Mega-Analysis of Meta-Analyses

Conflicting reports on the effectiveness of these approaches abound-but meta-analysis can help sort out overall benefits and weaknesses of these and other educational practices . This article reports on some of these broad studies of research that seem to indicate effectiveand noneffective-teaching strategies. But as special educators all know, the most important consideration is a knowledge of what works with your individual student, as well as a compelling curiosity that leads you to read the meta-analyses for yourself. In meta-analysis, a researcher examines many studies on a particular strategy and derives a numerical indicator of the relative effectiveness of the strategy , averaged across all studies. This indicator is called an effect size (ES) (see box, "How Meta-analysis Works"). Such an analysis of research not only provides a numerical indicator of the relative effect of a particular intervention, but the effect size also allows comparison with other approaches used in special education or related services.