Psychometric Properties of the Embedded and Stand-Alone Versions of the MMPI-2 Keane PTSD Scale

Abstract

This study investigated the comparability of the embedded and stand-alone versions of the Keane Posttraumatic Stress Disorder scale (PK scale) of the Minnesota Multiphasic Personality Inventory-2 (MMPI-2). Participants were 123 Vietnam theater veterans, 68 of whom (55%) were diagnosed with war zone-related posttraumatic stress disorder (PTSD). In separate testing sessions scheduled two to three days apart, all participants first completed the full MMPI-2 followed by the 46 PK scale items administered in a stand-alone format. Sixty participants completed the stand-alone version again in a third session. In addition, all participants were administered the Structured Clinical Interview for DSM-III-R (SCID), including the PTSD module, and completed a number of other questionnaire measures of combat exposure and PTSD. Results indicated that the embedded and stand-alone versions of the MMPI-2 PK scale are quite comparable in terms of mean scores, internal consistency, convergent validity, and diagnostic utility. Use of the standalone version is indicated for assessment applications in which the full MMPI-2 cannot be administered.