Rates of nonsuicidal self-injury in youth: age, sex, and behavioral methods in a community sample.

OBJECTIVE The goal was to assess the rate and behavioral methods of nonsuicidal self-injury (NSSI) in a community sample of youth and examine effects of age and sex. METHODS Youth in the third, sixth, and ninth grades (ages 7-16) at schools in the community were invited to participate in a laboratory study. A total of 665 youth (of 1108 contacted; 60% participation rate) were interviewed about NSSI over their lifetime via the Self-Injurious Thoughts and Behaviors Interview. RESULTS Overall, 53 (8.0%) of the 665 youth reported engaging in NSSI; 9.0% of girls and 6.7% of boys reported NSSI engagement; 7.6% of third-graders, 4.0% of sixth-graders, and 12.7% of ninth-graders reported NSSI engagement. There was a significant grade by gender interaction; girls in the ninth grade (19%) reported significantly greater rates of NSSI than ninth-grade boys (5%). Behavioral methods of NSSI differed by gender. Girls reported cutting and carving skin most often, whereas boys reported hitting themselves most often. Finally, 1.5% of youth met some criteria for the proposed fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) diagnosis of NSSI. CONCLUSIONS Children and adolescents engage in NSSI. Ninth-grade girls seem most at risk, as they engage in NSSI at 3 times the rate of boys. Behavioral methods of NSSI also vary by grade and gender. As possible inclusion of an NSSI diagnosis in the fifth edition of the DSM-5 draws near, it is essential to better understand NSSI engagement across development and gender.