Science is the search for the best theory as such it's hard to rank something as better or worse than we don't know. Thus the default theory is "There is no rel

Science is the search for the best theory as such it's hard to rank something as better or worse than we don't know. Thus the default theory is "There is no relationship between X and Y". For the purposes of this discussion, that's a distinction without a difference. (BTW I edited my comment before your reply showed up, and had deleted the bit you quoted.) More significantly, your suggestion of comparing SSRIs to placebos with side effects strikes me as an excellent idea; it is what Kirsch's study would naturally seem to suggest. I wonder if such studies will ever be undertaken. Edit: I did find at least one such study: http://psychrights.org/research/Digest/CriticalThinkRxCites/Moncrief2004.pdf http://psychrights.org/research/Digest/CriticalThinkRxCites/... Authors' conclusions: The more conservative estimates from the present analysis found that differences between antidepressants and active placebos were small. This suggests that unblinding effects may inflate the efficacy of antidepressants in trials using inert placebos. Further research into unblinding is warranted.