Thursday, Aug 30, 2012

1. EPIDEMIOLOGY: WORDS MEAN WHAT THE DICTIONARY SAYS THEY MEAN.

Is epidemiology a science? Last week's WN said it's not but a lot of people disagreed. I got far more mail than I could answer. This is my response. Im a physicist by training, and a troublemaker by inclination; a lexicographer I am not. So I consulted a number of dictionaries; not one classified epidemiology as a science. However, they characterized it as a "branch of medicine." Does that make epidemiology a science? I don't think so, but I doubt if I will ever again say it's not. The distinction I wanted to make is that science is concerned with the cause-and-effect relationship between physical events. Epidemiology, by contrast, looks for correlation. That's important too. It guides scientists in the search for causality, but to confuse causality with correlation is a serious error in logic. It's also a very common mistake.

2. ZAPPED: WHAT IS THE ORIGIN OF THIS COSTLY MISTAKE?

For nearly two decades staff writer Paul Brodeur performed a genuine public service by informing New Yorker readers of the health hazards of exposure to everything from asbestos, to microwave radiation. Brodeur, however, has no science background and no sense of what the numbers mean; radiation was radiation, whether it was power-line fields or microwaves. In 1979, when epidemiologist Nancy Wertheimer charged that 60 Hz power-line radiation is responsible for childhood leukemia, Brodeur wrote a series of supportive articles in the New Yorker about the dangers of power-line fields. They were gathered together in books with lurid titles like Currents of Death. Brodeur was not there in 1996 when the National Academy of Sciences released the results of an exhaustive three-year review of the possible health effects of exposure to residential electromagnetic fields. He had been fired by the New Yorker four years earlier. The unanimous conclusion of the NAS panel was that "the current body of evidence does not show that exposure to these fields presents a human health hazard." Why had it taken so long, and why had there been no comment from epidemiologists? Perhaps the scientific community should use more direct language in stating conclusions that are so obviously wrong and so dangerous.

3. SCIENCE: WHAT DO WE NEED TO DO DIFFERENTLY?

We need to explain the basics of the electromagnetic spectrum to every literate person. It shouldn't be that difficult. Children are transfixed by the sight of a prism breaking sunlight into a rainbow. They need to understand that the visible rainbow is only a tiny sliver out of a spectrum of electromagnetic radiation that ranges from harmless radio waves to deadly gamma rays. The same spectrum should hang on the walls of every classroom and appear in every news article that talks about cell-phone radiation,skin cancer, and x-rays.

4. POLITICS: WE'LL BE BACK TO CURRENT EVENTS IN THE NEXT ISSUE.



Bob Park can be reached via email at whatsnew@bobpark.org
THE UNIVERSITY OF MARYLAND
Opinions are the author's and are not necessarily shared by the University, but they should be.