For a thing that is "nothing," placebo has been much in the news lately. Whenever the media have mentioned placebo this year, it often has been in the context of clinical trials overseas for treatments to prevent perinatal HIV transmission. The studies were controversial because most of them employed placebo controls with the various treatments being tested, although trials in the United States and France already had indicated that the antiretroviral drug zidovudine (AZT) reduced the incidence of mother-to-child transmission of type 1 HIV (E.M. Conner et al., New England Journal of Medicine, 331:1173-80, 1994). A debate erupted over whether it was proper to give people placebo when an effective therapy was available, even though the new studies were attempts to develop treatments that would be affordable in these developing countries, where the full AZT course is too expensive to be widely obtained.
BLIND OR BALANCED? Subjects who were aware ...
