Developmental trajectories of non-suicidal self-injury in adolescence: The effect of social support and socioeconomic status.

Background: Non-suicidal self-injury (NSSI) in early adolescence has been amply documented. However, there has been little research on the progression of NSSI over time. Most studies have focused on the risk factors for NSSI, with less attention devoted to understanding the role of protective factors. This paper aimed to expand existing knowledge about the development of NSSI, with an emphasis on the impacts of protective factors such as social support and socioeconomic status (SES).

Methods: A total of 436 adolescents completed self-report surveys that addressed social support including friend, family, and teacher support, objective and subjective SES, and NSSI at three different points in time for 2 years.

Results: Latent growth curve analyses revealed that NSSI increased across early adolescence to mid-adolescence. Support from friends and family negatively predicted adolescents' initial NSSI level. Furthermore, subjective SES negatively predicted the rate of NSSI.

Conclusions: These findings contribute to an understanding of the influences of both social support and SES on NSSI over time. NSSI interventions and education should include considerations of both the value of support from friends and family as well as subjective SES.