343: Personality Characteristics and Classification of Chronic Pain Patients Assessed Using the MMPI-3

Topic: Clinical Science
Subtopic: Non-specific to any diagnosis, Psychology

Background and Aims: The MMPI personality test and its revised version, the MMPI-2, reported the Conversion V pattern as a characteristic of chronic pain patients. However, due to significant overlap between scales in these versions, the MMPI-2-RF separated the common factor as demoralization and created 10 Restructured Clinical Scales. Assessments of psychosocial risk using these scales have been widely reported. The MMPI-3, released in 2020, added new scale groups measuring internalizing, externalizing, and somatization. The purpose of this study is to investigate the personality characteristics of chronic pain patients using the MMPI-3 and to clarify the relationship with other pain-related indicators.

Methods: The participants were chronic pain patients who produced valid MMPI-3 profiles and completed pain-related questionnaires (SF-MPQ, VAS, PCS, PVAQ, CPAQ, HADS, PDAS, EQ5D-5L) with no missing data. The proportion with T-scores ≥ 65 on four MMPI-3 Specific Problems domains: (Somatic/Cognitive; SOM/COG, Internalizing; INTL, Externalizing; EXTL, Interpersonal; IPR) was calculated. The scales within each domain were converted into a single factor score through factor analysis. Cluster analysis was conducted on standardized domain factor scores, and questionnaire scores were compared across clusters using one-way ANOVA with Tukey’s HSD.

Results: Ninety-one participants (50.2 ± 16.1 years; 33 men) met the inclusion criteria. The proportion with T-scores ≥ 65 was 35.7% (SOM/COG), 17.9% (INTL), 11.2% (EXTL), and 10.6% (IPR). Ward’s method suggested three clusters, and k-means assigned individuals. Mean (SOM/COG/INTL/EXTL/IPR) scores were: C1, 0.84/0.88/0.34/1.35; C2, −0.55/−0.67/−0.67/−0.38; and C3, 0.43/0.67/1.28/−0.55. C1 showed lower VAS, C2 lower HADS-D, and C3 higher PCS with lower CPAQ. There were no significant differences in the other questionnaires.

Conclusions: Most frequent MMPI-3 domain elevations in chronic pain were observed in Somatic/Cognitive and Internalizing, reflecting physical symptom burden and cognitive dysfunction. Cluster analysis of the Specific Problems Scales identified three clinically interpretable subtypes: C1 (internalizing, low VAS), C2 (low burden across all four domains with minimal depressive tendencies), and C3 (externalizing, characterized by catastrophizing and low pain acceptance). Subtype differences emerged despite similar pain descriptions, hypervigilance, functional impairment, and quality of life, suggesting that MMPI-3 subtyping captures coping styles and emotional processes rather than pain quality or intensity. Longitudinal replication and validation of outcomes are needed.

References: ・Ben-Porath YS, Tellegen A. MMPI-3 Technical Manual. Pearson 2020.
・Mickens LD, Nghiem DM, Wygant DB, Umlauf RL, Marek RJ. Validity of the Somatic Complaints Scales of the MMPI-2-RF in an outpatient chronic pain clinic. Journal of Clinical Psychology in Medical Settings 2021;28:789–797.
・Block AR, Ben-Porath YS, Marek RJ. Psychological risk factors for poor outcome of spine surgery and spinal cord stimulator implant: a review of the literature and their assessment with the MMPI-2-RF. The Clinical Neuropsychologist 2013;27:81–107.

Presenting Author: Yasuyuki Mizuno
Submitting Author: Yasuyuki Mizuno

Senior Author: Yasuyuki Mizuno

IASP 2026 Global Year theme of Neuropathic Pain: No