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Streamlined mail-based methods for large randomised trials: lessons learnt from the ASCEND study
Marion M Mafham1, Louise J Bowman2,3, Richard J Haynes2,3
1Clinical Trial Service Unit and Epidemiological Studies Unit, Nuffield Department of Population Health, University of Oxford, Richard Doll Building, Old Road Campus, Roosevelt Drive, Oxford, OX3 7LF, UK. marion.mafham@ndph.ox.ac.uk.
Streamlined clinical trials, like ASCEND, simplify design and conduct for cost-effectiveness. Mail-based recruitment and follow-up in large randomized trials improve efficiency and participant adherence.
Area of Science:
- Clinical Trials Methodology
- Cardiovascular Disease Prevention
- Diabetes Management
Background:
- Large randomized trials are essential for reliable intervention assessment but face increasing complexity and cost.
- Streamlined trial designs are needed to simplify conduct while retaining essential elements for research questions and participant safety.
Purpose of the Study:
- To review the streamlined design of the 'A Study of Cardiovascular Events iN Diabetes' (ASCEND) trial.
- To discuss the success and limitations of mail-based recruitment and follow-up in large clinical trials.
Main Methods:
- The ASCEND trial employed a two-by-two factorial design assessing low-dose aspirin and n-3 fatty acid supplementation.
- Key streamlined features included mail-based recruitment and follow-up, eliminating in-person visits, and utilizing a run-in period.
Main Results:
- ASCEND successfully randomized 15,480 participants with diabetes but no overt cardiovascular disease.
- The study achieved good adherence and near-complete follow-up, demonstrating cost-effectiveness compared to traditional clinic-based trials.
Conclusions:
- Streamlined, mail-based trial designs are effective for large-scale randomized studies, offering significant cost savings.
- Such methodologies are crucial for addressing important clinical questions and improving public health outcomes.
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