Convergent validity of measures of PTSD in an elderly population of former prisoners of war

Thirty former World War II Far East prisoners of war were assessed with a structured clinical interview for PTSD based on DSM‐III‐R criteria and the results compared with the self‐report measures. Thirty per cent of the subjects fulfilled a DSM‐III‐R diagnosis of PTSD and 90% complained of at least one post traumatic intrusive or avoidant symptom. The Mississippi scale was the most accurate measure of PTSD severity (r = 0.81) and the MMPI‐PTSD subscale was the most efficient dichotomous measure of PTSD (sensitivity = 0.89 and specificity = 0.62). The avoidance subscale of the impact of event scale did not discriminate avoidant symptoms from those of intrusion. Self‐report scales for chronic PTSD used in the elderly should be interpreted with caution and require further evaluation of their validity.