The effects of adapted physical education on students with Down syndrome: A meta-analysis

Objective: The purpose of this study was to synthesize findings from physical activity interventions on children and adolescents with Down syndrome. Design: The present study employed a quantitative research synthesis design. The overall conclusions of past research highlight important issues related to physical activity interventions performed on children and adolescents with Down syndrome. Methods: Standard meta-analytic procedures incorporating inclusion and exclusion criteria, literature search, coding procedures, and statistical methods were used to identify and synthesize 24 studies with 258 independent samples. Cohen’s (1988) criteria for effect sizes were used to interpret and evaluate results. Results: The average treatment effect for all TARGET intervention studies was moderate (g = -0.33; SE = 0.11; 95% C.I. = -0.55, -0.11; p = 0.003) and represented about 3 tenths of a standard deviation advantage for control groups over the treatment groups. Review of the homogeneity statistics revealed a significant heterogeneous distribution (Qт = 74.75, p \u3c 0.05) making it necessary to explain between-study variation through moderator analyses of characteristics coded for studies. In addition, an outlier analysis was conducted through evaluation of residual values and found one independent sample (Ordonez, 2006) to be an outlier (z = -5.13). This prompted the use of a “one-study” removed procedure. The single effect size was retained in the analysis as the results indicated a small change (-0.26) remaining within the 95% confidence interval. All future quantitative interventions should report all data on all outcomes regardless of their significance level. The most important considerations for the construct of physical activity interventions on children and adolescents with Down syndrome should include the delivery of content from a trained adapted physical education teacher, tasks appropriate for people with Down syndrome, and consistent testing duration to reduce the possibility of physical and cognitive regression. The overall meta-analytic findings indicate that comparing children and adolescents with Down syndrome with their typical developing peers limits our ability to draw firm conclusions on the positive effects of physical activity interventions. More data are needed from the studies to provide a better overall understanding of the current trends in research and application