Characteristics of chronic pain patients: factor analysis of the MMPI-2.

The Minnesota Multiphasic Personality Inventory (MMPI) has been used extensively in the assessment of chronic pain patients. More recent studies using cluster-analytic techniques, investigation of sub-scales, and factor analysis have refined its usefulness. The present study factor-analyzed MMPI-2 data from a sample of 114 chronic pain patients from two different treatment programs. MMPI-2 t scores for the validity and clinical scales, as well as the Harris and Lingoes sub-scales for scales 1, 2 and 3, were used in the analysis. Four interpretable factors emerged and were labeled 'Psychological Dysfunction', 'Interpersonal Isolation', 'Psychomotor Retardation', and 'Physical Dysfunction' to reflect factor loadings. Results are discussed in terms of demonstrating support for using the MMPI-2 factors to refine the assessment of chronic pain patient characteristics.