The Relationship Between Anger and Nonsuicidal Self‐Injury: A Meta‐Analysis

INTRO: Associations of negative affect and nonsuicidal self-injury (NSSI) are well-characterized. However, relationships between discrete negative emotions and NSSI are less well understood. An association between anger and NSSI is supported by contemporary models and growing evidence from studies across diverse populations. METHODS: The goal of this meta-analysis was to systematically review the literature and to calculate the effect size of the relationship between NSSI and anger. RESULTS: The relationship between NSSI and anger constructs was examined with data from 25 studies (total N = 9148). Results of the meta-analysis showed an overall moderate association between NSSI and anger (pooled Hedges' g = 0.55) based on 31 individual effect sizes. There were no significant differences in effect size estimates across anger constructs. There were no significant moderators of the relationship between NSSI and anger. DISCUSSION: Findings highlight the important role of the discrete emotion of anger in NSSI among adults. Findings may inform clinical recommendations such as the assessment for potential NSSI when individuals present with anger. Additionally, anger is likely related to the functions of NSSI and may play a role in maintaining this behavior. CONCLUSION: Future research is needed to examine the relationship between anger and NSSI utilizing longitudinal designs.