An evaluation of patients' willingness to trade symptom-free days for asthma-related treatment risks: a discrete choice experiment.

Background. Not taking treatment preferences into account may lead to patients' inappropriate use of asthma treatments. The objective of this study was to quantify these preferences, in terms of risk-benefits trade-offs, for six asthma treatment attributes using a discrete choice experiment (DCE). Methods. Adult asthma patients (n = 157) participated in the study. The custom-designed DCE measured preferences for treatment effectiveness (symptom-free days), potential risk (oral thrush and tremor/heart palpitation), ease of use (frequency of daily administration and number of inhalers required), and cost. A nested logit model was used to determine the relative preferences of each attribute, from which the marginal rates of substitution were calculated. Segmented models were used to test for interactions between cost and treatment benefit with socioeconomic status and medication use. Results. Relationships between preferences and all attributes were in the hypothesized direction. On average, patients were wi...