Effects of Graphic Organizers on Outcomes for Students with Disabilities: Three-Level Meta-Analysis of Single-Case Studies

This study employed a meta-analytic approach to examine the effectiveness of graphic organizers (GOs) in improving academic and behavioral outcomes for K-12 students with disabilities, drawing from the single-case special education literature. Moderators at participant and study level were analyzed in addition to the main effects. A comprehensive search yielded 47 studies that met the inclusion criteria, making data available on 184 participants and 5,065 repeated measures. Employing a multivariate multilevel meta-analysis, the present study explored the efficacy of GO interventions while considering various moderators at the participant and study levels. The findings revealed that use of GOs is an effective strategy for enhancing academic performance among students with disabilities, including those with learning disabilities and various other disabilities, across multiple academic domains. However, despite the large number of studies included in the meta-analysis, only limited conclusions can be drawn with respect to the differential effectiveness of GO interventions, since the papers focused primarily on language skill acquisition, and many did not adequately document the moderators. Recommendations include future research addressing these limitations.