Prevalence of torture and other warrelated traumatic events in forced migrants: A systematic review

To describe and appraise the research literature reporting prevalence of torture and/or war-related potentially traumatic experiences (PTEs) in adult forced migrants living in high-income countries.

A search for peer-reviewed articles in English was conducted in PubMed, Web of Science, PILOTS, key journals, and reference lists. Studies based on clinical samples and samples where less than half of participants were forced migrants were excluded. Data was extracted and a methodological quality appraisal was performed.

A total of 3,470 titles and abstracts were retrieved and screened. Of these, 198 were retrieved in full-text. Forty-one articles fulfilled inclusion criteria and the total number of study participants was 12,020 (median 170). A majority focused on specific ethnic groups or nationalities, Southeast Asian, Middle Eastern and Balkan being the most frequent. Reported prevalence rates of torture ranged between one and 76 % (median 27 %). Almost all participants across all studies had experienced some kind of war-related PTE.

Reported prevalence rates of torture and war-related PTEs vary between groups of forced migrants. Trauma history was often studied as a background variable in relation to mental health. The heterogeneity of data, as well as the methodological challenges in reaching forced migrants and defining and measuring traumatic experiences, prevent generalisation concerning trauma history across groups.