There is something of a sea change going on right now (perhaps it's still too early to use that term, but the tide is surely shifting). Let's distinguish two t

There is something of a sea change going on right now (perhaps it's still too early to use that term, but the tide is surely shifting). Let's distinguish two types of "negative" studies: one is a study whose result simply failed to be positive. "We performed exome sequencing in a kindred but failed to identify a common mutation in all affected members of the family." There are so many possible error modes, including erroneous fundamental assumptions about where this family's defect lies, that this is possibly uninteresting to virtually anyone. The second type is a study that was done in a way that was powered to detect a positive result, had it been there. "We performed a randomized controlled trial in 1,000 patients with hemochromatosis to determine whether iron chelation was non-inferior to bloodletting for the treatment of hemochromatosis. We found that iron chelation failed to achieve non-inferiority." In this example (which is made up), this is a negative result that teaches us something immediately, and which could change practice (or could tell everyone that practice is not about to change despite rumors of a potentially new therapy). Along these lines, to prevent these valuable yet "negative" trials from going unpublished, high-end medical journals such as the New England Journal of Medicine are now requiring that all trials enter into a registry.