Development and psychometric evaluation of the Polish version of the Chronic Pain Acceptance Questionnaire (CPAQ)

Chronic pain remains a significant health concern, particularly among older adults. Pain acceptance - engaging in valued activities despite pain without attempting to control or avoid it - is thought to buffer against the negative psychosocial impacts of chronic pain. The present study aimed to adapt to Polish and evaluate the psychometric properties of a widely used measure of pain acceptance, namely the Chronic Pain Acceptance Questionnaire (CPAQ). Two samples of individuals with chronic pain participated: an online sample (N = 418) and a hospital-recruited sample (N = 148). Confirmatory factor analyses assessed one-factor, two-correlated-factor, and two-orthogonal-factor models for both the original 20-item (CPAQ-20) and the short 8-item (CPAQ-8) versions. In both samples, the results consistently supported a two-factor correlated structure for the Polish CPAQ-8: Activity Engagement (AE) and Pain Willingness (PW). The CPAQ-20 did not show adequate fit. The CPAQ-8 demonstrated acceptable-to-good internal consistency (Cronbach's α = 0.63-0.78 total; 0.75-0.82 subscales) and moderate test-retest reliability (ICC = 0.57). The Minimal Detectable Change for the total score was 9.34 points. In the online sample, CPAQ-8 scores negatively correlated with pain anxiety, pain catastrophizing, anxiety, and depression. Across both samples, total CPAQ-8 and PW scores, but not AE, were negatively associated with pain. Participants reporting activity limitations scored significantly lower on CPAQ-8. Additionally, age was positively correlated with AE scores in both samples. Overall, the Polish CPAQ-8 exhibits good psychometric properties and is suitable for both research and clinical applications. Future studies should examine its longitudinal validity.