Map of life expectancy at birth from Global Education Project.

Monday, May 13, 2013

The Fog of Science

As you may recall, in our last episode, Abraham Flexner has persuaded the world -- or at least the space between the North Atlantic and the North Pacific -- to put medicine on a scientific basis. But, it turns out that is very easy to say and very hard to do.

Back in 1910, people knew more about human biology than they did in 1850 or 500 BC, to be sure. But the usefulness of that knowledge for making or keeping people healthy -- whatever that means, and remember we still haven't figured that out -- was very limited. To take stock briefly of our relevant knowledge at the time, we knew something about pathogenic microbes and the importance of sterilizing surgical instruments and wounds. We didn't have any antibiotics, however. There were some empirical remedies, such as opioid analgesics, and, well, that's about it. We didn't know anything abut endocrinology, genetics, the immune system, neurology, oncology, you name it. You could be doing laboratory research and dissecting cadavers and peering at cells under a microscope but none of it was doing your patients any good.

It so happens that in 1747, a British ship's surgeon named James Lind decided, more or less at random, to feed various stuff to soldiers suffering from scurvy. Two of them got a quart of cider every day, two others got vinegar, two got "elixir of vitriol," which is sulfuric acid; two got sea water; and two got oranges and lemons. You know what happened. However, Lind did not want to recommend that the Royal Navy give sailors oranges and lemons because they were too expensive. It took 50 years before the navy got around to it.

Anyway, as impressive as that was, it wasn't until 1943, nearly 200 years later, that anybody got around to doing another randomized controlled trial. It was a pretty good one, even by modern standards: double blind, although not truly randomized. It was done in the UK, to test the effectiveness of penicillin for the common cold. And it was negative, i.e. it didn't work. Here's the even worse news: to this day, prescriptions for antibiotics continue to be written for people with common upper respiratory tract viral infections.

From then on we continued to see more and more clinical trials, of varying quality; and we came up with more and more categories of effective treatment for problems other than infections susceptible to antibiotics. However, the intrusion of knowledge and evidence into medical practice was gradual and almost as often counterproductive as it was beneficial. There are many reasons for this which continue to vex all of us who work in medicine and related fields, and which incite volcanoes of debate and recrimination. I'll tackle the issues in upcoming posts.

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