Reverse Fragility in Cochrane Meta-Analyses with P Values 0.05 to 0.20 Requires a Robustness Dimension

Abstract

A meta-epidemiological analysis of 280 Cochrane meta-analyses with P-values between 0.05 and 0.20 reports high reverse fragility and interprets these findings as potentially indicating clinical relevance. That interpretation exceeds what the reverse fragility index can measure. Reverse fragility quantifies classification stability; it does not quantify distance from therapeutic neutrality. The two dimensions are orthogonal, so fragile near-null meta-analyses and underpowered detections of real effects can yield identical reverse fragility values. Completing the analysis with the neutrality boundary framework at the meta-analytic level discriminates between these cases and specifies which nonsignificant Cochrane results warrant a clinical relevance claim.