3.2 Datasynthesis3.2.1 DropoutratesExaminationofdropoutratesshowedasignificantlygreaterlikelihoodof dropout in CBT compared to placebo (OR = 1.35, 95% CI = 1.05–1.77, P < .05). The weighted mean dropout rate across all studies was24.0% in CBT and 17.2% in placebo. This difference in dropout rates was largely due to a greater attrition rate in the 14 studies examiningPTSD (29.0% in CBT vs. 17.2% in placebo), which had an OR of 1.82(95% CI = 1.32–2.52, P < .01). With PTSD studies removed, the differ- enceindropoutbetweenCBT(19.6%)andplacebo(17.2%)reducedto nonsignificance(OR = 1.10,95%CI = 0.78–1.55, P = n.s.).