Certified in Public Health (CPH) Practice Exam

Case-control studies are particularly effective for studying diseases of which prevalence?

1. High prevalence

2. High validity

3. Low case fatality

4. Low prevalence

The correct answer is: Low prevalence

Case-control studies are particularly effective for studying diseases with low prevalence because of their design, which allows researchers to identify and analyze individuals with the disease (cases) and compare them with individuals without the disease (controls). This method is particularly useful for studying rare diseases or conditions, as it enables the researcher to gather sufficient data about a small number of cases without needing to follow a large population over time, which would be more challenging and resource-intensive. In such studies, researchers can retrospectively assess exposure to risk factors or potential causes among the cases and controls. This is a critical advantage when dealing with low-prevalence diseases, as it helps to focus the research efforts on a more manageable group of affected individuals, thereby enhancing the efficiency and feasibility of the study. Conversely, studying highly prevalent diseases may lead to overwhelming amounts of data that could complicate the analysis. Moreover, if a disease has a high case fatality rate, cases may not persist long enough for effective comparisons, making case-control studies less suitable. Therefore, the low prevalence of the disease aligns well with the strengths of the case-control study design, making it particularly effective in this context.