title: A test of the Interpersonal Theory of Suicide in a large community-based cohort.
abstract: BACKGROUND
  Joiner's Interpersonal Theory of Suicide (Van Orden et al., 2010; Joiner, 2005) predicts that suicide ideation is strongest in those experiencing both high perceived burdensomeness and thwarted belongingness, and that the combination of suicide ideation and acquired capability for suicide is critical in the development of suicide plans and attempts. However, few datasets exist which allow the examination of these predictions. The present study aimed to test predictions from the model in a population-based cohort.
  
  
  METHODS
  a survey was completed by 6133 participants from the PATH Through Life Project. Scales measuring perceived burdensomeness, thwarted belongingness, hopelessness, capability to self-injure, ideation, plans and attempts were developed using existing items. Regression models were used to predict the outcomes of ideation and of plans/attempts.
  
  
  RESULTS
  consistent with the Interpersonal Theory, interactions were found between perceived burdensomeness and thwarted belongingness predicting ideation, and interactions of capability and ideation for plans/attempts. However, some predictions of the theory were not fulfilled. Nevertheless, the Interpersonal Theory explained more variance than epidemiological models using mental disorders as predictors. Age differences were evident, with models of older cohorts accounting for less variance. Gender models suggested thwarted belongingness was a stronger predictor of ideation in males than females.
  
  
  CONCLUSIONS
  while the fit of the factors assessing the Interpersonal Theory was adequate, the findings will need to be confirmed using previously developed scales of these constructs.
  
  
  CONCLUSIONS
  predictive models of suicide need to take into account multiple risk factors, gender differences and changes in associations over the life span.
authors.affiliation: Black Dog Institute, The University of New South Wales, Randwick, NSW 2033, Australia. h.christensen@blackdog.org.au
authors.forename: Helen
authors.initials: H
authors.lastname: Christensen
authors.forename: Philip J
authors.initials: PJ
authors.lastname: Batterham
authors.forename: Andrea
authors.initials: A
authors.lastname: Soubelet
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Mackinnon
mesh_terms: D000223:Adaptation, Psychological; D000328:Adult; D000367:Age Factors; D000368:Aged; D020958:Australian Capital Territory; D015986:Confounding Factors, Epidemiologic; D004243:Divorce / Q000523:psychology; D004644:Emotions; D005260:Female; D006801:Humans; D007398:Interpersonal Relations; D008016:Life Change Events; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D011340:Problem Solving; D012307:Risk Factors; D012494:Sampling Studies; D016728:Self-Injurious Behavior / Q000523:psychology; D012737:Sex Factors; D059020:Suicidal Ideation; D013405:Suicide / Q000523:psychology*; D013406:Suicide, Attempted / Q000523:psychology