title: Implicit cognition about self-injury predicts actual self-injurious behavior: results from a longitudinal study of adolescents.
abstract: The implicit association hypothesis of nonsuicidal self-injury (NSSI) proposes that individuals who engage in self-injury develop, over time, strong associations between themselves and NSSI, and their identification with this behavior guides their future selection of NSSI to cope. Prior research has established a relationship between implicit NSSI associations (using an Implicit Association Test for Self-Injury) and engagement in NSSI. However, previous studies have been small and cross-sectional, and thus underpowered to examine the nature of this association and the extent to which implicit associations predict the persistence of NSSI.
  
  
  
  This study builds on previous research in a prospective, longitudinal examination of implicit self-identification with NSSI in a large sample of middle school students. NSSI behavior and implicit NSSI associations were assessed annually in school at three time points.
  
  
  
  Adolescents who engaged in NSSI exhibited stronger implicit self-identification with NSSI than adolescents who did not engage in NSSI. Moreover, implicit NSSI identification was stronger among adolescents who engaged in cutting, frequent NSSI, and recent NSSI. A reciprocal association was observed between NSSI frequency and implicit NSSI identification over 1 year. Notably, implicit NSSI identification uniquely and prospectively predicted engagement in NSSI over the subsequent year.
  
  
  
  Implicit self-identification with NSSI may track both trait- and state-related changes in the behavior and, importantly, may help predict continued engagement in NSSI.
authors.affiliation: Clinical and Social Sciences in Psychology, University of Rochester, Rochester, NY, USA.
authors.forename: Catherine R
authors.initials: CR
authors.lastname: Glenn
authors.affiliation: Department of Psychology, Harvard University, Cambridge, MA, USA.
authors.forename: Evan M
authors.initials: EM
authors.lastname: Kleiman
authors.affiliation: Teachers College, Columbia University, New York, NY, USA.
authors.forename: Christine B
authors.initials: CB
authors.lastname: Cha
authors.affiliation: Department of Psychology, Harvard University, Cambridge, MA, USA.
authors.forename: Matthew K
authors.initials: MK
authors.lastname: Nock
authors.affiliation: Department of Psychology, University of North Carolina, Chapel Hill, NC, USA.
authors.forename: Mitchell J
authors.initials: MJ
authors.lastname: Prinstein
mesh_terms: D000293:Adolescent; D000294:Adolescent Behavior / Q000523:psychology*; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D012649:Self Concept; D016728:Self-Injurious Behavior / Q000523:psychology*
keywords: Self-injury; adolescence; assessment; longitudinal studies; self-harm