(Bumping this old thread because I just came across an article by Dr Mercola which nicely illustrates the quality of his research.)
In this Mercola article:
http://articles.mercola.com/sites/articles/archive/2013/05/21/raw-milk-sales.aspx
Dr Mercola says:
"CDC data[
3] shows there are about 412 confirmed cases of people getting ill from
pasteurized milk each year, while only about 116 illnesses a year are linked to raw milk."
Dr Mercola quotes this statistic to support his argument that raw milk is more healthful than pasteurized milk. However, one caveat that occurs to us is, his statistic is meaningless until we know how many people drink pasteurized milk versus how many drink raw milk. The footnote [3] leads to this URL at the Centre for Disease Control:
https://www.cdc.gov/foodsafety/rawmilk/rawmilk-outbreaks.html
On this CDC site we read:
"Raw milk was much more likely to cause outbreaks than pasteurized milk."
Unlike Dr Mercola, the CDC has compared the percentage of raw-milk-drinkers who get sick with the percentage of pasteurized-milk-drinkers who get sick, and this comparison leads them to their conclusion.
So Dr. Mercola is claiming that raw milk is safer, and wants us to believe that the CDC, a reputable authority, backs up his claim. But when we go to the CDC, we find that it says the exact opposite of what Dr. Mercola is telling us. In order to make the data fit his hypothesis, Dr. Mercola is inviting us to make an elementary statistical error, comparing absolute figures from populations of very different sizes.