It seems like you're losing focus of my point. I am merely trying to demonstrate that it's wrong to consider studies of this sort as solid and conclusive evidence about the overall effects of the social interventions under consideration. I mentioned this scenario only as one plausible way in which one of these studies could be grossly inadequate, not as something I'm trying to prove to be the case.
I suppose I don't find it to be particularly plausible. Moreover, it seemed that you were discounting the study as offering any evidence at all regarding long-term effects; whereas it seems to me that short-term effects offer weak evidence regarding long-term effects. If we know something is short-term beneficial, that isn't strong evidence of it being long-term beneficial — but it isn't evidence of it being long-term harmful either.
It's worth it to keep looking — I certainly agree that it's a failure of many social interventions to look at only short-term...
A piece I saw that Benjamin Todd adapted from THINK's module on charity assessment. Some of you may recall the network's recent launch.
cipergoth said that it should be emphasised that this isn't a trick question where the answer is they all worked or none did.
I thought Round 2 would have no effect and expected Round #5 to have no effect not a negative one, I got 6 out of 8 correct. How well did you do?
I recommend checking out the links and references. Gwern's comment there was also interesting.