Objective: The Health Assessment Questionnaire Disability Index (HAQ-DI) is the most widely used measure of function in rheumatoid arthritis (RA). To enhance the incorporation of patients’ view in outcome assessment, this study aimed to evaluate individualized forms of the HAQ-DI.
Patients and methods: HAQ-DI data were prospectively obtained from 370 RA outpatients treated with leflunomide over a 6-month period. At baseline and final visits, patients had to rate the importance they attached to each activity addressed by the 20 HAQ-DI items, and to select the 5 activities they considered the most important. Different individualized scales were evaluated: scales preserving all domains, in which the score for each item is multiplied by or added to its importance; and scales involving for each patient only the 5 most important items. The psychometric properties of theses scales were compared to those of the HAQ-DI.
Results: For each HAQ-DI item, severity and importance scores were weakly correlated. Scores for all individualized scales were highly correlated with the HAQ-DI score (rho>0.75). All scales had a good internal consistency (Cronbach’s alpha: 0.87 to 0.88). Compared to the HAQ-DI, individualized scales did not have better sensitivity to change (standardized response mean: 0.64 to 0.69 vs. 0.74).
Conclusion Individualized scales have similar properties as the HAQ-DI. However, individualized questionnaires measuring importance gave complementary information to the measure of disability. Therefore, even if individualization is probably not needed for group assessment in all randomized controlled trials, the use of individualized questionnaires could be clinically relevant for individual RA patients.
Statistics from Altmetric.com
Web Only Data 69/1/97