What are factors associated with an elevated frequency of a disease but not proven to be causal?

Answer 1

If you are looking for an answer for a test question for nutrition class the answer is risk factors. If you have the same worksheet I have the rest of the answers are on Wadsworths student resource glossary. Just Google "student resource glossary" and it is the first hit.

Absolutely proving causality in diseases can be very difficult due to ethical concerns. For instance, proving that smoking causes cancer was very difficult. You had population studies where individuals who smoked tended to get cancer more often, and you could sort of try to control for various factors such as age.gender, occupation, amount of exercise, diet, etc. but you couldn't prove casuality because it was impossible to control for every other difference that could have increased cancer rates. The gold standard sort of study would have been to take a group of non-smokers from households where no one smoked and randomly have half of the group smoke a pack of cigarettes a day for 20 years. After 20 years, you follow up and record the percentage with any sort of cancer. Compare the two percents, and wahla, you've got pretty conclusive evidence that smoking causes cancer. Only problem is that you've just given however many human volunteers in your study cancer. So many factors have been associated with an elevated frequency of disease but have not been proven causal.