Introduction/objectivesDespite its importance, adherence to treatment has not been sufficiently studied in Behcet's disease (BD). The aim of this study was to evaluate medication adherence in BD using the Compliance Questionnaire of Rheumatology (CQR) and factors potentially affecting it.MethodThis cross-sectional study included 67 consecutive BD patients including 57 (85%) males with a mean age of 35.19.27years and mean disease duration of 12991months. The cumulative clinical manifestations, the Behcet's Disease Current Activity Form (BDCAF) score, and the Vasculitis Damage Index (VDI) were recorded. The CQR, Socioeconomic Status Questionnaire for Health Research in Egypt (SES), the Beliefs about Medication Questionnaire (BMQ), and the Short Form 36 (SF-36) quality of life assessment questionnaire were administered to the patients. Linear regression analysis was done to determine independent predictors of CQR.Results p id=Par3 The mean BDCAF score was 3.27 +/- 3.54 and the VDI was 3.36 +/- 2.21. The mean CQR score was 69.2 +/- 11.79. The CQR score varied significantly among different health sources (p=0.02), with no relationship detected with other sociodemographic characteristics, nor with clinical characteristics or the SF-36. Among the investigated medications' complexities, severity of side effects showed significantly different CQR scores (p=0.004), and a weak positive correlation between medications' numbers and the CQR was detected. Predictors for higher CQR scores included the necessity beliefs score of the BMQ (=1.1, p<0.001); whereas, predictors for lower CQR scores were the harm and concern BMQ subscales ((=-1.5, p=0.004) and (=-0.72, p=0.032), respectively).Conclusions p id=Par4 Beliefs about medications were the only predictor for adherence in our cohort.