The STRENGTHS (Scaling up psychological interventions with Syrian Refugees) project aims to evaluate the effectiveness, cost-effectiveness, implementation and scalability of low-intensity psychological interventions developed by the WHO (Problem Management Plus, Step-By-Step). To achieve that, five pilot and seven fully powered Randomized Controlled Trials (RCTs) were conducted in seven countries: Jordan (camp setting, group format), Turkey (community setting, group format), Switzerland (community setting individual format), the Netherlands (community setting individual format), Germany (online), Sweden (online) and Egypt (online).

The RCTs include Syrian refugees of 18 years and above with elevated psychological distress (Kessler Psychological Distress Scale (K10>15)) and impaired daily functioning (WHO Disability Assessment Schedule 2.0 (WHODAS 2.0>16)). Participants are randomised into the intervention or care as usual control group, and complete follow-up assessments at 1-week, 3-month and 12-month follow-up. Primary outcomes are symptoms of depression and anxiety (25-item Hopkins Symptom Checklist). Secondary outcomes include daily functioning (WHODAS 2.0), PTSD symptoms (PTSD Checklist for DSM-5) and self-identified problems (PSYCHLOPS). The data from all the trials are combined and harmonised to be analysed with an one-stage IPD meta-analysis using linear mixed models. Quality of evidence will be assessed using the GRADE approach, and the economic evaluation approach will be assessed using the CHEC-list.

The data are available upon reasonable motivated request (to be approved by the General Assembly of the project).