Author Affiliations: Cardiovascular Health Research Unit, Departments of Medicine, Epidemiology, and Health Services, University of Washington and Center for Health Studies, Group Health, Seattle (Dr Psaty); and Division of Public Health Sciences, Fred Hutchinson Cancer Research Center, Seattle, Washington (Dr Prentice).
In 1992, Hansson et al1 proposed a novel design, the prospective randomized open trial with blinded end-point assessments. The lack of blinding of investigators and patients simplified the conduct of the trial, which would become more similar to routine medical practice than the blinded design. The use of blinding for the adjudication of outcomes would preserve the benefits of a fully blinded trial. A number of trials have used this design to evaluate antihypertensive agents and more recently antidiabetic agents.2- 4 These trials were thought to produce valid and, perhaps, more generalizable results.
Psaty BM, Prentice RL. Minimizing Bias in Randomized TrialsThe Importance of Blinding. JAMA. 2010;304(7):793-794. doi:10.1001/jama.2010.1161