PTSD prevalence and symptom structure of DSM-5 criteria in adolescents and young adults surviving the 2011 shooting in Norway

BackgroundDiagnostic criteria for Posttraumatic Stress Disorder (PTSD) have been revised for DSM-5. Two key changes include alteration of the clustering of PTSD symptoms and new PTSD symptom criteria related to negative alterations in cognition and mood. In this study, we empirically investigated these changes.MethodsWe interviewed 325 adolescents and young adults who survived the 2011 youth camp shooting at Utøya Island, Norway. The UCLA PTSD Reaction Index for DSM-IV was used to assess symptoms of PTSD. In addition, 11 questions were added to assess the four new symptom criteria within the new DSM-5 symptom categories.ResultsPTSD prevalence did not differ significantly whether DSM-IV (11.1%) or DSM-5 (11.7%) criteria were used and the Cohen׳s Kappa for consistency between the diagnoses was 0.061. Confirmatory factor analyses showed that the four-factor structure of the DSM-5 fit the data adequately according to the conceptual model outlined.LimitationsThe homogeneity of this sample of highly exposed subjects may preclude generalization to less severely exposed groups. Also, we did not assess criterion G in regard to symptoms causing clinically significant distress and functional impairment.ConclusionThe prevalence of PTSD was quite similar regardless of diagnostic system. The relatively low concordance between the diagnoses has implications for eligibility for a diagnosis of PTSD.