[HWR_14]

People opt into the study in the first place. I'm willing to bet that no one opts into the study hoping to be in the control group.

[falcor84]

Well, some medical studies pay good money, so it's perfectly rational to sign up for these and hope to get the placebo.

[HWR_14]

Fair enough. I tend to think of most of them as paying just a small amount where the main goal is to get treatment, but I'm sure some pay better than others.