Exploring the relation between impairment rating by DAS-28 and body function, activity participation, and environmental factors based on ICF hand core set in the patient with rheumatoid arthritis.

Hand problems associated with rheumatoid arthritis lead to subjective impairment, activity limitation, and restrictions on participation. This relation is very complex. Assessment of individuals' activities is important to determine how hand problems affect not only body functions but also daily life activities. The aim of this study was to link and allocate items of disability questionnaires with ICF components based on ICF hand core set. The other objective was to examine the relationship between impairment and ICF components determined on the basis of disability questionnaires in participants with rheumatoid arthritis. Impairment was evaluated by use of Disease Activity Score-28. Disability questionnaires were Disabilities of Arm, Shoulder and Hand Questionnaire, Michigan Hand Outcomes Questionnaire, Duruoz Hand Index, and Arthritis Impact Measurement Scales 2 (n = 100). Items of disability questionnaires were linked with ICF hand core set as a result of three expert opinions. Michigan Hand Outcomes Questionnaire covered the highest number of body function categories and Arthritis Impact Measurement Scales 2 covered the highest number of ICF hand core set. For all questionnaires, while impairment (Disease Activity Score-28) had moderate correlation with subjective impairment (body function scores) and activity/participation; subjective impairment had high and moderate correlation with activity participation. Arthritis Impact Measurement Scale 2 is the most appropriate to perform a more comprehensive biopsychosocial assessment. Clinician's assessments and impairment levels reported by patients with rheumatoid arthritis are interrelated. Impairment levels reported by patients with rheumatoid arthritis are also affected by environmental factors.