An evaluation of treatment response and remission definitions in adult obsessive-compulsive disorder: A systematic review and individual-patient data meta-analysis

Introduction: Expert consensus operationalized treatment response and remission in obsessive -compulsive disorder (OCD) as a Yale -Brown Obsessive -Compulsive Scale (Y-BOCS) reduction >= 35% and score <= 12 with <= 2 on Clinical Global Impressions Improvement (CGI-I) and Severity (CGI-S) scales, respectively. However, there has been scant empirical evidence supporting these definitions. Methods: We conducted a systematic review and an individual participant data meta -analysis of randomizedcontrolled trials (RCTs) in adults with OCD to determine optimal Y-BOCS thresholds for response and remission. We estimated pooled sensitivity/specificity for each percent reduction threshold (response) or posttreatment score (remission) to determine response and remission defined by a CGI-I and CGI-S <= 2, respectively. Results: Individual participant data from 25 of 94 eligible RCTs (1235 participants) were included. The optimal threshold for response was >= 30% Y-BOCS reduction and for remission was <= 15 posttreatment Y-BOCS. However, differences in sensitivity and specificity between the optimal and nearby thresholds for response and remission were small with some uncertainty demonstrated by the confidence ellipses. Conclusion: While the empirically derived Y-BOCS thresholds in our meta -analysis differ from expert consensus, given the predominance of data from more recent trials of OCD, which involved more refractory participants and novel treatment modalities as opposed to first -line therapies, we recommend the continued use of the consensus definitions.