Using census data to estimate old-age mortality for developing countries

Old-age mortality accounts for large fractions of death. Yet for many developing countries, old-age mortality are often only referred by model life tables using mortality data at young ages, or sometimes at young and adult ages; and reliable estimates of old-age mortality using data collected from old-age population can hardly be found. Based on the fact that migration is rare and death risk is high at old ages, this paper proposed a method, namely the Census method, to estimate old-age mortality, using census data on old-age population. The Census method aims to eliminate the effects of age-reporting errors, and is composed of three models. The first model is the variable-r method that converts the census populations into the person-years of the underlying stationary population. The second is an adjustment model, which uses a common relationship between the survival ratios that is found in model life tables to eliminate the effects of age-reporting errors in censuses. And the third is the extended Gompertz model, which estimates the number of survivors at exact ages of the underlying stationary population based on the commonly observed mortality pattern. Examples are provided using census data from developing countries in Africa and Asia.