Fibromyalgia and chronic pain: Are there discriminating patterns by using the Minnesota Multiphasic Personality Inventory-2 (MMPI-2)?

The aim of this ex post fact study was to explore how the wide variety of somatic and psychopathological symptoms presented by fibromyalgia patients can be reflected in the Minnesota Multiphasic Personality Inventory-2 (MMPI-2) questionnaire. In addition, it was intended to discriminate patterns of responding between fibromyalgia patients, chronic pain patients (nonfibromyalgia-based) and healthy controls. Three subsamples were considered using an ex post facto design: fibromyalgia patients (n = 36), chronic pain patients (n = 44) and healthy controls (n = 34). The Spanish adaptation of the MMPI-2 was individually administered to all participants. Differential analyses indicated that a) fibromyalgia group scored higher in all MMPI- 2 validity and clinical scales, as compared to chronic pain and control groups; b) the fibromyalgia group MMPI-2 clinical profile is mainly oriented to the expression of a wide variety of somatic complaints, health problems, and physical malfunctioning; c) fibromyalgia group presented a pattern of overreporting responding which leads to hypothesize that some patients may reflect state of hypersensitivity and anxiety sensitivity, and others may reflect a pattern of seeking for psychological rewarding, maintaining a chronic sick role and chronic pain behaviours. Results indicate that MMPI-2 is a very useful psychometric tool to characterize a specific pattern of responding of fibromyalgia patients, and it is strongly recommended for bringing light to its clinical assessment.