Suppose you are working in an alcoholism treatment unit, and a proposal is made to initiate a new treatment program that looks promising but is largely untested. Under what conditions do you think it would be acceptable to use a control group as a comparison group that does not receive any treatment? Under what conditions would it be ethically unacceptable? How might you avoid some of the ethical dilemmas that come from withholding treatment but still use some form of control group for comparison?