Study bystanders and ethical treatment of study participants-A proof of concept.

The ethics of research on human subjects is often construed as a fine balance between the interests of patients in need of novel health interventions, and those of study participants who should remain safe in the process. But there is a third group in the mix. Some people belong to neither category, yet research can affect or jeopardize them. Call such people "bystanders." This article shows that thinking about bystander protection can question whether there is an upper limit on the risks that studies may legitimately visit upon their participants. Thus, thinking about appropriate bystander protection can shed light on the appropriate protection of study participants. Core research ethics, which focuses on the latter, must consider the former as well.