Background: Definitions of dichotomous outcome terms, such as “response,” “remission,” and “recovery” are central to the design, interpretation, and clinical application of randomized controlled trials of adolescent depression interventions. Accordingly, this scoping review was conducted to document how these terms have been defined and justified in clinical trials.
Method: Bibliographic databases MEDLINE, Embase, APA PsycInfo, and CINAHL were searched from inception to February 2020 for randomized controlled trials evaluating treatments for adolescent depression. Ninety-eight trials were included for data extraction and analysis.
Results: Assessment of outcome measurement instruments, metric strategies, methods of aggregation, and measurement timing, yielded 53 unique outcome definitions of “response” across 45 trials that assessed response, 47 unique definitions of “remission” in 29 trials that assessed remission, and 19 unique definitions of “recovery” across 11 trials that assessed recovery. A minority of trials (N = 35) provided a rationale for dichotomous outcomes definitions, often by citing other studies that used a similar definition (N = 11). No rationale included input from youth or families with lived experience.
Conclusion: Our review revealed that definitions of “response,” “remission,” “recovery,” and related terms are highly variable, lack clear rationales, and are not informed by key stakeholder input. These limitations impair pooling of trial results and the incorporation of trial findings into pragmatic treatment decisions in clinical practice. Systematic approaches to establishing outcome definitions are needed to enhance the impact of trials examining adolescent depression treatment.