Consent models in Canadian critical care randomized controlled trials: a scoping review

Area of Science:

• Medical Ethics
• Clinical Trials
• Intensive Care Medicine

Background:

• Ethical considerations in clinical research are paramount, especially in critical care settings.
• Informed consent procedures in intensive care units (ICUs) and pediatric intensive care units (PICUs) present unique challenges.
• Understanding the evolution and acceptance of various consent models in Canadian ICU/PICU randomized controlled trials (RCTs) is crucial.

Purpose of the Study:

• To describe the consent models employed in Canadian-led adult and pediatric intensive care unit (ICU/PICU) randomized controlled trials (RCTs).
• To determine the consent rates associated with different consent models, including alternate approaches, in these trials.

Main Methods:

• A scoping review methodology was utilized, searching major databases (MEDLINE, Embase, CENTRAL) from 1998 to June 2019.
• Included were Canadian-led RCTs involving ICU/PICU patients or their families, assessed by two independent reviewers.
• Data on consent models, ethics approval, and consent rates were abstracted and consensus was achieved.

Main Results:

• A total of 48 RCTs involving 17,558 patients were identified.
• Prior informed consent was approved in 90% of trials, with alternate models like deferred consent (27%), waived consent (10%), and verbal consent (2%) also used.
• Fifteen RCTs (31%) utilized multiple consent models. The use of alternate consent models doubled between 2010-2019 compared to 2000-2009.

Conclusions:

• Alternate consent models, while used in a minority of Canadian-led ICU/PICU RCTs, have seen increased utilization over the past decade.
• This trend suggests a growing acceptance of alternate consent models by Canadian ethics review boards and the research community for critical care trials.