The reliability and validity of the Turkish version of the graded chronic pain scale in patients with chronic low back pain.

Abstract

To translate and cross-culturally adapt the Turkish version of the Graded Chronic Pain Scale-Revised (GCPS-R) and to evaluate its reliability and validity. The prospective and cross-sectional study was performed with 102 low back pain patients (67 women, 35 men). Patients were asked to complete the GCPS-R twice, one week apart. Visual Analog Scale (VAS), Roland Morris Disability Questionnaire (RMDQ), Short Form-36 (SF-36), Fear Avoidance Beliefs Questionnaire (FABQ) were filled only in the first evaluation. Test-retest reliability was analyzed with intraclass correlation coefficient (ICC). Internal consistency was measured using Cronbach's α. The minimal detectable change (MDC₉₅) was calculated based on the standard error of measurement (SEM₉₅). The construct validity was analyzed using the Pearson correlation coefficient. Exploratory factor analysis was calculated to explore the factor structure of GCPS-R. The mean age of the patients was 45.2 ± 13.1 years. The internal consistency was acceptable, and test-retest reliability was excellent (α = 0.933, ICC = 0.972). SEM₉₅ and MDC₉₅ for the total score were 2.07 and 5.73, respectively. VAS measured for both rest and activity were strongly correlated with GCPS-R (r > 0.50). The correlation between the total score of GCPS-R and RMDQ was excellent (r = 0.677, p < 0.001). SF-36's; physical function, role physical, bodily pain and social function subscores were strongly correlated with GCPS-R (r > 0.50). There was moderate correlation between GCPS-R and the physical activity subscore of the FABQ (r = 0.494, p < 0.001). GCPS-R had a single factor structure as expected. The Turkish version of GCPS-R is a valid and reliable questionnaire in patients with chronic low back pain. Level of Evidence II (Diagnostic: individual cross-sectional studies with consistently applied reference standard and blinding).