Abstract
BACKGROUND: Non-suicidal self-injury (NSSI) in adolescents is a significant mental health problem around the world. Here, we performed a meta-analysis to systematically delineate the risk factors for NSSI. METHOD: We searched Medline, Embase, Web of Science and Cochrane for relevant articles and abstracts published prior to 12 November 2021. Pooled odds ratios (ORs) and 95% confident intervals (CIs) were used to assess various risk factors, and publication bias was assessed by Egger's test, the trim and fill method and meta-regression. This study is registered with PROSPERO, CRD42021265885. RESULTS: A total of 25 articles were eventually included in the analysis. Eighty risk factors were identified and classified into 7 categories: mental disorders (ORs, 1·89; 95% CI, 1·60-2·24), bullying (ORs, 1·98; 95% CI, 1·32-2·95), low health literacy (ORs, 2·20; 95% CI, 1·63-2·96), problem behaviours (ORs, 2·36; 95% CI, 2·00-2·77), adverse childhood experiences (ORs, 2·49; 95% CI, 1·85-3.34), physical symptoms (ORs, 2·85; 95% CI, 1·36-5·97) and the female gender (ORs, 2·89; 95% CI, 2·43-3·43). The range of heterogeneity (I(2)) was from 20·3% to 99·2%. CONCLUSION: This meta-analysis found that mental disorders, low health literacy, adverse childhood experiences, bullying, problem behaviours, the female gender and physical symptoms appear to be risk factors for NSSI.