Objective: The aim of this study was to measure women's preferences about decision-making and their impact to participate or not to a hypothetical randomised controlled trial (RCT).
Methods: We surveyed prospectively breast cancer patients invited to participate in a clinical RCT (group 1a=201 acceptances, group 1b=66 refusals) or not invited (group 2=188). All women had the same treatment.
Results: Decision-making preferences of patients who had refused clinical RCT entry were more patient's centred (72.3%) compared to those of patients who accepted (35.0%, P<0.001). Altruism was not a significant determinant of patients' participation. Randomisation was considered acceptable in 52.0% (group 1a) compared to 16.9% and 21.1% for group 1b or group 2, respectively (P<0.001). It was the main predictor of willingness to participate in a hypothetical RCT (adjusted odds ratio (OR(adj)) 4.6; 95% confidence interval [2.7-7.7]; P<0.001) with the patient group allocation (OR(adj) group 1a=5.0 [2.9-8.7]; group 1b=0.2 [0.0-0.8]; group 2=1 [referent]; P<0.001). After multivariate adjustment, willingness to participate was also significantly related with medical decision-making preferences (OR(adj) 2.2 [1.0-4.9]; P=0.045), with the feeling of being unable to refuse a doctor's proposal (OR(adj) 1.8 [1.1-3.2]; P=0.031), and with satisfaction with doctors' communication (OR(adj) 3.1 [1.5-7.8]; P<0.001).
Conclusions: Patients' acceptance to participate in a RCT is preferred to be doctor's decision, whereas refusal is a personal one. When proposing a RCT, doctors must deal with patients' a priori negative feelings about randomisation. They should thoroughly discuss the reasons for and importance of randomisation as well as the other aspects of participating in the trial in order to give patients all of the information they need to make an informed decision.