
What Is a Meta-Analysis? Purpose, Types, and How to Conduct One
A meta-analysis is a statistical technique that combines the quantitative results of multiple independent studies addressing the same research question. Rather than relying on the findings of any single study, it pools effect sizes across studies to produce a more precise, more powerful estimate of the true effect. The term was first introduced by Gene Glass in 1976, who defined it as "the statistical analysis of a large collection of analysis results from individual studies for the purpose of i










