Final answer:
Analytical epidemiology investigates the incidence of disease across populations, typically defined by geography, to identify patterns and risk factors, informing health policies and practices.
Step-by-step explanation:
The study design mentioned in the question refers to the practice of analytical epidemiology, which is a field within Public Health. This kind of study design is used to analyze the incidence of a disease across different cities or regions rather than focusing on individual cases. Instead of looking at singular cases, epidemiologists compare the number of new instances of a condition across larger populations defined by geography or other criteria. For example, they may compare the incidence rates of a chronic disease in different states or cities over a period of time to identify patterns, risk factors, and the spread of disease, as well as the effectiveness of public health interventions. Such studies are crucial in shaping health policies and medical practices by identifying targets for preventive healthcare and are a key component of maintaining public health.