Figshare data Heterogeneity.xlsx

<b>Background</b> Heterogeneity among the primary studies included in a systematic review is one of the most challenging considerations for systematic reviewers. Current practices in anesthesiology systematic reviews have not been evaluated, but traditional methods may not provide sufficient information to evaluate the true nature of these differences. We address these issues by examining the practices of systematic reviewers for evaluating heterogeneity in anesthesiology reviews. We also propose a mapping method for presenting heterogeneous aspects of the primary studies in systematic reviews. <b>Methods</b> We evaluated heterogeneity practices reported in systematic reviews published in highly ranked anesthesiology journals. Elements extracted from the SRs included heterogeneity tests, models used, analyses conducted, plots used to display heterogeneity, and significant p-values. We also extracted all I² values from the SRs to quantify the level of heterogeneity. Additionally, we selected a systematic review develop an evidence map in order to display clinical heterogeneity. <b>Results</b> Our statistical analysis showed 150/207 SRs reporting a test for statistical heterogeneity. Of the 150 SRs, 138 reported the use of a plot to display statistical heterogeneity. Subgroup analyses were the most commonly reported analysis (54%). Meta-regression and sensitivity analyses were used sparingly (25%; 23% respectively). A random effects model was most commonly reported (33%); however, most SRs did not report this information (38%). Heterogeneity statistics across meta-analyses suggested that, in our sample, the majority (55%) did not present sufficient heterogeneity to be of great concern. <b>Conclusions</b> Many reviews did not provide sufficient detail regarding heterogeneity. We are calling for improvement to reporting practices.