1. The ability of a study to demonstrate an association if one exists is known as: A) inference. B) quantification. C) power. D) estimation. 2. The example of polio and spongy tar demonstrated: A) a causal association, indirect. B) a causal association, direct. C) an association, inverse. D) an association, spurious. 3. Coronary heart disease is an example of a disease that illustrates: A) necessary and sufficient causality . B) neither necessary nor sufficient causality. C) sufficient but not necessary causality. D) necessary but not sufficient causality . 4. Randomized controlled trials include: A) prophylactic trials. B) therapeutic trials. C) clinical trials. D) All of these are correct. 5. Randomized controlled trials contain which of the following components? A) Rigorous inclusion and exclusion criteria B) Blinding or masking to prevent bias C) Comparable measurement of outcomes in treatment and control conditions D) All of these are correct. 6. Which of the following involves the formal adoption of the policies, programs, and procedure