The beauty of a randomized study is that it can equalize the levels of smoking addiction, reasons for wanting to quit, and motivation to quit across groups. In addition, it equalizes other confounders, including unknown confounders which could affect the study results. There is no way for a survey study to accomplish this. Thus, to simply throw out the RCT is quite unscientific, in my opinion. It throws out one of the most valid pieces of evidence that is necessary to make an informed judgment about the effect of these products: the differences in effectiveness of the products under conditions in which confounding cannot throw off the results.

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