Run-in period is a period between the recruitment and randomization phases of a clinical trial,^[1][2] when all participants receive the same treatment, which may be active treatment, a placebo or no treatment at all. The clinical data from this stage of a trial are only occasionally of value but can serve a valuable role in screening out ineligible or non-compliant participants, in ensuring that participants are in a stable condition, and in providing baseline observations.^[3] A run-in period is sometimes called a washout period if treatments that participants were using before entering the clinical trial are discontinued.

See also

• Data management
• Randomized controlled trial
• Safety monitoring
• Serious adverse event
• Standard operating procedures
• Standard treatment
• Study population

References