The incorporation of the patients’ perspectives in drug developments and assessments is receiving increasing
recognition. Both regulators and industries understand that patients and care-partners who live with a disease on a
daily basis have developed their own knowledge, views and preferences on the benefits and risks of the medicine they
receive, or they could receive.
Discrete Choice Experiments (DCEs) are recognized gold standard tools to explore patients’ preferences in health care.
They offer a systematic method for eliciting preferences and quantifying both the relative importance of treatment
attributes in the choice of treatments and the tradeoffs patients are willing to make between the benefits and risks of
treatments. They are conducted as surveys with many simple questions (direct pairwise choices) in a large sample of
patients. A statistical model is then fitted to the individual responses, and the parameter estimates could be interpreted
as preference weights, which represent how the treatment characteristics contribute to the choice of one treatment
over another by the patients. Several experimental designs (number of questions asked to each patient, order of these
questions etc.) have been proposed in the literature, with advantages and drawbacks in terms of feasibility, variability
and bias of the parameters. The sample size if often determined empirically from previous studies, and no analytical
formula have been proposed for this purpose yet.