Clinimetric properties of WOMAC index in Greek knee osteoarthritis patients: comparisons with both self-reported and physical performance measures

Abstract

This observational study aimed to examine the clinimetric properties of the Greek for Greece translation of the Western Ontario and McMaster Osteoarthritis Index (WOMAC(®)). One hundred and twenty-three patients with knee osteoarthritis (mean age 69.5 years) participated in the study. An extensive reliability study was carried out to assess WOMAC's internal consistency and repeatability (8-day interval). In addition, we examined the construct (convergent, nomological and known-groups) and criterion-related (concurrent and predictive) validity of the index against both self-report [SF-36 and combined visual analog/faces pain scale-revised (VAS/FPS-R)] and physical performance measures [timed up and go test (TUG)]. The internal consistency of the WOMAC subscales ranged from high (0.804) to excellent (0.956). Intra-class correlation coefficients for test-retest reliability were excellent, ranging from 0.91 to 0.95. Partial correlation analysis, adjusted for age and use of an assistive device, showed that WOMAC scores were significantly associated with all validation criteria, presenting fair to strong (-0.33 to -0.86) correlation coefficients. WOMAC-function was strongly associated with SF36-function (-0.86) and TUG (0.71), WOMAC-pain to VAS/FPS-R (0.71) and SF36-pain (-0.67). Of all WOMAC outcomes, stiffness subscale had the lowest, though still significant, correlations with all validation criteria. Multiple linear regression analyses indicated that WOMAC-function was a significant factor for TUG, WOMAC-pain for VAS/FPS-R and both for SF36-function and SF36-pain. The WOMAC LK3.1 Greek for Greece Index is a reliable and valid assessment tool for the evaluation of individuals with knee osteoarthritis, showing excellent reliability and significant validity properties.

Diz osteoartriti bulunan hastalarda sinoviyal sıvılarındaki prostanoid düzeyleri ve ultrasonografik bulgular arasındaki ilişki

“…Our results demonstrated that WOMAC scores were positively correlated with evening VAS and activity VAS. Similar results have been found by Papathanasiou et al 51 . This is the first study for the determination of the association of synovial prostanoid levels with local fat thickness and clinical status in knee OA patients.…”

Validation study of the Forgotten Joint Score-12 as a universal patient-reported outcome measure

“…Correlations between the FJS-12 and the total and subscale scores of the other questionnaires were analyzed using Pearson's product-moment correlation coefficient. In all validity analyses, the coefficient values were characterized as follows: 0.00-0.19 = poor, if any; 0.20-0.39 = fair; 0.40-0.59 = moderate; 0.60-0.79 = good; and 0.80-1.00 = high/strong [15,16]. The ceiling and floor effects of a scale are described as the percentages of patients, showing the best or worst possible score on the scale, respectively.…”

Modified Harris Hip Score as patient-reported outcome measure in osteoarthritic patients: psychometric properties of the Greek version

“…The Greek versions of the PROs Lower Extremity Functional Scale (LEFS-Greek), 27–29 Western Ontario and McMaster Osteoarthritis Index (WOMAC-Gr), 30,31 and the PPMs Timed Up & Go (TUG) test 32,33 and 9-stairs-ascend/desscend (9S-A/D) test 34 were also used in the present study (see Supplemental Material, Appendix).…”