Confounding occurs when the effect of the primary exposure on the outcome is mixed with the effect of another variable. It can be controlled through:
1. Randomization: Distributes confounders equally between study groups. 2. Restriction: Limits the study to individuals who fall within a certain category of the confounding variable. 3. Matching: Pairs cases and controls based on confounding variables. 4. Statistical Adjustment: Uses methods like multivariable regression to account for confounders.
