Posted by
Andrews on Thursday, April 16, 2009 6:31:44 PM
I was watching a rerun of Gordon Ramsey's
F Word and was surprised at the theory that men's sperm counts had declined over the past 50 years. of course this was blamed on toxins and poor diet. However, as refrigeration, food shipment and diet in general has improved world wide in the past 50 years, I find that absurd. Nor do I subscribe to the "increasing toxins" theory, as I explained before, I tend to think that more often is the result of better tests, not increasing poisons.
But there is another question I have about these numbers. What was the testing technology 50 years ago (in 1959), and how many men were being tested? If the test group was relatively small, or selected from, say, first world men who were both affluent and health conscious, while the current group came form a wider range of social classes, obviously the numbers could be affected by that alone. Similarly, what technology was used to examine the sperm half a century ago? Could they detect all the motility and shape problems we find today? Or would sperm considered defective today have passed in the past?
And that, in the end, is what this test reminded me, we need to look carefully before comparing the past to the present. Many scares are nothing more than improving technology discovering things that were always present. As toxins in parts per billion concentrations were always present, we just didn't find them until sometime int he 1980's, when it became a cause for all sorts of scare reports about "new" toxin infiltrations.
Before we believe such scares, it would be nice to have all the information, including how the two numbers were established and how the technology has changed.
POSTSCRIPT
There are many previous posts on this same topic, and badly interpreted science in general.You can read "
Statistical Artifacts", "
The World's Most Stupid Bureaucrat", "
Rejecting "Peak Oil"", "
Sampling Changes and Fictional Trends", "
Correlation and Causation Revisted", "
Once Again, Confused by Our Own Data", "
Health Care Deceptions", "
Historic Myopia", "
More About the Hockey Stick Graph", "
The Failure of Peer Review", "
Allergies", and "
A Dearth of Common Sense", to find out more about my thoughts on how improving testing and observation often create meaningless scares, as well as the many ways data can be misrepresented to reach a given conclusion. These posts also contain links to many other, older posts on the same topics.