Meta Analysis Methods | Science Tables

The majority of researchers cited the ability to combine data from multiple studies as the primary benefit of meta-analysis methods. Meta-analysis methods have their roots in the early 20th century, when statisticians such as Ronald Fisher and Karl Pearson developed techniques for combining data from multiple studies. Gene Glass and Mary Lee Smith published seminal papers on meta-analysis in the 1970s and 1980s. Cohen's d and Hedges' g are statistical techniques used to calculate effect sizes. Fixed effects models and random effects models are statistical methods used to combine effect sizes.