Determination of the Appropriate Quality of Life Scale for Patients with Rheumatoid Arthritis and Osteoarthritis

Abstract

Objectives: A large number of quality-of-life scales are used to assess the effects of various diseases on the quality of life. The most commonly used scale is the SF-36 quality of life scale. However, in recent years various versions and shorter forms of this scale have been developed. Quality of life scales, which can be applied in a shorter period and which can be interpreted more easily and which produce reliable and valid results, are preferred more. The purpose of this study is to determine the scales that measure the quality of life better and practical would be appropriate in Osteoarthritis (OA) and Rheumatoid Arthritis (RA). Materials and Methods: Cronbach's alpha coefficient was used for the internal consistency of the scales, the intra-class correlation coefficient was used for relations between item-total score, and the agreement between SF-36 scale and other short forms, and also the Spearman Rank correlation analysis were used for evaluation of the relationships between the total scores of the scales. The criterion validity of the short forms (SF) of the quality of life scale were investigated by using WHOQOLBref and QuickDASH scales. Results: The internal consistency of the scales were found to be at a quite good level. In OA patients, the highest agreement in Physical Function, Bodily Pain and Vitality sub-dimensions of the SF-6D scale were found. On the other hand, Physical Role, Emotional Role and General Health sub-dimensions in the SF-12 scale have higher agreement. In RA, Bodily Pain and Vitality sub-dimensions of the SF-6D were found to have higher agreement, and the SF-12 scale have higher agreement in the Physical Function, Physical Role, General Health and Emotional Role. Moreover, in both disease groups, the validity of SF-12 and SF-6D scales was similar to each other in many conditions, and better than the SF-8 scale. Conclusion: According to the results, SF-12 or SF-6D scales could be used effectively to evaluate the quality of life in RA and OA patients.