The Efficacy of Special Versus Regular Class Placement for Exceptional Children: a Meta-Analysis
Fifty primary research studies of special versus regular class placement were selected for use in a meta-analysis. Each study provided a measure of Effect Size (ES), defined as the posttreatment difference between special and regular placement means expressed in standard deviation units. ES was used as a dependent variable in order to assess the effects of independent variables such as placement; type of outcome measure; internal validity; and other educational, personological, and methodological variables. Special classes were found to be significantly inferior to regular class placement for students with below average IQs, and significantly superior to regular classes for behaviorally disordered, emotionally disturbed, and learning-disabled children. Other independent variables bore little or no relationship to ES.