Developmental Trajectories of Non-Suicidal Self-Injury (Disorder) throughout Adolescence and Emerging Adulthood: An Integrative Model of Personality and Identity in Community and Clinical Samples.
Non-suicidal self-injury (NSSI) is defined as ‘the direct, deliberate destruction of one’s own body tissue without suicidal intent’ and constitutes a significant public health problem. Common NSSI methods include cutting, burning, and hitting oneself. Research suggests that the occurrence of NSSI is still increasing, especially among adolescents and young adults. NSSI is associated with negative mental health outcomes, including anxiety, depression, and suicide. These findings underscore the need for a better understanding of NSSI and how it develops over time. Despite the high prevalence of NSSI in adolescents and young adults, few studies have examined developmental trajectories of NSSI through adolescence and the transition to adulthood. Additionally, although clinicians often link NSSI to problems with identity formation, only a few studies to date have investigated how NSSI relates to this key normative developmental task of adolescence and emerging adulthood. In the present project, we expand the existing knowledge about the development of NSSI and the relationship between NSSI and identity formation throughout adolescence and emerging adulthood in community and clinical samples (i.e., eating disorders). An integrative model is forwarded in which the combined impact of core personality traits and identity formation on the emergence and development of NSSI will be examined.