The influence of the number of studies on proportion bias (and the proportion RMSE) is small, as in No Transformation Versus Canonical Transformation (Logit Transformation).

From: Results

Cover of Simulation-Based Comparison of Methods for Meta-Analysis of Proportions and Rates
Simulation-Based Comparison of Methods for Meta-Analysis of Proportions and Rates [Internet].
Trikalinos TA, Trow P, Schmid CH.

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