Details

Autor(en) / Beteiligte

• Stanley, T. D.
• Doucouliagos, Hristos
• Ioannidis, John P. A.

Titel

Beyond Random Effects: When Small-Study Findings Are More Heterogeneous

Ist Teil von

• Advances in methods and practices in psychological science, 2022-10, Vol.5 (4), p.251524592211204

Ort / Verlag

Los Angeles, CA: SAGE Publications

Erscheinungsjahr

2022

Link zum Volltext

Quelle

EZB Free E-Journals

Beschreibungen/Notizen

• New meta-regression methods are introduced that identify whether the magnitude of heterogeneity across study findings is correlated with their standard errors. Evidence from dozens of meta-analyses finds robust evidence of this correlation and that small-sample studies typically have higher heterogeneity. This correlated heterogeneity violates the random-effects (RE) model of additive and independent heterogeneity. When small studies not only have inadequate statistical power but also high heterogeneity, their scientific contribution is even more dubious. When the heterogeneity variance is correlated with the sampling-error variance to the degree we find, simulations show that RE is dominated by an alternative weighted average, the unrestricted weighted least squares (UWLS). Meta-research evidence combined with simulations establish that UWLS should replace RE as the conventional meta-analysis summary of psychological research.