Research on the Efficacy of Sensory Integration Therapy: Past, Present and Future

The Use of Weighted Vests with Children with Autism Spectrum Disorders and Other Disabilities

“…If so, what objective and replicable procedures should be used to make this diagnosis? The present corpus of studies provides very little coherent guidance on this matter, consistent with other recent research on sensory integrative therapy (see Leong and Carter 2008).…”

“…It is clear that consistent positive effects of the wearing of weighted vests have not been demonstrated, a finding consistent with research on sensory integration therapy in general (see Arendt et al 1988;Baranek 2002;Dawson and Watling 2000;Hoehn and Baumeister 1994;Hyatt et al in press;National Research Council 2001;Leong and Carter 2008;New York State Department of Health 1999;Perry and Condillac 2003;Roberts 2004;Shaw 2002;Vargas and Camilli 1999). In four of the studies examined, the vests had no clinically significant effect on behavior.…”

“…Consistent with research on traditional sensory integration therapy (see Arendt et al 1988;Baranek 2002;Hoehn and Baumeister 1994;Leong and Carter 2008;Schaffer 1984) the quality of much of the research examining weighted vests was quite poor. VandenBerg (2001) justified the use of a weak AB design on the basis that withdrawal of an apparently effective intervention would have been unethical, a surprising argument given the intervention was only in place for about 30 min daily.…”

“…This approach is not widely employed in small n research and is inherently problematic. In contrast to standard deviations calculated for group data, repeated measurement of the behavior of a single individual would be expected to be correlated with consequent constraint of standard deviation values and inflated effect sizes (Leong and Carter 2008). For example, in a sample of 100 AB panels from small n studies reported by Matyas and Greenwood (1990), the median effect size was 9.2 while the 25th percentile was 4.7 and the 75th was 17.1 (in comparison, in group research an effect size of 1 is considered large).…”

“…VandenBerg (2001) justified the use of a weak AB design on the basis that withdrawal of an apparently effective intervention would have been unethical, a surprising argument given the intervention was only in place for about 30 min daily. This line of reasoning has been presented previously in relation to sensory integrative therapy (see Leong and Carter 2008). In general terms it can be strongly argued that the potential harm of relatively short-term denial of treatment in order to evaluate efficacy is much less than the long-term harm in investing time and resources in a potentially ineffective intervention.…”