Objective: This study was conducted to examine the psychometric properties of a Chinese translation of the Pain Catastrophizing Scale (HK-PCS).
Design/patients: Patients aged 18-79 years (N = 130) with chronic nonmalignant pain attending an outpatient multidisciplinary pain center in Hong Kong participated in this cross-sectional study.
Method: Subjects completed a set of health-related instruments: HK-PCS, Hospital Anxiety and Depression Scale, Roland Morris Disability Questionnaire, SF-36 Health Survey, and a general demographic questionnaire. Data were analyzed for the distribution, internal consistency, reliability, and construct validity.
Results: A satisfactory internal consistency was found (alpha = 0.927). The item-total correlation coefficients ranged from 0.575 to 0.777. The intraclass correlation coefficient was 0.969 for the total HK-PCS score, 0.956 for helplessness, 0.945 for magnification, and 0.910 for rumination. Confirmatory factor analysis verified a second-order factor structure with the comparative fit index = 1.00, root mean square error of approximation = 0.038, and normed fit index = 0.99 (chi(2) ((58)) = 68.84, P = 0.16). Significant correlations were found for pain intensity, disability, anxiety, and depression (r = 0.223-0.597, P < 0.01). The general health, social function, role emotional, and mental health domains of the SF-36 consistently demonstrated negative association with catastrophizing across all HK-PCS scores (r =-0.279 to -0.396, P < 0.01). No gender difference was noted for HK-PCS scores (P > 0.05), which is contrary to the existing literature.
Conclusion: This study has illustrated satisfactory psychometric properties of the HK-PCS. We provide evidence for the validity and reliability of the HK-PCS as an instrument for measuring pain catastrophizing in the Chinese patient with chronic pain.