Criterion A2 according to the Diagnostic and Statistical Manual of Mental Disorders (4th ed.; DSM-IV; American Psychiatric Association [APA], 1994) for posttraumatic stress disorder (PTSD) aims to assess the individual's subjective appraisal of an event, but it has been claimed that it might not be sufficiently specific for diagnostic purposes. We analyse the contribution of Criterion A2 and DSM-IV criteria to detect PTSD for the most distressing life events experienced by our subjects. Young adults (N = 1,033) reported their most distressing life events, together with PTSD criteria (Criteria A2, B, C, D, E, and F). PTSD prevalence and criterion specificity and agreement with probable diagnoses were estimated. Our results indicate 80.30% of the individuals experienced traumatic events and met one or more PTSD criteria; 13.22% cases received a positive diagnosis of PTSD. Criterion A2 showed poor agreement with the final probable PTSD diagnosis (correlation with PTSD .13, specificity = .10); excluding it from PTSD diagnosis did not the change the estimated disorder prevalence significantly. Based on these findings it appears that Criterion A2 is scarcely specific and provides little information to confirm a probable PTSD case.