All respondents endorsing one or more traumatic events in the trauma checklist administered at Wave 4 (n=1684; 44.5% of the sample) were asked which of the events they experienced was the most disturbing. They were then asked if they had experienced ‘intense fear, helplessness, or horror ’ following that event (DSM-IV Criterion A). For those who responded ‘yes’, this became the index event for which PTSD symptoms were assessed. For Criteria B, C and D, diagnostic questions were administered only if the preceding criterion was met. Criterion B was met if 1 or more of the five possible re-experiencing symptoms were endorsed. Meeting Criterion C required endorsement of three or more of the seven possible avoidance symptoms. Criterion D was met if two or more of the five arousal symptoms were endorsed. A diagnosis of PTSD was given if Criteria A–D were met and respondents reported clinically significant distress or impairment and persistence of symptoms for ≥1 month. The prevalence of PTSD in the sample was 3.7% (n=138). As a PTSD diagnosis is contingent on trauma exposure, participants who did not endorse any traumatic experiences were coded as missing for PTSD.
