This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Social & Preventive Medicine
[{'content': 'Confounding cannot be removed by? \nSelect and explain. \nA. Assign confounders to both cases and controls, B. Stratification, C. Matching, D. All of the above', 'role': 'user'}, {'content': "Answer: D \nExplanation: All of the above REF: Park 20' edition page 68, http://en.wikipedia.org/wiki/Confounding There are various ways to modify a study design to actively exclude or control confounding variables In Case-control studies assign confounders to both groups, cases and controls, equally. In Coho studies matching is often done by only admitting ceain age groups or a ceain sex into the study population, and thus all cohos are comparable in regard to the possible confounding variable Stratification: Controlling for confounding by measuring the known confounders and including them as covariates in multivariate analyses", 'role': 'assistant'}]