An academic medical center is coordinating a portfolio of clinical research protocols to investigate various disease etiologies and treatment efficacies. Match each research protocol described below to the most appropriate epidemiologic study design.
- Researchers identify patients with hepatic angiosarcoma from a national cancer registry and assess their historical exposure to vinyl chloride, comparing these findings against healthy individuals of similar age and demographic background.Case-control study
- A large group of healthy, asymptomatic young adults is enrolled and followed over a twenty-year period to determine how baseline physical activity levels affect the future incidence of early-onset cardiovascular disease.Prospective cohort study
- A randomized telephone survey is conducted simultaneously across a major city to estimate the current proportion of residents experiencing generalized anxiety symptoms and their concurrent use of telehealth therapy services.Cross-sectional study
- Patients with severe, medication-resistant rheumatoid arthritis are randomly assigned to receive either an experimental biologic agent or a placebo infusion, with neither the patients nor the assessing physicians aware of the treatment assignments.Randomized controlled trial
Answer
The hepatic angiosarcoma investigation is a case-control study, the long-term incidence tracking of young adults is a prospective cohort study, the one-time city-wide survey is a cross-sectional study, and the blinded biologic intervention is a randomized controlled trial.
Each research scenario perfectly aligns with the fundamental definitions of the core epidemiologic study designs: Case-control studies sort by disease, prospective cohorts track healthy people forward, cross-sectional studies measure prevalence at a snapshot in time, and randomized controlled trials actively assign clinical interventions.
Step-by-Step Solution
Key Concept
Epidemiologic Study Designs