An MMPI-2 infrequent response scale for use with psychopathological populations: The Infrequency-Psychopathology Scale, F(p).

This article describes the development and initial validation of a new Minnesota Multiphasic Personality Inventory—2 (MMPI-2; J. N. Butcher, W. G. Dahlstrom, J. R. Graham, A. Tellegen, & B. Kaemmer, 1989) scale designed to detect infrequent responding in settings characterized by relatively high base rates of psychopathology and psychological distress. The Infrequency-Psychopathology Scale, F(p), was developed by identifying a set of 27 MMPI-2 items answered infrequently by both inpatients and the MMPI-2 normative sample. The new scale's construct validity was examined through tests of a series of hypotheses derived from an analysis of the reasons for elevated Infrequency (F) and Infrequency-Back (Fb) scores in inpatient settings. The F(p) scale's incremental validity was explored by comparing its performance to that of the F scale. The results of this study suggest that F(p) may be used as an adjunct to F in settings characterized by relatively high base rates of psychopathology and psychological distress. An important feature contributing to the clinical usefulness of the Minnesota Multiphasic Personality Inventory—2 (MMPI-2; Butcher, Dahlstrom, Graham, Tellegen, & Kaemmer, 1989) is the availability of scales that assess the validity of individual test protocols. The importance of appraising the validity of individual test scores was recognized by Hathaway and McKinley (1943), who included two validity scales, Lie (L) and Infrequency (F) in the original version of the MMPI. The F scale was developed as an infrequent-response indicator by identifying 64 items that were answered infrequently in the