Review ArticleReporting of consent rates in critical care studies: room for improvement
Introduction
Hundreds of thousands of patients are admitted each year to critical care units worldwide [1]. These patients represent a vulnerable patient population in whom research is necessary to improve care. The performance of research studies involving all human subjects requires the procurement of informed consent from patients or their delegates [2]. This requirement is mandated by the Declaration of Helsinki [2] and is enforced by local Research Ethics Boards (REBs) and related legislation [3], [4]. Most medical journals require authors to include statements on whether REB approval and written informed consent were obtained in their submitted manuscripts but do not require them to report the actual consent rate obtained in their study.
Obtaining informed consent from critically ill patients in intensive care units (ICUs) involves unique challenges specific to the ICU environment including the need for surrogate decision makers [5], time sensitive protocols [6], [7], highly stressed families [5], [8], and high mortality rates [9]. These difficulties result in variable consent rates [10], [11] and potential selection biases of participants enrolled into critical care studies [12], [13], [14]. Variable or unknown consent rates make it difficult for researchers to determine sample sizes, budgets, and timelines for future studies. In addition, selection biases that may occur in studies with low consent rates lead to difficulties with interpretation and extrapolation of study results [12], [13]. Therefore, to correctly interpret the results of a given study, it is important for researchers to explicitly report their obtained consent rates in their published manuscripts. We found two studies examining the reporting of ethics documentation in critical care publications; however, neither study documented the actual consent rates reported in the manuscripts reviewed [15], [16].
Therefore, our objective was to determine the frequency of consent rate reporting in a sample of critical care studies published in 2013 in eight specific medical journals.
Section snippets
Methods
We extracted data from all critical care studies published in 2013 from eight high impact medical journals to determine what percentage of studies reported their actual consent rates.
Results
A total of 1,871 articles were screened from the eight selected journals (see Fig. 1). A total of 1,652 articles did not meet inclusion criteria resulting in 219 being eligible for extraction. Of those, 63 studies had consent waived by their REB and were therefore excluded. Data were extracted from a total of 156 articles.
Discussion
This is the first study to assess reported consent rates in critical care research. We found that although 96.8% of articles explicitly stated that they had obtained REB approval and 90.4% reported the specific model of consent used only 30.8% of the critical care studies reviewed reported the actual consent rate obtained. The transparent reporting of consent rates in published articles is important to determine potential sources of bias and the validity and generalizability of the results. In
Conclusion
Actual consent rates are reported in less than one-third of recent critical care studies which may have implications for the generalizability of their results and planning of future studies. We would strongly encourage journals to require reporting of obtained consent rates and would encourage investigators to ask their REBs for permission to collect a minimum, deidentified data set on patients who are eligible for research studies but elect not to participate. These two measures would improve
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Cited by (14)
Including migrant oncology patients in research: A multisite pilot randomised controlled trial testing consultation audio-recordings and question prompt lists
2022, Contemporary Clinical Trials CommunicationsCitation Excerpt :For Arabic, Cantonese, and Greek-speaking patients, consent rates ranged from 25 to 47%. These consent rates are much lower than the reported average in systematic reviews of clinical trial consent rates (>82%), although the numbers in this study are too low to make firm conclusions, they indicate a trend that migrant and refugee patients may be more hesitant about research participation [28,29]. Wariness or unfamiliarity about research and family concerns were common reasons for non-consent.
Consent Rates Reported in Published Pediatric Randomized Controlled Trials
2020, Journal of PediatricsCitation Excerpt :Among all initiated pediatric RCTs, including those that terminated early owing to poor enrollment, consent rates are likely lower. The average consent rate was higher than we anticipated, but is still slightly lower than that of an adult critical care study, which found a median consent rate of 86.9%, confirming prior studies indicating the added challenge of consent in pediatric trials.8 To our knowledge, there are no other publications that explore the average reported consent rate in pediatric RCTs.
A systematic review of discontinued trials suggested that most reasons for recruitment failure were preventable
2016, Journal of Clinical EpidemiologyCitation Excerpt :Another frequent category was poor motivation of eligible participants. Investigators rarely mentioned their estimated proportion of consenting participants out of eligible patients, which had been criticized before in a review on critical care research [25]. In our sample, only 1% of RCT reports mentioned a pilot or feasibility phase which would be the ultimate test of both the number of eligible and the number of consenting patients.
Trend in Clinical Trial Participation during COVID-19: A Secondary Analysis of the I-SPY COVID Clinical Trial
2023, Critical Care Explorations
This work was performed at the Children's Hospital of Eastern Ontario.
Funding: None.
Conflict of interest: None.
- 1
Present address: Queens University, 99 University Avenue, Kingston, ON K7L 3N6, Canada.