A critical review of international mortality data.

Mortality data have become increasingly important not only in health related studies but also in development studies as a whole. The demand for data on life expectancy and the infant mortality rate is met by five publications-the UN Demographic Yearbook, World Population Prospects, World Development Report, World Population Trends and Policies Monitoring Report, and World Population. Within these statistical publications, life expectancy and the infant mortality rate are available for nearly every country each year. However, recent empirical information on mortality in most developing exists only for a handful of countries. The estimates published in the World Development Report and World Population Prospects are based on old empirical data updated with assumed rates of improvement in mortality. Neither of these sources provide technical notes explaining the original data source, estimation technique, and updating model used. Fortunately, two sources, the World Population Trends and Policies Monitoring Report and World Population, publish only empirically based data clearly identifying source, year of applicability, and estimation technique. The work in the World Development Report and the World Population Prospects could be made more useful if they provided adequate technical documentation for each estimate. At present, the Monitoring Report and World Population are the only appropriate sources for quantitative analysis of mortality or of change in mortality.