Nonsuicidal self-injury characteristics: A mixed methods analysis of differences between veterans and civilians

Nonsuicidal self-injury (NSSI) is a well-established risk factor for suicidal behavior, with certain NSSI characteristics being associated with increased risk. In the United States (U.S.), the veteran suicide rate is elevated, though lifetime prevalence rates of NSSI appear similar between veterans and civilians. There is limited research that directly compares veterans and civilians across multiple NSSI characteristics to examine between-group differences in NSSI behavior and provide important context for the application of NSSI research with the veteran population. This study examined differences between U.S. veterans and civilians with a history of suicidal ideation across several NSSI characteristics, including method, severity, age of onset, shame, distress, and reason for initial NSSI engagement. A sample of 527 veterans and civilians completed measures of direct and indirect NSSI behaviors along with supplemental questions designed to further assess endorsed NSSI behaviors. Additionally, respondents provided written responses to an open-ended question about their reasons for initial engagement in NSSI, which were coded for post-hoc analysis. Chi-square difference tests and t-tests were conducted, revealing significant group differences between veterans and civilians in NSSI method, lifetime versatility, age of onset, age at last occurrence, and reasons for initial engagement. No significant differences were found in NSSI frequency, severity, shame, or distress. These findings provide valuable information on similarities and differences in NSSI behavior characteristics between U.S. veterans and civilians with lifetime suicidal ideation to inform future research and the assessment of NSSI in these populations.