What type of study design is characterized by comparing patients who died from coronary heart disease with living controls?

The study design that involves comparing patients who died from a specific condition, such as coronary heart disease, with living controls is a case-control study. This design is particularly useful for identifying potential risk factors or causes of a condition by looking backward in time. In a case-control study, individuals with the outcome of interest (in this case, those who died from coronary heart disease) are identified and compared to a control group (those who are alive and do not have the disease). Researchers then assess the past exposure history or characteristics of both groups to determine if certain factors were more prevalent among those who died compared to those who survived.

Such a design is efficient for studying rare outcomes, like mortality from coronary heart disease, because it enables researchers to quickly identify high-risk individuals and analyze factors associated with their disease outcome without needing to wait for patients to develop the disease over time, as would be necessary in cohort studies. In contrast, cohort studies follow a group over time to see who develops the outcome, which does not fit the scenario of comparing deceased individuals to living controls at a single point in time.