Which statement best defines descriptive studies?

• A. They do not make inferences about associations between exposures and outcomes
• B. They always involve randomization
• C. They always use a gold standard
• D. They measure only outcomes, not exposures

Answer: (A)

Descriptive studies focus on describing patterns of health and disease in a population, including how common a condition is and how it varies by person, place, and time. They summarize distributions of exposures and outcomes but do not attempt to infer relationships between exposures and outcomes. Establishing associations requires analytic methods, comparison groups, and control for confounding, which go beyond simple descriptive description. That’s why this statement best captures what descriptive studies do.

The other ideas aren’t defining features: descriptive studies don’t involve randomization, they don’t require a gold standard measurement, and they can describe either outcomes, exposures, or both, not solely outcomes.