Psychometric properties of the chronic pain acceptance questionnaire–20 in a Chilean chronic pain sample

Abstract

Background The construct of pain acceptance has gained increasing attention in the management of chronic pain, and the Chronic Pain Acceptance Questionnaire – 20 (CPAQ-20) is the primary instrument used to measure it. Objectives The objective of this study was to psychometrically evaluate the CPAQ-20 in a Chilean sample with chronic pain ( N = 401). Design and methods The factorial structure was analyzed using Confirmatory Factor Analysis (CFA), reliability with Cronbach's alpha, McDonald's Omega, and Test-retest. Concurrent validity was tested with SEM correlation and hierarchical regression analyses. Also, factorial invariance was assessed between different administration modalities (i.e., telephone survey vs. self-administration). Results/findings The two-factor structure—Activity Engagement (AE) and Pain Willingness (PW)—was confirmed. This model showed metric invariance across different administration modalities. The subscales exhibited good internal consistency ( α = .85 and 0.83, and both ω = 0.82) and moderate to good test-retest reliability (Intraclass Correlation Coefficient of 0.65 and 0.75). Pain interference, depression, and kinesiophobia showed significant associations with AE and PW. In the hierarchical regressions, the two subscales predicted unique variance of pain intensity, pain interference, pain catastrophizing, depressive, and anxiety symptoms. Only PW predicted kinesiophobia. Overall, the AE subscale showed larger coefficient magnitudes. Conclusions The results support the reliability and concurrent validity of the Chilean version of the CPAQ-20.