How is epidemiology best defined?

Epidemiology is best defined as the study of how diseases affect populations. This field focuses on understanding the distribution, patterns, and determinants of health and disease conditions in specific populations. Epidemiologists seek to identify risk factors for disease and targets for preventive healthcare. By examining how diseases spread, who they impact, and what factors may contribute to their spread or severity, epidemiologists can inform public health interventions and policies aimed at improving health outcomes and reducing the incidence of diseases.

While public health policies, healthcare costs, and environmental health risks are important aspects of overall public health, they do not encapsulate the core purpose of epidemiology, which centers specifically on understanding disease dynamics within populations.