Adaptation and validation of the rheumatoid arthritis quality of life scale for use in Canada

Objective. The Rheumatoid Arthritis Quality of Life questionnaire (RAQoL) w as developed simultaneously in the UK and the Netherlands to measure qualit y of life in patients with RA. We adapted and validated the RAQoL for the E nglish-Canadian and French-Canadian languages and culture. Methods, The UK RAQoL was translated into French-Canadian by a bilingual tr anslation panel, Separate lay panels were then used to ensure that this and the English-Canadian instruments were appropriate for use with Canadian pa tients. Interviews were conducted with 15 French-Canadian and 15 English-Ca nadian patients with RA to determine the content validity. Reliability and construct validity were established by means of test-retest mail surveys co nducted with 92 French-Canadian and 87 English-Canadian RA patients. The su rvey consisted of the adapted RAQoL, the Health Assessment Questionnaire (H AQ), and a demographic questionnaire, Results. The RAQoL was successfully adapted for both the French and English -Canadian cultures. Field testing showed both Versions to be well received by respondents. Of the French-Canadian patients included in the postal surv ey, 52 responded at Time 1 and 50 at Time 2, For the English-Canadian sampl e, 54 responded at both time points. Missing data rates for the RAQoL were low and floor and ceiling effects were minimal, Test-retest reliability was good for both versions: 0.87 for the French-Canadian and 0.95 for the Engl ish-Canadian, Alpha coefficients (0.92 for the French-Canadian. 0.93 for th e English-Canadian) showed the items to be adequately interrelated and scor es on the measure showed moderate to high correlations with the HAQ, confir ming construct validity. Both versions of the RAQoL were also able to disti nguish patient groups that differed according to perceived health status an d perceived severity of RA, In addition, the French-Canadian version was ab le to distinguish patients who rated today as bad or very bad from those wh o rated today as good or very good. Conclusion. The new versions of the RAQoL were well received by both French and English speaking Canadians. The psychometric quality of the adapted qu estionnaires means they are suitable for inclusion in clinical trials invol ving patients with RA.