Time to collect informed consent to participate to randomized control trials in Intensive Care Unit patients: a...

This retrospective study analyzed the time interval to obtain patient consent for participation in 14 randomized clinical trials (RCTs)(505 patients) across three French Intensive Care Units.

The following time intervals (median values and interquartile ranges [IQR]) were measured: from patient consent to inclusion; from relative consent to inclusion; from inclusion to patient consent (initial relative consent); from emergency procedure inclusion to direct final patient consent; from emergency procedure to relative consent; and from relative consent to final patient consent. The distribution of the time to first consent was modelled using maximum likelihood parameter estimation of a zero-inflated log-normal distribution accounting for right-censoring.

Pre-inclusion consents were obtained from 106 (21.0%) patients and from 36 (7.1%) patient relatives (with deferred patient consent in 21 patients (4.2%) (median time = 12 [5-29] days), and no deferred consent in 15 patients [3.0%]). Emergency procedure was necessary in 363 patients (71.9%): 147 patients (29.1%) gave deferred consent directly (median time = 4 [2-9] days). In 156 patients (30.9%), relatives gave initial consent (median time: 3 [1-7] days), with subsequent 60 patient consents (11.9%) (median time = 19 [7-51] days). No further patient consent was obtained in 96 cases (19%). Additionally, in 60 patients (11.9%), neither patient nor relative consent could be secured.

Emergency procedure was the predominant method of patient enrolment (71.9%) in RCTs. The median time to obtain patient consent ranged from 0 to 19 days. A final consent could not be obtained in 33.9% patients.