Carefully consider the following questions. Write down your answers (1 - 2 paragraphs) for question # 1 within a word document and submit your answers to your seminar leader. Be prepared to discuss all questions during the seminar section.

1. Which study design offers the best opportunity to control for confounding -- randomized clinical trial, cohort study, or case-control study? Explain your reasoning and make examples to prove your point.
2. Suppose that in the study of pesticide use and breast cancer you wanted to evaluate the hypothesis that pesticide use varies by geographic area. Would you match on geographic area? Please, explain your answer.
3. A principle of case-control studies is that controls should be selected independently of exposure status. Under what circumstances would matching violate this principle? What can be done about this type of violation?

Questions for the Intellectually Curious:

Why is it important to distinguish between "confounding" and "confounders"? What does a 95% confidence interval assume about the presence of bias and confounding?