Then how do you explain the metastudy that I linked to below
I read the fine abstract of the article you kindly posted in your comment, where it says, "Moreover, the observed association between good adherence to placebo and mortality supports the existence of the 'healthy adherer' effect, whereby adherence to drug therapy may be a surrogate marker for overall healthy behaviour."
This finding (for which I would expect a lot more replication across independent data sets before relying on it too much for my own health) says that patients who make efforts to take care of themselves generally fare better than patients who are so careless that they don't even take physician-prescribed medicines according to the prescription schedule. If, once that difference in patient behavior is taken into account, some patients gain little additional benefit from a particular prescribed drug over the bare lifestyle difference benefit shown by patients taking only placebos, that suggests that the prescribed drugs can be improved (or that physician practice in choosing and dosing the prescribed drugs can be improved) but it doesn't suggest at all that placebos themselves are doing anything beneficial for patients.
"it doesn't suggest at all that placebos themselves are doing anything beneficial for patients."
Fair enough. But those patients who don't take their medicine as prescribed are ~25% of all U.S. patients. So in fact adherence studies are a much better measure of the efficacy of medicine than clinical trials, which means that just because a drug has been shown to have clinical efficacy doesn't mean that it actually at all effective in the real world.
I read the fine abstract of the article you kindly posted in your comment, where it says, "Moreover, the observed association between good adherence to placebo and mortality supports the existence of the 'healthy adherer' effect, whereby adherence to drug therapy may be a surrogate marker for overall healthy behaviour."
This finding (for which I would expect a lot more replication across independent data sets before relying on it too much for my own health) says that patients who make efforts to take care of themselves generally fare better than patients who are so careless that they don't even take physician-prescribed medicines according to the prescription schedule. If, once that difference in patient behavior is taken into account, some patients gain little additional benefit from a particular prescribed drug over the bare lifestyle difference benefit shown by patients taking only placebos, that suggests that the prescribed drugs can be improved (or that physician practice in choosing and dosing the prescribed drugs can be improved) but it doesn't suggest at all that placebos themselves are doing anything beneficial for patients.