Socioeconomic Deprivation and Dropout from Contemporary Psychological Intervention for Common Mental Disorders: A Systematic Review.

Dropout during psychological intervention is a significant problem. Previous evidence for associations with socioeconomic deprivation is mixed. This study aimed to review the evidence for associations between deprivation and dropout from contemporary adult psychological interventions for common mental disorders (CMDs). Systematic review, narrative synthesis and random effects meta-analysis of peer-reviewed English language journal articles published June 2010-June 2020 was conducted. Data sources included medline, PsycInfo, databases indexed by web of science, ProQuest social science database and sociology collection, and the Cochrane Library, supplemented by forward and backward citation searching. Five studies were eligible for inclusion (mean N = 170, 68% female, 60% White Caucasian, 32% dropout rate, predominantly cognitive behaviour therapy/cognitive processing therapy). Narrative synthesis indicated an overall non-significant effect of deprivation on dropout. Meta-analytic significance of controlled (k = 3) and uncontrolled (k = 4) effects depended on the measure of deprivation included for those studies using more than one measure (controlled OR 1.21-1.32, p = 0.019-0.172, uncontrolled OR 1.28-1.76, p = 0.024-0.423). The low number of included studies meant sub-group comparisons were limited, despite some tentative indications of potential differential effects. A comparator set of excluded studies showed similar uncertainty. There was limited evidence that did not overall suggest a clear significant effect of deprivation on dropout from contemporary individual CMD interventions. However, more contemporary research is needed, as effects may vary according to clinical and methodological factors, and for dropout versus non-initiation.