Assignment: Prospective Case Control Study

Assignment: Prospective Case Control Study

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H. F. Wright1 • S. Hall1 • A. Hames1 • J. Hardiman1,4 • R. Mills2,3 •

PAWS Team4 • D. S. Mills1

Published online: 2 April 2015

� The Author(s) 2015. This article is published with open access at Springerlink.com

Abstract This study describes the impact of pet dogs on

stress of primary carers of children with Autism Spectrum

Disorder (ASD). Stress levels of 38 primary carers ac-

quiring a dog and 24 controls not acquiring a dog were

sampled at: Pre-intervention (17 weeks before acquiring a

dog), post-intervention (3–10 weeks after acquisition) and

follow-up (25–40 weeks after acquisition), using the Par-

enting Stress Index. Analysis revealed significant im-

provements in the intervention compared to the control

group for Total Stress, Parental Distress and Difficult

Child. A significant number of parents in the intervention

group moved from clinically high to normal levels of

Parental Distress. The results highlight the potential of pet

dogs to reduce stress in primary carers of children with an

ASD.

Keywords ASD � Autism � Child � Family � Carer � Dogs � Intervention

Introduction

Autism spectrum disorder (ASD) is a heterogeneous con-

dition defined by the DSM-5 as a person experiencing

persistent difficulties in social interaction in a range of

contexts and as showing restricted, repetitive behaviours.

These problems must have been evident in early childhood,

cause significant impairment in functioning and not be

explainable by intellectual disorders or developmental de-

lays (DSM-5, APA 2013). Parenting children with devel-

opmental disorders, such as ASD is associated with higher

levels of stress, anxiety and negative outcomes (such as

depression and social isolation) when compared to par-

enting typically developing children, or children with other

non-developmental disabilities (Dunn et al. 2001; Koegel

et al. 1992; Weiss et al. 2013; Wolff et al. 1989). High

levels of stress impact not only on the health and wellbeing

of the carers themselves, but can also limit the effective-

ness of the outcomes of ASD interventions (Robbins et al.

1991; Osborne et al. 2008). As such the assessment of

interventions and lifestyle choices that effectively reduce

carer stress is a critically important area for research in

ASD treatment programmes.

The availability of social support and levels of stress

experienced have been associated with successful adapta-

tion of the carer (Koegel et al. 1992; Konstantareas and

Homatidis 1989; Weiss et al. 2013). It has been suggested

that the type of social support may relate to the effective-

ness of stress buffering, with more informal social support

(e.g. spouse, family, friends) acting as a more effective

stress buffer compared to formal or structured social sup-

port (e.g. parenting support groups) (Boyd 2002). Given

that informal social support may be an effective reme-

diation tool for reducing stress in carers it is appealing to

investigate the potential of companion animals, such as pet

Richard Mills was affiliated to the National Autistic Society, London,

UK, while the time of this study.

& H. F. Wright hwright@lincoln.ac.uk

1 School of Life Sciences, Joseph Banks Laboratories,

University of Lincoln, Lincoln LN6 7DL, UK

2 Research Autism, Adam House, 1 Fitzroy Square,

London W1T 5HE, UK

3 Department of Psychology, University of Bath, Bath, UK

4 Dogs for the Disabled, Frances Hay Centre,

Banbury, Oxfordshire OX17 2BS, UK

123

J Autism Dev Disord (2015) 45:2531–2540

DOI 10.1007/s10803-015-2418-5

dogs to provide informal social support for parents of

children with ASD.

It could be proposed that because carers already expe-

rience high levels of physical and emotional demands, the

demands of acquiring a pet might increase rather than re-

duce stress. However, there is increasing evidence to sup-

port stress reducing and health enhancing benefits of pets

on individuals and families (Allen et al. 2001; Friedman

and Thomas 1995). Dog ownership has been found to be a

positive factor in supporting individuals in difficult times,

including children affected by serious illness and death of a

parent (Raveis et al. 1993) and in reducing the symptoms

of physical and psychological illness in women coping

with the loss of a loved one (Barker and Barker 1988).

Furthermore, companion animals have been shown to re-

duce the onset and severity of stress-related conditions

(Wilson 1991). Additionally, there is evidence to support

the utility of trained assistance dogs as therapy for children

with ASD (Solomon 2010; Berry et al. 2013), with benefits

such as enhancing family freedom (Burrows et al. 2008),

reducing child stress (Viau et al. 2010) and improving the

effectiveness of therapy sessions (Silva et al. 2011). These

effects are remarkable in themselves for the benefits they

provide for the child with ASD, but they may also induce a

wider positive impact upon parental stress levels, par-

ticularly in circumstances where the dog lives as part of the

family as opposed to being a part of structured therapy

sessions. Indeed, a study by Burgoyne et al. (2014) report

an increase in caregiver competence, although not care-

giver strain, in families living with a trained assistance dog.

The limited number of studies which have explored the

effects of pet dogs in families with children with ASD,

have primarily focused on outcomes related to the child

with the ASD diagnosis. For instance, a recent study by

Grandgeorge et al. (2012) showed that parents reported an

increase in prosocial behaviours in their child with ASD

and a reduction in anxiety with the acquisition of a pet

(including cat, dog and small furry animal). Such beneficial

effects in child behaviours may improve parental stress.

Alternatively, because pet dogs interact with the entire

family unit it is also possible that the dog may elicit similar

stress reducing effects directly in the parent. The only other

(known) study looking at the effects of pet (as opposed to

service/assistance) dogs reports parental opinions on their

perceived benefits and limitations of acquiring a dog in the

family (Carlisle 2014). Indeed, it is important that parents

acquire a dog after careful consideration of both the po-

tential benefits and negative implications of dog ownership.

Due to both the individual nature of ASD and the charac-

teristics of dogs as unique living species it is unlikely that

dog ownership will benefit all families in the same way.

Therefore, whilst the purpose of this paper is to report data

illustrating positive effects of pet dogs for parents of

children with ASD we are keen to point out pet dogs as

effective ASD therapy is still in its infancy and requires

greater scientifically robust evaluations. Our research team

has investigated parental expectations of acquiring a pet

dog and observed some noticeable disparities between

expectations and reality which are important for practi-

tioners and parents to consider when thinking about dog

ownership (Wright, Hall, Hames, Hardiman, Burgess, Mills

and Mills, under review).

As previously mentioned parental stress levels are

thought to be important determiners in the success of ASD

therapy programmes (Robbins et al. 1991; Osborne et al.

2008), therefore, one important stage in developing un-

derstanding of animal companionship in ASD therapy is to

investigate the impact of dog ownership on parent stress.

Given the potential combined benefits for the parent, child

and whole family, pet dogs may be a widely acceptable and

flexible lifestyle change which reduces stress in the carers

of children with ASD. Furthermore, there are many po-

tential benefits of dogs as an intervention in this context;

they are accessible, socially valid and acceptable in most

western cultures, therefore, the aim of this study was to

assess the impact of acquiring a family pet dog on the stress

of carers of a child with ASD.

Methods

The research process was approved by the University of

Lincoln’s ethics committee.

Participants

Participants were recruited to take part in the study if their

child had a confirmed diagnosis of autism spectrum dis-

order. Because of the heterogeneous nature of ASD we did

not include a strict exclusion criterion for participation, in

order to obtain a sample that reflected the disparity of

characteristics of families in the general population. The

stipulations for participation were that the child was aged

between 2 and 16 years and had had received a clinical

diagnosis of ASD through Children and Adolescent Mental

Health Services (CAMHS), ASD diagnosis was confirmed

verbally by the parents. Parents looking to acquire a family

pet dog were recruited on a voluntary basis via Dogs for the

Disabled’s PAWS (Parents Autism Workshops and Sup-

port) network (Dogs for the Disabled 2013). The PAWS

program involves a series of three professional workshops

that educate parents about dog behaviour, welfare, and

training, whist advising on the suitability of, and integra-

tion of pet dogs into families with children with ASD. In

addition, postings on websites and social networks related

to Dogs for the Disabled and the National Autistic Society

2532 J Autism Dev Disord (2015) 45:2531–2540

123

(NAS), and word of mouth were used to increase the

number of participants. Demographic data relating to the

child, dog and family were collected. A control group of

parents who did not acquire dogs were recruited through

PAWS and local networks and sampled at matched time-

scales. All parents confirmed they were the primary carer

of the child. All parents in the intervention group acquired

a dog during the study (from Baseline to Post-Interven-

tion), all parents in the control group did not acquire a dog,

or live with a dog during any of the sampling points within

the study.

Intervention Group Participants (Families with a Child

with ASD Acquiring a Pet Dog)

Ninety-three carers were initially recruited into the inter-

vention group; of these, 82 completed the baseline sample

data. Eight of the 11 that dropped out before this time

reported that they had decided not to get a dog within the

timescale of the study (five of these transferred to the

control group), two acquired a dog prior to baseline and so

were excluded; the remaining carer was un-contactable.

Sixty carers provided data in both the baseline (BL) and

post-intervention (PI) samples. Of the 22 that dropped out

between BL and PI, 11 reported that they would not be

acquiring a dog within the study timescale (one of these

transferred to the control group), two were outside of the PI

sampling window, two requested to drop out of the re-

search, four were un-contactable, one got a trained assis-

tance dog and two acquired dogs but subsequently re-

homed them prior to the PI sample (reasons: carer #038

reported that the dog was biting the children, carer #079

was allergic to the dog).

Forty-two carers provided data at all three sample points

(baseline, post-intervention and follow-up); 18 dropped out

between PI and follow up (FU). Of these eight re-homed the

dogs (six due to child-dog issues, one due to child problems

unrelated to the dog, one due to dog training problems un-

related to the child), one requested to drop out of the re-

search, one was not contactable, and seven were outside of

the study timescale (i.e. the date of dog acquisition meant

that it was too late to include them in the follow up sample).

In line with the instructions in the PSI manual (Abidin

1995), four carers were removed from the data set as they

had extremely low ‘Defensive Responding’ scores, indi-

cating that their responses may be strongly biased to pre-

sent a favourable impression.