Statistics are extremely powerful and can be dangerous. It is very easy to use numbers to show just about anything. However, even this does not tell the whole story. If a difference is found, it could be due to a common trait of the group, but it also might be another, less evident factor. I'll discuss more about epidemiology in the coming months.
Epidemiology is very useful for suggesting possible links between cause and effect.
However, Good Science then dictates that the suspected correlation be taken into the laboratory to find the mechanism that positively links cause to effect. Recognizing Bad Science Bad Science is out there, but it is often hard to recognize. To a non-scientist, the claims made by Bad Science can be convincing, and often scary. It takes considerable expertise and knowledge to recognize Bad Science for what it is. The scientific community has built up a number of methods and procedures to recognize and discredit Bad Science before allowing it to be published.