The last questions point to difficulties in determining the age at which a children can consent for themselves and the subtleties of representative consent, in this case consent for the child by someone other than a biological parent. In this case, the ethical issues are made even more complex and difficult because of the involvement of a child. Moreover, in most research involving children, the child is represented by a parent, but in this case there is further complexity because the child is represented by a guardian, a foster parent. Let me first consider the issues that would be raised even if no children or representatives were involved. When, if ever, placebo studies are justified is one such issue.
Drug tests are morally problematic because they put participants at risk.
Since the effects of the drug are not known, there is risk of adverse effects. Indeed, independent of the use of placebos, all researchers have to ask whether the knowledge they will gain is worth the risk to which they expose their research subjects. In this context, research involving placebos might be seen as morally preferable to other research because half the subjects will not, in fact, be put at risk. The problem is that in most placebo studies, the drug or therapy being tested is thought to have a positive effect, and yet those receiving the placebo have no chance of receiving this benefit. They are, in effect, being used to prove a point.