A Systematic Review of Weighted Vests with Individuals with Autism Spectrum Disorder. Taylor, C. J., Spriggs, A. D., Jones Ault, M., Flanagan, S., & Sartini, E. C. (2017)
Many occupational therapists have reported using weighted vests in their work with children with ASD. Those who use weighted vests claim that these vests help a child process sensory information and lower arousal levels, resulting in the child demonstrating increased attention and decreased stereotypic behavior. Although some of the ideas for the use of weighted vests are based on knowledge of the brain and interactions with sensory perception in the body, the theory has not been tested enough to know if it is accurate. This paper reviews existing studies that have been conducted to determine whether or not weighted vests can be considered evidence-based practice in the treatment of ASD.
How was this studied?
The authors did an extensive search of the scientific literature to find studies published on the effectiveness of weighted vests for children with ASD. They then used the standards recommended by the What Works Clearinghouse (WWC) to evaluate which studies could be included in the review. WWC is part of the Institute of Education Sciences, within the US Department of Education, that regularly conducts reviews on research for different programs, products, practices, and policies in education. Their standards involve a systematic, detailed way to determine how scientifically sound a study is or how much the results can be “trusted” as high quality. In other words, studies examining the use of weighted vests were reviewed to see if weighted vests improved the behavior of children with ASD consistently across multiple studies in many different geographical locations. Based on the WWC standards, the authors reviewed seven articles that included 32 individual studies of weighted vests with children with ASD.
What was the outcome?
Just over half of the studies reviewed did not have enough scientific qualities to evaluate the effectiveness of weighted vests. Of the remaining 13 studies, eight demonstrated that weighted vests did not change the behavior of children with ASD (~62% of studies indicating not effective). The other five studies did not demonstrate sufficient evidence to consider weighted vest use an evidence-based practice. Specifically, there were not enough participants who showed behavior change and had only been researched by two research teams, which indicates that evidence is still needed before use of weighted vests can be considered an evidence-based practice.
What are the strengths and limitations of the study?
Strengths: This review uses objective criteria to determine whether an intervention is evidence-based. These objective criteria are widely accepted as a standard that have been used across many researchers and for many interventions.
Limitation: The objective criteria used do not include procedural fidelity, or the degree to which the intervention is implemented appropriately during a study (i.e., if the therapist does what he/she is supposed to).
What are the implications?
Based on the conclusions from this review, weighted vests cannot be considered an evidence-based practice for individuals with ASD at this time. This means that more research is needed to determine if the intervention has any real effect on improving the lives of individuals with ASD. Readers are directed to many of the available evidence-based practice guides available through the IES: What Works Clearinghouse, The National Professional Development Center on Autism Spectrum Disorders (Frank Porter Graham Institute at the University of North Carolina), and The National Autism Center at May Institute – National Standards Project.