A large study of the effects of oxygen levels on extremely premature babies failed to inform the infants’ parents that the risks of participating could involve increased chances of blindness or death.  http://www.nytimes.com/2013/04/11/health/parents-of-preemies-werent-told-of-risks-in-study.html?hp  Babies assigned to a high-oxygen group were more likely to go blind and babies assigned to a low-oxygen group were more likely to die than if they had not participated. Ultimately, 130 babies out of 654 in the low-oxygen group died, and 91 babies out of 509 in the high-oxygen group developed blindness.  “the researchers had sufficient available information to know, before conducting the study, that participation might lead to differences in whether an infant survived, or developed blindness, in comparison to what might have happened to a child had that child not been enrolled in the study.”

The risk the consent form did mention was far less significant: abrasion of the infants’ skin by an oxygen monitoring device. It also said there was a possible benefit to participating — a decreased need for eye surgery depending on the group the infant was assigned to.

In the 1930s, when scientists conducted research on impoverished black men in Alabama in the Tuskegee syphilis experiment without explaining the objective of the study to the men or helping them get treatment once it became widely available. The experiment led to a public outcry and numerous patient protections, like the requirement of “informed consent.”