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the elapsed time before a trial is commenced when no treatment is given to participants in the study.
Farlex Partner Medical Dictionary © Farlex 2012
run-in periodThe period before a clinical trial is begun when no treatment is given. The run-in period can be called a washout period if treatments that participants were using before entering the trial are discontinued.
Segen's Medical Dictionary. © 2012 Farlex, Inc. All rights reserved.