title: Post-traumatic stress disorder symptoms form a traumatic and non-traumatic stress response dimension.
abstract: OBJECTIVE
  This study aims to determine whether symptoms of post-traumatic stress disorder (PTSD) form a latent dimension reflecting responsivity to life events and whether PTSD symptoms are specific to traumatic life events.
  
  
  METHODS
  A 30-year longitudinal study of a general population sample of 987 individuals were assessed for PTSD symptoms, exposure to adverse life events, and a variety of psychosocial measures. PTSD symptoms were tested using a confirmatory factor model and a range of fitted models were used to identify significant predictors of latent PTSD symptoms.
  
  
  RESULTS
  The rate of DSM IV PTSD was 1.9%. However, subjects reported high rates of at least one significant traumatic or negative life event and PTSD symptoms. The PTSD symptoms conformed well to a single latent factor. There were strong linear associations between severity of PTSD symptoms and exposure to traumatic and non-traumatic life events. Factors contributing to latent PTSD symptoms were gender, childhood anxiety, neuroticism, self-esteem, and quality of parental care.
  
  
  CONCLUSIONS
  Criteria for PTSD form an underlying dimension reflecting the individual's level of responsivity to traumatic and non-traumatic stressful life events. PTSD symptoms form a continuum of severity with minor stress symptoms at one end and severe PTSD at the other.
authors.affiliation: Department of Psychological Medicine, University of Otago, Christchurch, New Zealand. roger.mulder@otago.ac.nz
authors.forename: Roger
authors.initials: R
authors.lastname: Mulder
authors.forename: David
authors.initials: D
authors.lastname: Fergusson
authors.forename: John
authors.initials: J
authors.lastname: Horwood
mesh_terms: D008016:Life Change Events; D008137:Longitudinal Studies; D008960:Models, Psychological; D009520:New Zealand / Q000453:epidemiology; D012307:Risk Factors; D013313:Stress Disorders, Post-Traumatic / Q000175:diagnosis* / Q000453:epidemiology; D063189:Symptom Assessment / Q000523:psychology*
keywords: Population study; post-traumatic stress disorder; stress response