
0.81, 95% CI 0.42–1.55, respectively).
Caution should be taken with this
finding due to small sample size.
Aboriginal children had an increased
risk of a maltreatment allegation of
almost 6.5 times compared with non-
Aboriginal children; however, this
risk dropped to 1.64 (95% CI 1.57–
1.70) once other factors were taken
into account, particularly as they
had a higher risk of other family and
social risk factors. The proportion of
Aboriginal children with disability
was 14.2%, compared with 10.1%
for non-Aboriginal children. They
had a higher proportion of children
with ID (3.2% vs 1.5%) and mental/
behavioral disorder (17.5% versus
14.3%), both of which had higher
risks of maltreatment allegations.
Severity and Cause of ID
For children with ID, less severe
disability was related to increased
likelihood of maltreatment
allegations ( Table 4). After
controlling for other risk factors,
children with borderline-mild ID
had an almost threefold increased
likelihood of maltreatment
allegations (HR 2.73, 95% CI
2.45–3.04), and children with
mild-moderate ID were at twofold
increased likelihood of allegations
(HR 2.01, 95% CI 1.85–2.17). The
risk associated with severe ID did
not differ significantly from children
without ID (HR 1.30, 95% CI 0.95–
1.79). When broken down by type of
maltreatment allegation, the findings
were relatively consistent except
that for children with severe ID, they
were at increased risk of neglect
(Supplemental Information).
Among children with ID, a
supplementary analysis found an
increased maltreatment risk for
children for whom the recorded
cause of disability was postnatal
injury (HR 5.14, 95% CI 2.99–8.83),
prenatal exposure to alcohol (HR
2.01, 95% CI 1.30–3.11), other birth
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PEDIATRICS Volume 139 , number 4 , April 2017 5
TABLE 2 Characteristics of Study Population and Level of Child Protection Involvement
Characteristic Total No Allegation Any Allegation Any Substantiated
Allegation
Entered Out-of-Home Care
n n%n %n% n %
Number 524 534 500 518 24 016 11 560 5596
Sex
Male 268 651 257 108 51.4 11 543 48.1 5472 47.3 2810 50.2
Female 255 831 243 362 48.6 12 469 51.9 6088 52.6 2786 49.8
Aboriginality
Non-Aboriginal 492 740 475 379 95.0 17 361 72.3 7771 67.2 3506 62.7
Aboriginal 31 612 24 975 5.0 6637 27.6 3779 32.7 2085 37.3
Missing 182 164 0.03 18 0.1 10 0.1 5 0.09
Socioeconomic status
1 (most disadvantaged) 120 565 37 560 7.5 11 506 47.9 5811 50.3 2903 51.9
2 120 126 81 247 16.2 5805 24.2 2749 23.4 1335 23.9
3 99 811 66 313 13.5 3344 13.9 1550 13.4 726 13.0
4 94 009 136 417 27.3 2097 8.7 923 8.0 420 7.5
5 (least disadvantaged) 87 330 177 067 35.4 1120 4.7 445 3.8 173 3.1
Missing 2693 1914 0.4 144 0.6 82 0.7 39 0.7
Disability type
ID 8551 6952 1.4 1599 6.7 905 7.8 527 9.4
Down syndrome 552 521 0.1 31 0.1 15 0.1 8 0.1
Birth defect/cerebral palsy 30 090 28 501 5.7 1589 6.6 860 7.4 498 8.9
Autism 2253 2078 0.4 175 0.7 89 0.8 56 1.0
Conduct disorder 3924 2846 0.6 1078 4.5 573 5.0 318 5.7
Mental and behavioral
disorder
19 813 16 062 3.2 3751 15.6 2073 17.9 1004 17.9
Any disability 54 535 48 324 9.7 6211 25.9 3352 29.0 1709 30.5
Maternal age, y
<20 30 019 25 194 5.0 4825 20.1 2406 20.8 1162 20.8
20–29 252 817 239 044 47.8 13 773 57.3 6638 57.4 3162 56.5
30+ 241 642 236 228 47.2 5414 22.5 2516 21.8 1272 22.7
Missing 56 52 0.01 4 0.02 0 0.0 0 0.0
Paternal age, y
<20 9522 8107 1.6 1415 5.9 687 5.9 327 5.8
20–29 175 262 165 343 33.0 9919 41.3 4649 40.2 2074 37.1
30+ 314 549 307 078 61.4 7471 31.1 3257 28.2 1518 27.1
Missing 25 201 19 990 4.0 5211 21.7 2967 25.7 1677 30.0
Gestational age, wk
<37 38 702 35 767 7.1 2935 12.2 1606 13.9 945 16.9
37+ 485 157 464 117 92.7 21 040 87.6 9933 85.9 4642 83.0
Birth weight for gestational
age
<10th percentile 52 489 48 271 9.6 4218 17.6 2182 18.9 1164 20.8
>10th percentile 471 322 451 566 90.2 19 756 82.3 9357 80.9 4423 79.0
Marital status
Single 51 697 44 091 8.8 7606 31.7 4000 34.6 2223 39.7
Married/defacto 470 751 454 529 90.8 16 222 67.5 7436 64.3 3302 59.0
Missing 2086 1898 0.4 188 0.8 124 1.1 71 1.3
Maternal mental health–
related admission
Yes 86 956 75 459 15.1 11 497 47.9 6153 53.2 3573 63.8
No 437 578 425 059 84.9 12 519 52.1 5407 46.8 2023 36.2
Maternal substance-related admission
Yes 41 150 31 278 6.3 9872 41.1 5756 49.8 3597 64.3
No 483 384 469 240 93.7 14 144 58.9 5804 50.2 1999 26.9
Paternal mental health–
related admission
Yes 46 689 41 323 8.3 5366 22.3 2756 23.8 1506 26.9
No 477 845 459 195 91.7 18 650 77.6 8804 76.2 4090 73.1
Paternal substance-related admission
Yes 43 431 37 212 7.4 6219 25.9 3371 29.2 1932 34.5
No 481 103 463 306 92.6 17 797 74.1 8189 70.8 3664 65.5
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TABLE 3 Risk of Maltreatment Allegation and Substantiated Maltreatment Allegation by Disability
Characteristic Risk of Maltreatment Allegation Risk of Substantiated Maltreatment Allegation
Crude HR (95% CI) Adjusted HR
(Disability Yes
Versus No)a
Adjusted HR (6-Disability
Category)b
Crude HR (95% CI) Adjusted HR (Disability
Yes Versus No)a
Adjusted HR (6-Disability
Category)b
Sex
Male Ref Ref Ref Ref Ref Ref
Female 1.14 (1.12–1.17) 1.19 (1.15–1.22) 1.21 (1.17–1.24) 1.18 (1.14–1.22) 1.28 (1.22–1.33) 1.30 (1.25–1.36)
Aboriginality
Non-Aboriginal Ref Ref Ref Ref Ref Ref
Aboriginal 6.47 (6.29–6.66) 1.64 (1.57–1.71) 1.64 (1.57–1.70) 7.90 (7.60–8.22) 1.78 (1.68–1.89) 1.78 (1.68–1.88)
Socioeconomic status
1 (most disadvantaged) 7.04 (6.62–7.49) 2.65 (2.47–2.84) 2.62 (2.44–2.80) 8.83 (8.02–9.73) 2.81 (2.52–3.14) 2.78 (2.48–3.10)
2 3.54 (3.32–3.78) 2.08 (1.94–2.23) 2.07 (1.93–2.22) 4.21 (3.81–4.65) 2.34 (2.09–2.62) 2.32 (2.07–2.59)
3 2.47 (2.31–2.64) 1.70 (1.58–1.83) 1.70 (1.57–1.83) 2.89 (2.60–3.21) 1.88 (1.67–2.12) 1.88 (1.67–2.12)
4 1.72 (1.59–1.85) 1.40 (1.29–1.51) 1.40 (1.30–1.52) 1.90 (1.70–2.13) 1.47 (1.29–1.67) 1.47 (1.30–1.67)
5 (least disadvantaged) Ref Ref Ref Ref Ref Ref
Maternal age
<20 7.18 (6.90–7.46) 2.02 (1.91–2.15) 2.00 (1.88–2.12) 7.43 (7.02–7.86) 1.80 (1.65–1.96) 1.78 (1.63–1.94)
20–29 2.26 (2.19–2.33) 1.40 (1.35–1.46) 1.39 (1.34–1.45) 2.35 (2.24–2.46) 1.38 (1.30–1.47) 1.36 (1.28–1.45)
≥30 Ref Ref Ref Ref Ref Ref
Paternal age
<20 6.60 (6.23–6.99) 1.18 (1.10–1.27) 1.20 (1.11–1.28) 7.04 (6.48–7.64) 1.20 (1.08–1.33) 1.22 (1.10–1.35)
20–29 2.25 (2.18–2.32) 1.14 (1.10–1.18) 1.14 (1.10–1.18) 2.41 (2.30–2.52) 1.16 (1.10–1.23) 1.16 (1.10–1.23)
≥30 Ref Ref Ref Ref Ref Ref
Marital status
Single 4.48 (4.36–4.60) 1.56 (1.51–1.62) 1.55 (1.49–1.61) 4.97 (4.79–5.17) 1.57 (1.49–1.66) 1.56 (1.48–1.65)
Married/defacto Ref Ref Ref Ref Ref Ref
Estimated gestation
<37 wk 1.86 (1.79–1.94) 1.25 (1.20–1.31) 1.29 (1.23–1.35) 2.13 (2.02–2.24) 1.33 (1.25–1.42) 1.35 (1.27–1.44)
Birth weight for gestational age
<10th percentile 1.90 (1.84–1.96) 1.23 (1.18–1.28) 1.23 (1.18–1.28) 2.06 (1.96–2.15) 1.26 (1.19–1.33) 1.25 (1.18–1.33)
Maternal mental health–related admission
Yes 4.77 (4.65–4.90) 2.32 (2.24–2.39) 2.28 (2.21–2.36) 5.76 (5.57–5.98) 2.47 (2.35–2.59) 2.43 (2.31–2.55)
Maternal substance-related admission
Yes 8.61 (8.39–8.84) 2.82 (2.72–2.92) 2.78 (2.69–2.89) 11.68 (11.26–12.12) 3.36 (3.19–3.54) 3.33 (3.16–3.50)
Paternal mental health–related admission
Yes 2.92 (2.83–3.01) 1.68 (1.62–1.74) 1.65 (1.59–1.71) 3.12 (2.99–3.26) 1.69 (1.61–1.78) 1.66 (1.58–1.75)
Paternal substance-related admission
Yes 3.85 (3.74–3.97) 1.86 (1.79–1.93) 1.85 (1.78–1.91) 4.45 (4.28–4.64) 2.10 (1.99–2.21) 2.09 (1.98–2.20)
Any disability
Yes 2.64 (2.56–2.72) 1.74 (1.68–1.80) 3.09 (2.97–3.22) 1.89 (1.80–1.98)
ID
Yes 3.86 (3.67–4.06) 2.14 (2.00–2.28) 4.51 (4.21–4.83) 2.15 (1.96–2.35)
Down syndrome
Yes 1.15 (0.80–1.66) 0.69 (0.46–1.02) 1.08 (0.63–1.86) 0.48 (0.25–0.93)
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PEDIATRICS Volume 139 , number 4 , April 2017
defects (HR 9.49, 95% CI 2.20–
41.06), and cultural-familial (HR 4.13,
95% CI 3.01–5.66).
Comorbidity
Comorbidity was common. Of
the 8551 children with ID, 5350
(62.6%) also have at least 1 of the
following: birth defect/cerebral
palsy, autism, conduct disorder, or
a mental/behavioral diagnosis. The
presence of comorbid ID significantly
increased the likelihood of having
a maltreatment allegation for
children with birth defect/cerebral
palsy, autism, or mental health
and behavioral disorders ( Table
5). Children with autism but no ID
showed a nonsignificant increased
risk, probably due to volatility of
estimates due to small numbers.
DISCUSSION
Children with disabilities make
up 10.4% of the WA population;
however, they account for 1 in 4
maltreatment allegations and 1 in
3 substantiated allegations. This
disproportionate representation
of children with disabilities in
maltreatment allegations are
consistent with international
findings.
9 Importantly, the increased
risk of maltreatment allegations was
not consistent across all disability
types. Overrepresented groups
included children with ID, conduct
disorder, and mental/behavioral
disorders.
Previous studies have included
various disability types, but there is
no consistent method for defining
and grouping disability types, which
reduces comparability. Also, different
countries may have different
thresholds and processes around
child maltreatment allegations,
which reduces comparability.
Nevertheless, comparisons with
previous studies shed light on some
consistent findings. Unadjusted
results show significantly elevated
risk of allegations for all disability
7
Characteristic Risk of Maltreatment Allegation Risk of Substantiated Maltreatment Allegation
Crude HR (95% CI) Adjusted HR
(Disability Yes
Versus No)a
Adjusted HR (6-Disability
Category)b
Crude HR (95% CI) Adjusted HR (Disability
Yes Versus No)a
Adjusted HR (6-Disability
Category)b
Birth defect/cerebral palsy
Yes 1.12 (1.06–1.18) 0.99 (0.93–1.05) 1.27 (1.19–1.37) 1.10 (1.01–1.20)
Autism
Yes 1.53 (1.32–1.78) 0.74 (0.63–0.89) 1.65 (1.34–2.03) 0.87 (0.68–1.11)
Conduct disorder
Yes 5.14 (4.83–5.47) 1.84 (1.70–1.98) 5.57 (5.12–6.06) 1.74 (1.56–1.93)
Mental and behavioral disorder
Yes 3.69 (3.56–3.82) 1.62 (1.55–1.69) 4.37 (4.17–4.59) 1.74 (1.64–1.85)
Ref, reference category.
a Adjusted by sex, Aboriginality, socioeconomic status, maternal age, paternal age, marital status, estimated gestation, birth weight for gestational age, parental mental health–related admissions, parental substance-related admissions and
whether they had a disability.
b Adjusted by sex, Aboriginality, socioeconomic status, maternal age, paternal age, marital status, estimated gestation, birth weight for gestational age, parental mental health–related admissions, parental substance-related admissions and
disability groups.
TABLE 3 Continued
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MACLEAN et al
types except DS, with a more than
threefold increased risk of allegations
for mental/behavioral disorders,
conduct disorder, and ID. After
adjusting for risk factors, children
with ID, mental/behavioral problems,
and conduct disorder continued to
have increased risk of allegations and
substantiated allegations, consistent
with previous research.
4,
9,
10 Likewise,
children with ID continued to
have increased risk of allegations,
consistent with some but not all
previous population studies.
4, 9
In contrast, after adjustment, children
with autism, DS, and birth defects/
cerebral palsy showed no increased
risk for an allegation; however,
for substantiated maltreatment,
children with birth defects/cerebral
palsy had a slightly increased risk,
which just reached significance.
Our results of no increased risk for
autism and DS are consistent with
previous research despite different
lengths of follow-up.
4,
9 However,
our finding of no increased risk for
spina bifida or cleft lip and/or palate
after adjustment was the opposite of
previous findings.
15
Possible explanations for the lower
risk for children with DS and autism
include that these disabilities are
comparatively well recognized,
understood, and supported.
Parents tended to be older, better
off socioeconomically, and for DS,
the ready availability of prenatal
screening in WA means most parents
have had the opportunity for prenatal
diagnosis and the choice to continue
with the pregnancy.
19
We cannot specifically address the
directionality of maltreatment and
disability in our study. However,
the stronger relationship between
disability types that could be
caused by or share a pathway with
maltreatment is consistent with
studies that found the relationship
with maltreatment was stronger
(eg, Sullivan and Knutson
9) or
present (eg, Spencer et al
4) only for
disabilities such as conduct disorder,
mental/behavioral problems, and
ID. Together with our examination
of the recorded cause of ID, finding
increased risk for postnatal injury,
prenatal exposure to alcohol, and
cultural-familial causes lends
further support to this. As an
example of potential complexities,
the case of maternal alcohol use
during pregnancy (causing ID) and
continuing after birth may affect
parenting a child with complex
needs resulting in child protection
involvement. This should be
examined in future research.
Regardless of causality, the disability
types most strongly associated with
maltreatment often cooccurred with
a constellation of other risk factors,
such as parents who are young or
who have been hospitalized for
mental health or substance use,
and living in more disadvantaged
neighborhoods. These families
already face additional stressors
and have fewer resources to access
services for their children’s special
needs.
The inverse relationship
between severity of ID and risk
of maltreatment is consistent
with other research.
3 It has been
suggested that where children’s
disabilities are more profound,
parents may have more realistic
expectations, or children may be
less able to function in ways that
are provocative (eg, talking back).
Furthermore, clustering of mild ID
within families is relatively common,
and linked to socioeconomic
disadvantage.
20 In combination with
our finding that ID with cultural-
familial causes was associated with
increased maltreatment, it may be
that a number of children with mild
ID are more likely to experience
maltreatment because they have
a higher-risk family profile. It is
important that qualitative research
investigates further factors that may
increase risk and identify support
strategies and interventions that may
assist families.
The relationship between disability
and child maltreatment was partially
attenuated after adjusting for
demographic and psychosocial risk
factors. These findings indicate that
disability is an important risk factor
8
TABLE 4 Risk of Maltreatment Allegation by Severity of ID
Severity of ID Number Multivariate HRa
Borderline-mild 2775 2.73 (2.45–3.04)
Mild-moderate 4077 2.01 (1.85–2.17)
Severe 552 1.30 (0.95–1.79)
Unknown 1147 1.57 (1.22–2.03)
No ID 515 983 Ref
Ref, reference category.
a Adjusted by sex, Aboriginality, socioeconomic status, maternal age, paternal age, marital status, estimated gestation,
birth weight for gestational age, parental mental health–related admissions, and parental substance-related admissions.
TABLE 5 Risk of Maltreatment Allegation by Comorbidity With IDs
Disability Group (With and Without ID)aNumber Multivariate HRb
Down syndrome 552 0.77 (0.51–1.17)
Birth defect/cerebral palsy with ID 2606 1.78 (1.54–2.04)
Birth defect/cerebral palsy no ID 27 484 0.96 (0.90–1.02)
Autism with ID 2120 1.21 (1.02–1.45)
Autism no ID 133 1.71 (0.92–3.19)
Conduct with ID 485 1.83 (1.51–2.23)
Conduct no ID 3439 1.92 (1.78–2.08)
Mental disorders with ID 1587 2.13 (1.86–2.43)
Mental disorders no ID 18 226 1.63 (1.55–1.70)
a Reference group is children not in that disability group.
b Adjusted by sex, Aboriginality, socioeconomic status, maternal age, paternal age, marital status, estimated gestation,
birth weight for gestational age, parental mental health–related admissions, and parental substance-related admissions.
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PEDIATRICS Volume 139 , number 4 , April 2017
for maltreatment, but not all disabled
children should be considered at
increased risk, and that other risk
factors at the child, family, and
neighborhood levels also play an
important role. From our analyses,
socioeconomic disadvantage, teenage
parents, maternal mental health,
and substance use admissions were
strong risk factors for maltreatment.
Factors at these different levels need
to be considered when assessing the
needs of families to ameliorate risks.
Although the use of administrative
data allows complete case
ascertainment of children with
maltreatment allegations from
birth onward in WA, it does have
limitations. Obviously, maltreatment
will be included only if it is reported.
Although we have comprehensively
ascertained disability from a number
of population-level data sources, not
all children with disabilities will be
identified. Comorbidities also will
be underascertained, as the MHIS
captures only 1 diagnosis. During
the study period, it is expected
that there would be changes in the
prevalence of diagnoses over time,
which would have affected the
prevalence of ICD codes. For example,
previous research found a rise in
the prevalence of autism diagnoses
in 1994 with the introduction of the
Diagnostic and Statistical Manual
of Mental Disorders, Fourth Edition,
and in 1997 with the formalization
of assessment procedures.
21 In
addition, a number of important
variables could not be obtained
using our data, including the child’s
level of functioning, age of diagnosis,
type and amount of support services
families are receiving, family
functioning, and parents’ own
disability status. The other issue is
the timing of the onset of disability/
condition in relation to maltreatment
to provide further evidence of
directionality, whether maltreatment
may be a cause for some conditions
(eg, conduct disorder) or contributes
as a risk factor to maltreatment. We
also cannot rule out that children
with disabilities are likely to have
increased service use; therefore,
higher scrutiny and increased
likelihood to be reported for
maltreatment, which should be
considered in future research.
The prevalence of disabilities in
the child protection population
suggests the need for awareness
by agencies of the scope of issues
faced by children in the system and
interagency collaboration to ensure
children’s complex needs are met.
In addition, supports are needed for
families of children with disabilities
not only to assist in meeting the
child’s health and developmental
needs, but also to support parents in
managing the often more complex
parenting environment, including
dealing with challenging behavior.
Research indicates that family-
centered care with coordination
of services, continuity of care, and
respite care are important factors
in reducing child protection risk.
22,
23 As signatories to the United
Nations Conventions on the Rights
of the Child and Rights of Persons
with Disabilities, governments
have committed to assist parents
in the performance of their child-
rearing responsibilities, and that
persons with disabilities and their
family members should receive
the necessary assistance to enable
families to contribute toward the
full and equal enjoyment of the
rights of persons with disabilities.
This highlights the important role
governments and society have
in ensuring that children with
disabilities and their families have
the appropriate services and support
structures in place to enable them
to achieve their full potential and
ensure their well-being.
ACKNOWLEDGMENTS
The authors acknowledge the
partnership of the WA Government
Departments of Health, Child
Protection, Education, Disability
Services, and Corrective Services and
the Attorney General who provided
support as well as data for this project.
This article does not necessarily
reflect the views of the government
departments involved in this research.
We also thank the WA Data Linkage
Branch for linking the data.
9
ABBREVIATIONS
CI: confidence interval
CPFS: Department of Child
Protection and Family
Support
DS: Down syndrome
HMDS: Hospital Morbidity Data
System
HR: hazard ratio
ICD: International Classification
of Diseases
ID: intellectual disability
IDEA: Intellectual Disability
Exploring Answers
MHIS: Mental Health Information
System
WA: Western Australia
WARDA: Western Australian
Register of
Developmental
Anomalies
FUNDING: This work was supported by an Australian Research Council Linkage Project Grant (LP100200507) and an Australian Research Council Discovery Grant
(DP110100967). Dr O’Donnell is supported by a National Health and Medical Research Council Early Career Fellowship (1012439).
POTENTIAL CONFLICT OF INTEREST: The authors have indicated they have no potential confl icts of interest to disclose.
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MACLEAN et al
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