Owen, 2011; Young, Sigafoos, Suttie, Ashman, &Grevell, 1998). Those meta-analyses have identifiedseveral factors that are associated with variability indifferences in adaptive behavior change reported. Forexample, the Hamelin et al. (2011) meta-analysis notedchanges in adaptive behavior associated with deinsti-tutionalization were impacted by differences in level ofID, using a comparison group rather than a repeatedmeasures design, differences in the type of communitysetting to which a person moved, the choice of adaptivebehavior instrument, whether the instrument was stan-dardized, the length of the follow-up period, and thenumber of participants studied.