Which adjustment method uses a standard population and known age-specific death rates to derive an expected number of deaths?

• A. Direct age adjustment
• B. Indirect adjustment
• C. Crude rate
• D. Standardized rate

Answer: (A)

Direct age adjustment uses a fixed standard population and the age-specific death rates from the population being studied to calculate the expected number of deaths in that standard population. By applying each age-specific rate to the corresponding age-group size in the standard population and summing, you get the total expected deaths. This yields an age-adjusted rate that lets you compare mortality across populations with different age structures because the comparison is made against the same standard distribution. In short, you’re transferring the study’s age-specific risks onto a common population, so differences reflect factors other than age distribution.