World Health Organization's low‐intensity psychosocial interventions: a systematic review and meta‐analysis of the effects of Problem Management Plus andStep‐by‐Step

Abstract

Many societies have been recently exposed to humanitarian and health emergencies, which have resulted in a large number of people experiencing significant distress and being at risk to develop mental disorders such as depression, anxiety and post‐traumatic stress disorder. The World Health Organization has released a series of scalable psychosocial interventions for people impaired by distress in communities exposed to adversities. Prominent among these is a low‐intensity transdiagnostic psychosocial intervention, Problem Management Plus (PM+), and its digital adaptation Step‐by‐Step (SbS). This systematic review is the first to summarize the available evidence on the effects of PM+ and SbS. Up to March 8, 2023, five databases were searched for randomized controlled trials examining the effects of PM+ or SbS on distress indicators (i.e., general distress; anxiety, depressive or post‐traumatic stress disorder symptoms; functional impairment, self‐identified problems) and positive mental health outcomes (i.e., well‐being, quality of life, social support/relationships). We performed random‐effects multilevel meta‐analyses on standardized mean differences (SMDs) at post‐intervention and short‐term follow‐up assessments. Our search yielded 23 eligible studies, including 5,298 participants. We found a small to medium favorable effect on distress indicators (SMD=–0.45, 95% CI: –0.56 to –0.34) and a small beneficial effect on positive mental health outcomes (SMD=0.31, 95% CI: 0.14‐0.47), which both remained significant at follow‐up assessment and were robust in sensitivity analyses. However, our analyses pointed to substantial between‐study heterogeneity, which was only partially explained by moderators, and the certainty of evidence was very low across all outcomes. These results provide evidence for the effectiveness of PM+ and SbS in reducing distress indicators and promoting positive mental health in populations exposed to adversities, but a larger high‐quality evidence base is needed, as well as research on participant‐level moderators of the effects of these interventions, their suitability for stepped‐care programs, and their cost‐effectiveness.