Adult mortality estimates for small areas in Brazil, 1980–2010: a methodological approach

Abstract

BackgroundIn recent decades, life expectancy and health status have improved considerably in Brazil. Life expectancy at birth has risen from 48 years in 1960 to over 73 years in 2010. However, the country is marked by large regional and socioeconomic inequality. Due to data limitations, incomplete coverage of vital registration systems, and errors in age declaration for both population and death counts, little is known about the level and trends in adult mortality for sub-national areas. This study aimed to study the evolution of adult mortality in small areas in Brazil from 1980 to 2010, using 45q15 as a summary measure of adult mortality across small areas in Brazil. MethodsData were obtained from the mortality database available from Datasus, a vital statistics database organised by the Brazilian Ministry of Health that contains information on deaths by age, sex, and cause from 1979 to 2010. Population censuses were used to acquire the population by age and sex for 137 comparable small areas in Brazil, as defined by the National Statistics Office, for the years 1980 to 2010. We combined traditional formal demography methods, called death distribution methods, with indirect standardisation and Bayesian statistics to produce more reliable estimates of adult mortality for the 137 small areas. FindingsThe results show that data quality has improved considerably across Brazil during the period of analysis, but regional variation persists. On average, completeness of death counts increased from 80% (range 50–100) in 1980–91, to 95% (73–100) in 2000–10. Estimates of adult mortality show that more developed regions in the south and southeast parts of the country have lower mortality levels than the northeast, but there is a clear convergence process. InterpretationThis study indicates that the combination of traditional demographic methods to Bayesian statistics is a successful alternative to produce mortality estimates for small areas in Brazil. We also found a large improvement in the quality of mortality data in Brazil since 1980. Finally, we observe a convergence process on health status. FundingBrazilian National Counsel of Technological and Scientific Development (CNPq) and Minas Gerais Research Foundation (Fapemig).