Patients' preferences for enrolment into critical-care trials.

Abstract

Most critically ill patients are incapable of providing informed consent for research. We sought to determine patients' preferences for different consent frameworks for enrolling incapable patients into critical-care trials. Prospective observational and structured interview study. Five university-affiliated hospitals in Ontario. Two-hundred and forty consecutive capable and consenting survivors of critical illness. Participants considered four frameworks for enrolling incapable patients into clinical trials using a baseline scenario and three permutations for: risk (very low vs. high), treatment type (new vs. currently available), and availability of substitute decision-maker (yes vs. no). For each scenario, patients chose their preferred framework and rated the acceptability of each framework using a seven-point Likert scale. Most (180/240; 76%) patients selected "consent by substitute prior to enrolment" as their preferred framework; this also received the highest baseline acceptability ratings ("acceptable" or "highly acceptable" 207/240; 87%). Modifying risk or treatment type did not substantially change these ratings. A minority of patients rated delayed consent as unacceptable or highly unacceptable in both the baseline scenario (48/240, 20% delayed to substitute; 57/240, 24% delayed to patient) and when a substitute was unavailable (34/240; 15%). Most survivors of critical illness found the usual practice of obtaining informed consent from a substitute decision-maker prior to enrolment in a clinical trial to be acceptable. Nearly half of patients considered foregoing informed consent to be unacceptable, whereas a minority considered enrolment followed by delayed consent to be unacceptable even when a substitute was unavailable. These approaches should, therefore, only be considered when deviating from the usual practice of obtaining consent from a substitute decision-maker is truly justified, such as where treatments being tested need to be delivered as soon as possible in order to be effective.