Chronic pain acceptance questionnaire: confirmatory factor analysis, reliability, and validity in Italian subjects with chronic low back pain.
STUDY DESIGN
Cross-sectional evaluation of the psychometric properties of a translated questionnaire.


OBJECTIVE
To validate the Italian version of the Chronic Pain Acceptance Questionnaire (CPAQ) to allow its use with Italian-speaking patients with chronic low back pain (LBP).


SUMMARY OF BACKGROUND DATA
Growing attention is being given to cognitive-behavioral measures to improve interventions for LBP. The CPAQ has never been validated in Italian subjects with chronic LBP.


METHODS
The psychometric testing included confirmatory factor analysis, reliability by internal consistency (Cronbach α), test-retest reliability (intraclass correlation coefficient), sensitivity to change by calculating the smallest detectable change, and construct validity by comparing CPAQ with a pain numerical rating scale, the Roland-Morris Disability Questionnaire Scale, the Hospital Anxiety and Depression Scale, the Pain Catastrophizing Scale, and the Tampa Scale of Kinesiophobia (Pearson correlations). Hierarchical multiple regression analyses were computed to further investigate construct validity of the CPAQ subscales.


RESULTS
The questionnaire was administered to 142 subjects with chronic LBP. Factor analysis confirmed a 2-factor (viz., Activities Engagement and Pain Willingness) 20-item solution, achieving a good data-model fit. Internal consistency (α = 0.88) and test-retest reliability (intraclass correlation coefficient = 0.86) were good. The smallest detectable change was 22. Construct validity showed a moderate correlation between the CPAQ and numerical rating scale (r = -0.485), Roland-Morris Disability Questionnaire Scale (r = -0.594), and Tampa Scale of Kinesiophobia (r = -0.595), and a close correlation with Hospital Anxiety and Depression Scale (r = -0.610 for the Anxiety score and r = -0.659 for the Depression score) and Pain Catastrophizing Scale (r = -0.658). The standardized regression coefficients for Activity Engagement were significant in all of the equations, and those for Pain Willingness were significant in the anxiety, depression, and disability equations.


CONCLUSION
The Italian CPAQ had a good factorial structure and psychometric properties that replicated the results of other versions. Its use is recommended for clinical and research purposes.


LEVEL OF EVIDENCE
2.