Mark Liberman at Language Log has a suggestion:
OK, after years of complaining about the darkness of science journalism, I’m lighting a candle. I’ve found a cure.
…
So the next time you see an article in the popular press about “the genetic basis of X” or “the gene for Y” (and surely you will!), look for the case-subject and control-subject percentages. If you don’t see them (and probably you won’t!), write to the editor and complain.
As he himself points out,
Not, I’m afraid, a cure for the whole syndrome of credulousness, carelessness and misreading. I can’t even pretend that my remedy will have any effect on the underlying causes, which are ignorance of science and the motive of sensationalism. My medicine will only provide symptomatic relief, and only in a specific class of cases, those where scientists (or their press agents) claim to have found “the genetic basis of X”.
However, if each of us can come up with rules for some specific class of cases, it would still improve science journalism dramatically.