Provide an example of a classic cohort study.

• A. The Alameda County Diabetes Cohort
• B. The Copenhagen Heart Study
• C. The Framingham Heart Study
• D. The London Bus Driver Study

Answer: (C)

A classic cohort study is a prospective design that follows a defined group of people over time to see who develops a disease and how that outcome relates to exposures measured at the start and along the way. The Framingham Heart Study fits this perfectly. It began in 1948 in Framingham, Massachusetts, enrolling thousands of adults who were free of cardiovascular disease at baseline. They underwent regular medical examinations to collect data on risk factors such as blood pressure, cholesterol, smoking, and body weight, and then were followed for many years to see who developed heart disease or other outcomes. This long-running, population-based, forward-looking approach allowed researchers to observe temporal relationships—exposures measured before disease—and to identify major cardiovascular risk factors and create tools like risk scores. While other studies like the Copenhagen Heart Study or occupational cohorts have contributed valuable insights, Framingham is the quintessential example of a classic, landmark prospective cohort study that defined how we study disease risk over time.