What measure represents the average number of years of life that could be expected if current death rates remain constant and is used as a gauge of population health?

• A. The median age at death in a population.
• B. Represents the average number of years of life that could be expected if current death rates were to remain constant; used as a gauge of the overall health of a population.
• C. The number of deaths in children less than one year of age per 1,000 live births.
• D. The length of human life; longevity usually refers to living past the estimated life expectancy or the average age of death

Answer: (B)

Life expectancy is the average number of years a person would be expected to live if current death rates continue. This single figure captures overall mortality across all ages and serves as a broad gauge of a population’s health, since better health, living conditions, and care tend to raise the number. In this description, the measure described is life expectancy, typically reported as life expectancy at birth to indicate the expected lifespan of a newborn given current mortality.

Other ideas don’t fit as well: median age at death is simply the age by which half have died and doesn’t assume constant mortality across ages; infant mortality rate focuses only on deaths before age one per 1,000 live births; longevity is a general notion of long life, not a single population health metric.