This book brings together the evidence-base in a number of areas that are of importance to children and adults with developmental disabilities (including intellectual disabilities and people on the autism spectrum). It includes information on diagnosis, assessment and intervention, reviewing the strength of the evidence within each area. It is applicable to a number of different environments including schools, community-based and in-patient units, and will be of interest to people who support individuals directly (including family members), provide services for or carry out research in this area.
Whilst the authors are not explicit in what they are defining as a psychosocial intervention, they seem to be using a broad definition. Dagnan (2007) suggests that psychosocial interventions include those carried out with the individual, within the immediate social context of the person, within the wider context (e.g. leisure or employment) and should include the service structures within which interventions are delivered (e.g. a model of early intervention).
What is evidence-based practice (EBP)?
The book begins with an outline of a number of situations in which families, educators, clinicians and service providers need to engage with the evidence-base to be able to make informed decisions about the lives of people with intellectual and developmental disabilities (IDD). This might involve thinking about the use of a specific approach with an individual or the adoption of an intervention strategy more widely, such as early intervention. The authors present definitions of EBP. They outline their approach for assessing the quality of the evidence and point out that, rather than the aim being to generate of a list of “approved” interventions, we need to engage with:
[…] the application and adaptation of research findings to the actual effective delivery of the best intervention to real-world clients in real-world settings by local practitioners to achieve actual client outcomes for the specific client at hand (p. 5).
They cite lack of reference to the evidence-base as one factor contributing to the poor quality of professional training in IDD in this area. They suggest that differences in understandings may lead people to dismiss some EBP. Professional disagreements may of course exist about the nature of the problem. For example, a particular behaviour may be seen as being “caused by” an underlying depression, the reinforcement of behaviour in similar circumstances, hypersensitivity to noise, etc. and such understandings will have an impact not only on the intervention target/s and the intervention approach but also on understandings about the criteria by which success ought to be measured.
EBP is presented through reviews of meta-analyses of psychosocial interventions for people with IDD. Meta-analyses compare and contrast results from the research that has previously been carried out. Having defined what is meant by EBP, the first part of the book goes on consider:
Adaptive behaviour, where the authors argue that there is strong evidence that we can teach a wide range of skills, with most evidence for behavioural methods.
Maladaptive behaviour, where the authors conclude that almost all the evidence relates to behavioural and behaviour analytic intervention. They also highlight that research to date has mostly been concerned with children and adolescents, with much less evidence with regard to adults.
The final chapter of this section looks at:
But is it worth it? Thinking of those who commission services, they argue that EBP is needed to ensure that the resources available are used in the most cost-effective manner. This chapter reviews economic evaluations of psychosocial treatments, noting the rather limited data available. The authors conclude that toilet training, supported employment and early intensive behavioural intervention for autism are promising interventions in terms of their cost-effectiveness.
Specific disorders
Part 2 of the book includes chapters on:
aggressive behaviour;
self-injurious behaviour;
stereotypic behaviour;
feeding problems;
sleep problems;
anxiety disorders;
mood disorders; and
offenders with developmental disabilities.
Each chapter concludes with a very useful set of guidelines and recommendations which pull together the knowledge gained from a review of the available data. They are designed to be used to aid the dissemination of EBP and increase its use within clinical practice in a wide variety of settings.
The editors rightly point out that we now need to:
turn our attention to evaluation of approaches within everyday settings;
think about generalisation issues;
focus on long-term effectiveness;
consider cost benefits; and
continue to evaluate new approaches as they evolve.
This book is likely to be of great use to professionals and researchers working in the field of IDD. It applies a much needed scientific approach. It may be rather less accessible to parents and some other groups. Dividing the chapters in Part 2 so that each focused on a different issue meant that there was a considerable amount of repetition within the clinical guidelines. Perhaps a concluding chapter pulling together some of the common areas might have been useful.
