Question

What is a confounding variable? Use an example to explain. What is effect modification? Use an example to explain.

Answer 1

SOLUTION:-

(a) Confounding variable:- In statistics confounding variable effects both the variable depending as well as independent variable and the outcomes doesn't lie causative pathway.

Example- If we observe the relationship between coffee and lung cancer this relation may be distorted due to smoking and non smoking so we need to consider them separately for both smokers and non smokers.

(b) Effect Modulation:- In effect modulation different sub groups have different effect of exposure . Effect modification is associated with outcomes but not the exposure.

Example:- We are testing new kind of medicine on female and male but it have effect on female but not over male.