Where do the media get all those clinical research stories from - and why do so many medical breakthroughs occur on a Friday?

The answer lies in the existence of a US-based website and e-mail service for health and science journalists.

Eurekalert acts as a broker between the publishers of scientific research, whose esoteric contributions to the advancement of human understanding would otherwise go unread, and the mainstream news outlets, whose need for miracle cure/health scare stories is outweighed only by a lack of medical knowledge.

Essentially, it is just a repository for press releases. But the depth of content in much of the material posted here is sufficient to sate most thirsts, while the range of sources is a revelation in itself. Did you even know there were journals of experimental medicine or molecular psychiatry?

All this content is freely available to the public as it becomes available, along with an archive stretching back to 1996, links to research institutes and so on. And because Eurekalert is produced and controlled by the American Academy for the Advancement of Science, you know you can rely on it.

Naturally, journalists want access to this rich source of stories ahead of the rest of the world, and researchers desperate for publicity to justify their grants are happy to oblige.

Signing up for embargoed releases is akin to joining a secret society, requiring proof of your credentials, and promises signed in blood never to run a story early or exploit your advance knowledge to make a killing on the stock market. But the journalist's effort is amply rewarded.

So no matter what newspapers you buy today, you will find much the same stories about the same arcane advance in medicine, drawn from the same obscure source. And why Fridays? Because that's when The Lancet and British Medical Journal release their big stories, of course.