Development of a questionnaire to investigate patient compliance with antirheumatic drug therapy

Objective. to develop a rheumatology oriented questionnaire that measures c ompliance to drug regimen and identifies factors that contribute to subopti mal compliance in patients with rheumatoid arthritis (RA), polymyalgia rheu matica (PMR), and gout. Methods. Thirty-two patients (16 RA, 8 PMR, 8 gout) participated in semista ndardized home interviews about their attitude toward their antirheumatic m edication, actual drug intake, and reasons for not taking medication. A foc us group interview with 7 patients (3 RA, 2 PMR, 2 gout) was held. Followin g an advertisement in the rheumatology patient organization magazine (> 800 0 patients) 14 patients (9 RA, 5 PMR) telephoned and explained their reason s for noncompliance. All interviews were recorded on tape, transcribed, and independently reviewed by 2 investigators. Thirty-one statements were sele cted. After a field test, the phrasing of some items was revised. The quest ionnaire was then sent by mail to 117 consecutive outpatients (58 RA, 30 PM R, 29 gout). Results. Twelve items were excluded because of low or high corrected item-t otal correlation or skew distribution of the answers, internal consistency of the remaining 19 items was intermediate (0.71). Discriminant analyses wi th an overall patient self-report compliance measure showed a sensitivity o f 98%, a specificity of 67%, and a Cohen's kappa of 0.71. Stepwise discrimi nant analyses revealed that 3 items classified 84% of all cases correctly w ith a sensitivity of 99%, specificity 80%, and kappa 0.78. Conclusion. The 19 item measure was well accepted. It is useful to detect p ossible barriers for optimal compliance and to predict patient compliance t o drug regimen.