Modelling non-demanders in choice experiments.

Discrete choice experiments have the advantage that they can study preferences in health care where revealed preference data is not readily available. However, as a substitute for actual observed market led data, the experimental set-up for hypothetical situations must mimic the circumstances under which actual choices are made. One situation that a consumer/patient might face is an opt-out option. They might not choose to accept any of the positive actions available and as such will be a non-demander of the health care on offer. This paper explores issues raised in the modelling of such data within an experiment looking at women's preferences for cervical screening services. Copyright 2003 John Wiley & Sons, Ltd.