Which statement best reflects the use of case-fatality rate?

• A. It is best used for chronic diseases.
• B. It is best used when diseases are short term.
• C. It is not applicable in epidemiology.
• D. It measures the rate of new cases.

Answer: (B)

Case-fatality rate is the proportion of people diagnosed with a disease who die from that disease within a defined time period. This makes it most informative for diseases with a short, well-defined course because outcomes (deaths) are observed within the observation window and the denominator (diagnosed cases) is clear. For chronic diseases, many patients live for long periods and outcomes may occur long after the observation period, leaving many cases unresolved and the CFR unstable or misleading. It’s not about the rate of new cases (that’s incidence), and it is a legitimate epidemiologic measure, not something that would be dismissed as inapplicable. So the best statement is that it is best used when diseases are short term.