Related Experiment Video
Updated: May 4, 2026
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Frequency and Distribution of Crossovers in Caenorhabditis elegans Meiosis by SNP Genotyping using Real-time PCR
Published on: July 11, 2025
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The misguided ethics of crossover trials
Vinay Prasad1, Christine Grady2
1Medical Oncology Branch, National Cancer Institute, National Institutes of Health, 10 Center Dr. 10/12N226, Bethesda, MD 20892, United States.
Contemporary Clinical Trials
|December 25, 2013
Summary
Crossover designs in cancer clinical trials, while popular for recruitment and patient benefit, may actually hinder meaningful research. This approach can compromise a trial
Area of Science:
- Oncology
- Clinical Trial Design
- Medical Ethics
Background:
- Crossover designs are increasingly utilized in cancer clinical trials, including those assessing novel drug efficacy.
- Motivations for crossover include enhancing trial recruitment and offering investigational agents to more patients.
Purpose of the Study:
- To critically evaluate the ethical implications of employing crossover designs in oncology clinical trials.
- To argue that the ethical inclination towards crossover may be misguided and potentially unethical.
Main Methods:
- Conceptual analysis and ethical argumentation regarding clinical trial design.
- Examination of the impact of crossover on the ability of trials to answer key clinical questions.
Main Results:
- The pursuit of participant desires through crossover may undermine a trial's capacity to yield meaningful clinical insights.
- Trials that cannot answer a significant clinical question are inherently unethical.
Conclusions:
- Employing crossover strategies in oncology clinical trials can compromise scientific integrity and ethical standards.
- The ethical justification for widespread crossover use in cancer research requires re-evaluation.
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