Here's another example of misleading medical statistics example you might want to use in class. http://www.guardian.co.uk/science/2009/apr/11/bowel-cancer-soya
The report says that more soy in the diet (it doesn't say how much more) can reduce women's chance of death from bowel cancer by 30%. (Actually, it says those in the top third of soya intake had a 30% decrease in bowel cancer deaths, compared to the bottom third -- NOTE: not from the national average -- but it doesn't give any indication of how much soy each group actually ate.) So let's work the numbers. 16,600 women die from bowel cancer per year in the UK. There are about 60 million people in the UK. Half are female: 30 million. Lose the 20% children and we have 24 million women. So, the chance of dying of bowel cancers for women in any one year is: 16,600/30 million = .0007, or 7 in 10,000. A 30% reduction would lower that chance to 5 in 10,000. So (even if the causal implication that is not actually demonstrated here were correct), if increasing your soy intake by a fair bit could decrease your chances of dying by bowel cancer by 30%, that would represent a tiny reduction of just 2 in 10,000 per year. Chris -- Christopher D. Green Department of Psychology York University Toronto, ON M3J 1P3 Canada 416-736-2100 ex. 66164 [email protected] http://www.yorku.ca/christo/ ========================== --- To make changes to your subscription contact: Bill Southerly ([email protected])
