One famous study followed a cohort of nurses over their lives, collecting data and health histories as they aged. Which would be the most appropriate categorization of this study?

Correct Answer: B

Rationale: Prospective studies monitor a group of individuals to determine if and when disease occurs. A cross-sectional study examines relationships between potential causal factors and disease at a specific time. A retrospective study compares individuals with a particular condition or disease with those who do not have the disease. A true experiment involves both an experimental group who receives an intervention and a control group who does not receive an intervention.

Correct Answer: D

Rationale: Epidemiological studies include descriptive (A), observational (B), and interventional (C) types. Qualitative study (D) is a social science method, not typically epidemiological.

Correct Answer: B

Rationale: Cohort studies (B) follow groups over time to track disease development (e.g., Framingham Study). A is snapshot, C is retrospective, D is experimental.

Correct Answer: A

Rationale: Excess mortality (A) is deaths above expected (e.g., during a pandemic). B, C, and D are broader or specific counts.

Correct Answer: A

Rationale: Controls (A) in case-control studies compare exposure in non-diseased to diseased. B is trials, C and D are cohort/cross-sectional aims.