The purpose of this study was to perform a cross-cultural adaptation of the Turkish version of the Centrality of Pain Scale (COPS) and to evaluate its psychometric properties in patients with fibromyalgia syndrome (FMS).
Centrality of Pain Scale was translated and culturally adapted according to guidelines. Clinical and demographic data of the patients were recorded. In addition to the Turkish version of the COPS (COPS-TR), fibromyalgia impact questionnaire (FIQ), Pain Catastrophizing Scale (PCS), Brief Pain Inventory-Short Form (BPI-SF), Beck Depression Inventory (BDI), Generalized Anxiety Disorder 7-item (GAD-7) scale and Short Form-36 were applied. Internal consistency and test-retest methods were used for reliability analysis. Convergent validity was assessed by analyzing the correlations between COP-TR and functional parameters. Divergent validity and responsiveness were also evaluated.
One hundred and four patients (90 female and 14 male) were included. The mean age was 44 years. Good internal consistency (α = .84) and high test-retest reliability (intraclass correlation coefficient = 0.95) were determined. Highest correlations were detected between COPS-TR and BPI-SF pain interference score (r = .64), COPS-TR and PCS (r = .61). There was no significant correlation with non-functional parameters (body mass index, disease duration). It showed high responsiveness (effect size and standardized response mean were 1.66 and 1.94, respectively). The patients filled out COPS-TR in 2 minutes.
COPS-TR is a reliable and valid instrument that shows good psychometric properties. It can be used in clinical practice and scientific research.