Quantitative Synthesis of Research Evidence: Multilevel Meta-Analysis

The quantitative summary allows for objective, evidence-based, and informed decisions in research, practice, and policy. Based on previous methodological work, the technique results in powerful, unbiased, and precise effect size estimates.

However, its use in practice is limited and its full potential is not yet fully understood. This article aims to bring the multilevel meta-analytic model closer to the applied researcher by introducing the technique at a conceptual level and discussing its full potential and relevance to the field. The procedure of multilevel meta-analysis is illustrated using a recent single-case meta-analytic dataset.