In epidemiology, what is primarily studied?

In the field of epidemiology, the primary focus is on the distribution of health-related events in populations. This encompasses understanding how diseases spread, the factors that influence health outcomes, and the demographics most affected by certain health issues. Epidemiologists analyze patterns, causes, and effects of health and disease conditions in defined populations, which helps to inform public health strategies and interventions aimed at improving health outcomes.

On the other hand, while the effectiveness of new pharmaceuticals plays an important role in health care, it falls more under pharmacology and clinical research rather than the core aim of epidemiology. Similarly, studying the psychological traits of healthy individuals involves aspects of psychology and behavioral health, not the epidemiological focus on populations and health events. Lastly, nutritional habits of patients would be significant in nutritional science and dietetics; although it is relevant to public health, it is not the primary study focus of epidemiology, which emphasizes the broader patterns and determinants of health within populations.