Epidemiological studies are research investigations that focus on the distribution and determinants of health-related events in specific populations. These studies help identify risk factors for diseases and understand how they spread, which can inform public health strategies. There are various types of epidemiological studies, including cohort studies, case-control studies, and cross-sectional studies. Each type has its own methods for collecting and analyzing data, allowing researchers to draw conclusions about health trends and the effectiveness of interventions in populations.