A group of top medical journals is considering asking pharmaceutical companies to disclose clinical trials before they start. I’m no pharma-basher, but this is a terrific idea.

From Statistics 101 we know that if a product is as effective as a placebo, 1 in 20 trials will produce a statistically significant finding due to random chance. Since companies run dozens of trials on each major compound, it is not too hard to produce at least one positive, statistically significant finding suitable for publication. The rest are buried in the “circular file.” This is great marketing but it is not science.

In addition, pre-disclosure of trial design will make it almost impossible to engage in ex post gerrymandering of the results (e.g., by publishing results of a six-month endpoint in a 12-month trial).

Note that the proposed disclosure requirement is not a government mandate. No pharma company would be required to participate. But those who want to publish findings in the most influential medical journals would have a strong incentive to do so.

It remains to be seen whether the medical journals, as dependent as they are on pharma advertising, will follow through on this idea.

Update: Ack! Less than one week blogging, and I’ve already made an error. One of my favorite medical bloggers, Derek Lowe, says pharma companies don’t run dozens of trials on every major compound. He knows this stuff inside and out, so I’ll take his word for it. In my defense, I can only say this: I do know of one company that has run more than a dozen trials for one of its products, and I strongly suspect this is not an isolated case.