To estimate patient preferences for attributes of hepatitis C virus (HCV) treatment and patients' assessment of the likely effect of treatment attributes on treatment adherence, HCV patients >/=18 years old completed an online survey that included nine 2-alternative choice questions. Each choice question was defined by the probability of sustained viral response (Efficacy), injection frequency (Frequency), duration of flu-like symptoms after every injection (Flu), injection device (Device), average number of days of work missed each week (Lost Work Days), probability of reversible hair thinning while on treatment (Alopecia) and probability of developing clinical depression while on treatment (Depression). We estimated a mean relative importance weight for each attribute. Patients also answered three rating questions to assess the extent to which treatment attributes might affect adherence. Hundred and fifty patients completed the survey. Efficacy was the most important attribute with a mean relative importance weight of 10 [95% CI: 7.9-12.1]. The remaining attributes were ranked in order of importance as follows: Depression (4.4 [95% CI: 3.6-5.1]), Flu Days(FrequencyxFlu) (3.7 [95% CI: 2.2-5.3]), Lost Work Days (2.9 [95% CI: 2.3-3.5]), Alopecia (1.3 [95% CI: 0.7-1.9]) and Device (1.2 [95% CI: 0.4-2.0]). Patients with prior treatment experience were less likely to indicate that treatment attributes would affect adherence. Patients also indicated that increases in the number of flu days would increase the likelihood of nonadherence to treatment. Sustained viral response is the most important treatment attribute to patients but treatment side effects might affect treatment adherence
