A New Measure of Pain Catastrophizing: Validity and Reliability of the Concerns About Pain Scale in Turkish Fibromyalgia Patients

Background/Aims: Fibromyalgia (FM) syndrome is characterized by chronic widespread pain, sleep disturbances, and psychiatric symptoms. Pain catastrophizing plays an important role in FM and negatively affects quality of life. The University of Washington Concerns About Pain Scale (UW-CAP) was developed using modern psychometric methods. This study aimed to evaluate the validity and reliability of the Turkish version of the UW-CAP (UWCAP6-TR) in patients with FM.

Materials and Methods: The study was conducted according to the COSMIN guidelines and included 50 patients diagnosed with FM (44 female, 6 male). The patients were assessed with the UWCAP6-TR and the Pain Catastrophizing Scale (PCS). Cronbach’s alpha coefficient was used to evaluate internal consistency; intraclass correlation coefficient (ICC) was used for test–retest reliability. Construct validity was evaluated using confirmatory factor analysis and correlation analysis with the PCS. The unidimensionality of the scale was examined by Rasch analysis.

Results: The UWCAP6-TR had a Cronbach’s α coefficient of 0.89 and excellent test–retest reliability (ICC = 0.95). Item-total correlations ranged from 0.58 to 0.84. Confirmatory factor analysis supported the original scale structure (comparative fit index = 0.98, root mean square error of approximation = 0.08), and there was moderate correlation with the PCS (r = 0.42). Rasch analysis confirmed that the scale is unidimensional with no local dependence problem.

Conclusion: The UWCAP6-TR is a valid, reliable, and useful scale for assessing the pain-related concerns of FM patients. With its short form and modern psychometric structure, it is suitable for use in both clinical and research settings. Future studies can investigate the sensitivity of the scale by enlarging the sample.

Cite this article as: Gökpınar HH, Saraçoğlu İ, Aksoy CC, Özdemir MF. A new measure of pain catastrophizing: Validity and reliability of the concerns about pain scale in Turkish fibromyalgia patients. ArchRheumatol. Published online July 10, 2026. doi: 10.5152/ArchRheumatol.2026.26293.