Should A2 be a diagnostic requirement for posttraumatic stress disorder in DSM-V?

The requirement that trauma survivors experience fear, helplessness or horror (Criterion A2) as a part of their posttraumatic stress disorder (PTSD) diagnosis was introduced into DSM-IV. The imminent re-definition of PTSD in DSM-V highlights the need for empirical studies to validate the utility of the A2 requirement. We aimed to identify (i) how often A2 was associated with PTSD (B-F criteria) at 3 months after trauma and (ii) what was the peritraumatic emotional experience for those who met PTSD criteria but were A2 negative. In a prospective design cohort study we assessed the peritraumatic emotional experience of 535 injury patients in four Australian hospitals. These patients were followed up 3 months later and assessed for PTSD using a structured clinical interview. The majority of those who developed PTSD (B-F criterion) at 3 months met A2 criteria. A substantial minority, however (23%), did not meet A2 criteria. Those PTSD patients who were A2 negative fell into three groups: (i) those who experienced subthreshold levels of A2; (ii) those who experienced intense peritrauma emotional responses other than fear, helplessness or horror; and (iii) those who were amnesic to their peritrauma emotional experience. These findings do not support the inclusion of A2 as diagnostic requirement for DSM-V.