Inconsistent results for Peto odds ratios in multi‐arm studies, network meta‐analysis and indirect comparisons

The Peto odds ratio is a well‐known effect measure in meta‐analysis of binary outcomes. For pairwise comparisons, the Peto odds ratio estimator can be severely biased in the situation of unbalanced sample sizes in the two treatment groups or large treatment effects. In this publication, we evaluate Peto odds ratio estimators in the setting of multi‐arm studies and in network meta‐analysis using illustrative examples. We observe that Peto odds...