Death registration and mortality trends in Australia 1856–1906

Abstract

Analyses of national mortality data in Australia generally do not examine the period before the formation of the Commonwealth Bureau of Census and Statistics in 1905. Yet detailed information on death and its causes is available from the beginning of civil registration in the colonies in the mid-nineteenth century, and in the case of Tasmania, as far back as 1838. By 1856, all colonies had enacted legislation for the compulsory registration of births, deaths and marriages. Between 1856 and 1906, more than 1.75 million deaths were registered in Australia. Annual summaries or ‘abstracts’ of mortality were published by colonial Registrars and Statists, containing information on age, sex and causes of death. Although not without methodological problems, these abstracts can be compiled to allow for the examination of the course of all-cause and cause-specific mortality in Australia, a period of great epidemiological change. The age-standardised rate of all-cause mortality peaked at around 2,000 per 100,000 population in 1860—a year of fearsome epidemics. An important turning point occurred in 1885, after which mortality declined steadily and with less annual variation. The death rate fell from 1,600 in 1885 to under 1,000 in 1906, a fall of one-third over two decades. Life expectancy at birth rose from 43 years for males and 46 for females in the 1850s, to 47 and 51 in the 1880s, and 54 and 58 in the 1900s. More than half of the improvement was contributed by the reduction of under-5 mortality. Two key components were declines in infant deaths from gastrointestinal infections, and in tuberculosis mortality among young adults. Cause-of-death data allow for the measurement of epidemiological transition—the replacement of infectious diseases by chronic diseases over time as mortality declined. Although there were changes in the contribution of specific causes of death such as gastrointestinal infections and tuberculosis, the relative contribution to total mortality of communicable diseases, non-communicable diseases and injuries remained largely unchanged. To that end, there was little evidence of epidemiological transition during the period. With scientific medicine largely absent, social and environmental factors—the conditions in which people live, grow, work and age—emerge as important determinants of mortality during this period. Deaths graded by occupation and by a socioeconomic index of area reveal a social gradient. Degradation of the physical environment through urbanisation and public health improvements in the form of clean water and sanitation were key determinants of mortality. Show more