Support persons' preferences for the type of consultation and the format of information provided when making a cancer treatment decision.

159 adult medical oncology patients and 64 of their support persons took part in this study. Participants were presented with a set of hypothetical scenarios and asked to indicate their most and least preferred scenario. 92% of support persons (n = 59) completed the DCE. Most preferred to receive two consultations along with written and online information (n = 30, 51%). This was the only scenario that was chosen by statistically significantly more support persons (p =0.037). The proportions of patients and support persons choosing each scenario did not differ significantly from each other (p >0.05). Our findings suggest that when making cancer treatment decisions, clinicians should consider offering patients and support persons written and online information, combined with two shorter consultations.