Assessing the robustness of direct meta-analysis in the presence of heterogeneity

Abstract

Aim: To assess robustness of findings in recent systematic reviews of atypical antipsychotics in schizophrenia patients in the presence of heterogeneity. Methods: Relative efficacy was measured in seven direct comparisons of mean difference (MD) in average positive and negative syndrome scale total score and comparisons between conventional meta-analysis results and four alternate meta-analytic strategies using the difference in MD (Delta MD). Results: MDs in positive and negative syndrome scale total score were smaller in the conventional meta-analyses than those for three of the four analytic strategies. Such differences were small (all Delta MD <4). No considerable differences in effect size were observed in the limit meta-analysis comparison (vertical bar Delta MD vertical bar <1). Conclusion: The analyses validated the systematic review results and demonstrate the value of confirmatory sensitivity analysis.