The primary function of epidemiology in public health is studying the distribution and determinants of diseases in populations. This involves identifying patterns, causes, and effects of health and disease conditions to inform prevention strategies and control measures. Unlike direct patient care or surgical innovation, epidemiology focuses on population-level data to guide public health decisions and policies. Understanding these factors enables effective intervention planning to reduce disease burden and improve community health outcomes.

Reference: *Epidemiology: Beyond the Basics*, Moyses Szklo, 4th Edition.