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Participant informed consent in cluster randomized trials: review.
Bruno Giraudeau1, Agnès Caille, Amélie Le Gouge
1INSERM, U738, Paris, France. giraudeau@med.univ-tours.fr
Plos One
|July 14, 2012
Summary
In cluster randomized trials (CRTs), participant consent and reporting are often inadequate. Improved reporting on consent and recruitment is crucial for assessing selection bias in these complex studies.
Area of Science:
- Medical Ethics
- Clinical Trials Methodology
- Public Health Research
Background:
- The Nuremberg Code establishes participant consent as fundamental in medical research.
- Cluster randomized trials (CRTs) present unique challenges for obtaining informed consent due to large group randomization and unavoidable interventions.
- Providing complete participant information in CRTs may introduce selection bias, impacting methodological rigor.
Purpose of the Study:
- To assess the requirement and type of participant informed consent in CRTs.
- To evaluate the risk of selection bias in CRTs due to the nature of participant information and recruitment.
- To examine the reporting standards of ethics committee approval and participant consent in CRTs.
Main Methods:
- Systematic review of CRT reports published in MEDLINE in 2008.
- Survey of corresponding authors to gather details on informed consent and participant inclusion processes.
- Analysis of 173 identified CRT reports, with responses from 113 authors (65.3%).
Main Results:
- 23.7% of CRT reports lacked essential ethics committee approval or participant consent information.
- Participant consent was for data collection only in 53.1% of studies, and group allocation was unspecified for participants in 58.5%.
- Only an estimated 56.6% of CRTs were free from potential selection bias due to incomplete reporting of the recruitment process.
Conclusions:
- Reporting on ethics committee approval and informed consent in CRTs is suboptimal.
- CRTs reports should clearly distinguish consent for intervention administration versus data collection.
- Full description of the participant recruitment process, including awareness of group allocation, is necessary for bias assessment.
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