Global prevalence of self-harm during the COVID-19 pandemic: A systematic review and meta-analysis

Abstract Background: Little is know about the prevalence of self-harm worldwide during the COVID-19. This study aimed to estimate the prevalence of self-harm worldwide during COVID-19. An attempt was also performed to explore the causes of heterogeneity by analyzing the characteristics in the included studies. Methods: By using permutations of COVID-19, self-harm or relevant search terms, we searched the following electronic databases for studies prior to January 2022: Web of Science, PubMed, MEDLINE, Embase, PsycINFO, Cochrane Database of Systematic Reviews, China National Knowledge Infrastructure (CNKI), Wanfang Database and systematically reviewed the evidence according to MOOSE guidelines. We employed the Cochran’s chi-squared test (Cochran’s Q), I2 test and subgroup analysis to assess and address the heterogeneity. Funnel plots, Egger’s and Begg’s tests were utilized to evaluate publication bias, while trim-and-fill method was done to identify possible asymmetry and determine the robustness of the results. Results: 16 studies that met the inclusion and exclusion criteria were identified, with the sample sizes ranging from 228 to 49,227. The methodological quality of the included studies were mostly at the medium level. By using random effect model, the pooled prevalence of self-harm was 15.8% (95%CI 13.3-18.3). Based on subgroup analysis, the following characteristics of the included studies reported a higher prevalence of self-harm: studies conducted in Asia or prior to July 2020, cross-sectional studies, samples recruited in hospital or school, adolescents, female, the purpose of self-harm (NSSI), mental symptoms and restriction experiences. Conclusions: We provide first meta-analytic estimated prevalence of self-harm based on large sample from different countries and populations. The incidence of self-harm during COVID-19 was not encouraging and requires attention and intervention. The obvious heterogeneity between included studies requires more high-quality and prospective studies in the future to obtain a more accurate prevalence of self-harm. In addition, this study also provides new directions for future research, including the identification of high-risk groups for self-harm, the formulation and implementation of prevention and intervention programs, and the long-term impact of COVID-19 on self-harm, etc.