To the Editor: We read with interest the recent article by Meaghan L. O’Donnell, Ph.D., et al. (1) that reported psychopathology after traumatic injury and found a low rate of acute stress disorder (1%). Our group has also been interested in psychiatric disorders related to traumatic injury, and we appreciate the authors citing our study (2). We believe that the report of Dr. O’Donnell et al. of significant rates of posttraumatic stress disorder (PTSD) and depression after injury and the discussion of potential confounders to the assessment of dissociation are informative contributions to the literature. We are concerned, however, that the low rate of acute stress disorder was a consequence of unduly restrictive diagnostic procedures.

Dr. O’Donnell et al. assessed participants an average of 8 days after injury. In order to determine acute stress disorder status, they modified questions on the Clinician-Administered PTSD Scale to ask about dissociative symptoms only since cessation of intravenous narcotic analgesia. Because of concerns regarding the contributions of narcotics, intoxication, and traumatic brain injury, the investigators did not include dissociative symptoms experienced at the scene of injury.

In our study, we assessed PTSD symptoms and, in most cases, continuing dissociative symptoms with the Clinician-Administered PTSD Scale. Dissociative symptoms at or near the time of injury were assessed with the Peritraumatic Dissociation Scale (3). We reduced some of the potential confounds that Dr. O’Donnell et al. were concerned about by excluding individuals who were intoxicated at the time of injury or had signs of traumatic brain injury. Interviews were conducted within a time frame that was similar to that of Dr. O’Donnell et al. While most of our subjects did receive intravenous narcotics during rescue and/or early during their admission, this did not lead to high rates of endorsement of dissociative criteria for acute stress disorder (16% met the criteria). Of the nine subjects we diagnosed with acute stress disorder in whom dissociation was assessed with the Peritraumatic Dissociation Scale and the Clinician-Administered PTSD Scale, only one would have met the criteria for acute stress disorder based solely on continuing dissociation assessed with the Clinician-Administered PTSD Scale. Therefore, it appears that peritraumatic dissociation does not necessarily persist into the first or second week after trauma. The rationale for emphasizing dissociation among the diagnostic criteria for acute stress disorder was based on studies of initial reactions to trauma (4). Lack of inclusion of information about the peritraumatic period would likely lead to underdiagnosis of acute stress disorder.