Our findings are consistent with prior research 9 and indicate that most participants who endorsed criterion A1 and met a probable PTSD diagnosis also endorsed criterion A2, though a small number did not. With regard to functional impairment, 7.8% of the sample met a probable PTSD diagnosis (including A1 and A2) and also indicated that their symptoms interfered in their life 'a moderate amount' or more (functional impairment score > 2) compared with 2.5% of participants with functional impairment scores greater than 3 ('quite a bit' or more). A total of 64.7% who endorsed Criterion A1 also endorsed A2. Restricting probable PTSD diagnosis to those meeting criterion A1 reduced probable PTSD rate to 16.4%, while restricting to those meeting A1 and A2 reduced probable PTSD rate to 12.6%. Rate of probable PTSD diagnoses disregarding A1 and A2 criteria was 18.6%. We examined how rates of probable PTSD changed based on different use of Criteria A1 and A2 and functional impairment. 8 Participants were also asked to indicate how much symptoms interfered with or caused difficulties in their life during the past week (functional impairment), rated on a 0 to 4 (not at all to extremely) scale. Probable PTSD diagnoses were assessed using the 10-item Trauma Screening Questionnaire (TSQ), a screening instrument with (yes/no) responses based on DSM-IV diagnostic criteria-defined PTSD symptoms experienced at least twice in the past week. 7 Participants were asked about lifetime history of potentially traumatic experiences and whether or not their response during these events involved intense fear, hopelessness, or horror. We examined rates of probable PTSD diagnoses as they relate to Criterion A and functional impairment in a cross-sectional sample of ethnically diverse college students from Hawaii (N = 614). 5 Some propose A2 should be eliminated because it lacks predictive power beyond Criterion A1. 3 Moreover, the VA has recently enacted policy changes that loosen disability criteria for establishing evidence of traumatic event exposure, while proponents of the 'bracket creep hypothesis' 4 express concern that the definition of trauma is too broad and further expansion will result in increased PTSD prevalence. Some have proposed dropping one or both components of PTSD Criterion A, 2 while others have suggested that Criterion A1 (the objective traumatic event) and A2 (a subjective response of 'fear, helplessness, or horror' to the event) be retained or reworded. 1 With the forthcoming publication of DSM-5 and recent changes in US Department of Veterans Affairs (VA) PTSD disability policies, such discussions are especially relevant regarding the definition of psychological trauma (Criterion A) and threshold for functional impairment.

To the Editor: Diagnostic criteria for posttraumatic stress disorder (PTSD) are often debated. Definition of Psychological Trauma and Threshold for Functional Impairment in PTSD

Trauma definition