werner@aecom.UUCP (Craig Werner) (05/27/85)
> Will Martin asks: > > If you are testing a truly effective medication, say for some serious > disease or condition, and are conducting a blind or double-blind test > where some participants get placebos and some the medication, and a > number of the control group die because they got only placebos, while > all the test subjects survive because this experimental medication was > really effective, have you not violated the Hippocratic oath (and also > laid yourself open for damages, no matter what you had the participants > sign), by denying this (admittedly experimental) medication to people > who could possibly have been saved by it? This is a good point, and the paradox caused by it has in fact really caused the demise of true double-blind studies. It is no longer ethical to test a drug that has a known positive effect against a true placebo, only against another drug and/or therapy. One example will suffice. In the Multi-Risk F(?) Interventional Trial (known affectionately as MR-FIT), a study was done to see if reducing high blood pressure would actually reduce death rate from Stroke and/or Heart Attack. Instead of dividing the group into treatment and no-treatment, the study was divided into those who received intensive, aggressive, regular, and free care, and those who were referred to their normal doctor. This is how the dilemma Will Martin posed was circumvented in this case: Just to go on about MRFIT itself: The data is still coming in, but it is clear that: 1) Both groups experienced a drop in death rate as compared to the US as a whole. 2) The drop was not much greater in the Experimental group than in the Referred Group. (This could just be an indication that people who went to their physicians might have actually received the same treatment) 3) The drop in death rate also occurred in causes of death totally unrelated (at least so far) with high blood pressure. Incidentally, this study has been misused by Phillip-Morris in their Anti-anti-smoking campaigns. They cite MRFIT as 'proof' that smoking isn't really all that bad. (The reason is that the experimental group in MRFIT had to quit smoking if they did, but a look at the data will probably show that a good percentage of the control did also -- and Phillip Morris doesn't mention that fact. -- Craig Werner !philabs!aecom!werner "The world is just a straight man for you sometimes"
seifert@hammer.UUCP (Snoopy) (06/05/85)
In article <1686@aecom.UUCP> werner@aecom.UUCP (Craig Werner) writes: [ referring to a question about withholding treatment during studies ] > This is a good point, and the paradox caused by it has in fact >really caused the demise of true double-blind studies. It is no longer >ethical to test a drug that has a known positive effect against a true >placebo, only against another drug and/or therapy. Why can't double-blind tests be used when comparing one drug against another drug? Double-blind means neither the patient, nor the person adminstering the pill (shot, whatever) knows which group the patient is in. It doesn't matter whether one group is getting a placebo or another drug, the test can still be double-blind. Certain treatments are difficult or impossible to do double-blind. For example, how would you do a double-blind test comparing plaster casts to 'soft' casts? Snoopy tektronix!mako!seifert