Assessing treatment tolerability for rheumatoid arthritis. Validation and practical applications of the 'TOL-AR-18 questionnaire'

Introduction: Given the lack of standardized tools to assess tolerability from patient's perspective, we carried out the validation of a questionnaire to asses treatment tolerability for rheumatoid arthritis (RA): TOL-AR-18.

Methods: The TOL-AR-18 was validated in the cross-sectional observational study in adult patients with RA. Socio-demographic and clinical variables were collected. Patients completed the TOL-AR-18 and ARTS questionnaires and a question about their general health status.

Results: Data of 66 patients with a mean age (standard deviation; SD) of 56.71 (10.50) years were analyzed; 66.7% were women. Mean (SD) time to disease progression was 10.76 (8.23) years, and time from first treatment initiation was 9.24 (7.70) years. Patients did not report other adverse events rather than those included in the TOL-AR-18. The questionnaire was feasible with high internal consistency (Cronbach's α >0.90). Discriminant validity was moderate, with significant differences between patients in remission and all other, and between patients who did not report adverse events and the rest (P<.05). Convergent validity was moderate-low when correlated with the ARTS questionnaire.

Conclusion: The TOL-AR-18 is valid for use in a clinical setting and useful as an additional tool for all professionals to manage and assess tolerability in RA.