Box 1. Defining pretesting in choice experiments

One of the key stages of developing a choice experiment, pretesting is a flexible process where representatives of the target population are engaged to improve the readability, presentation, and structure of the survey instrument (including educational material, choice experiment tasks, and all other survey questions). The goal of pretesting a DCE is to improve the validity, reliability, and relevance of the survey, while decreasing sources of bias, burden, and error associated with preference elicitation, data collection, and interpretation of the data.