EXPERIMENTAL INDIGENOUS LIFE TABLES FOR 1996-2001
The Australian Bureau of Statistics (ABS) has been compiling experimental Indigenous life tables for the period 1996-2001. Mortality estimates derived from these life tables will be used to prepare experimental Indigenous population estimates and projections.
The standard approach to calculating death rates used in life tables is to divide the number of deaths in a given population by the population 'exposed to risk' during that period. Although it is considered likely that most Indigenous births and deaths are registered, a proportion of these births and deaths are not identified as ‘Indigenous’. Without complete and accurate data on Indigenous births and deaths, and accurate data on the size and structure of the Indigenous population, the standard method for calculating Indigenous death rates cannot be used.
The ABS has used a new demographic method for determining the coverage (or completeness) of Indigenous deaths obtained from Australia's death registration system. This method offers definite improvement over other indirect methods available for estimating mortality from defective data. The main advantage of this method over other methods is that it explicitly allows for the 'non-biological' growth of the Indigenous population (i.e. growth which is unexplainable by demographic factors) between the two adjacent censuses to be taken into account. Using this method, the ABS calculates the consistency of Indigenous death registrations for the 1991-1996 and 1996-2001 intercensal periods relative to population estimates at the beginning and end of each five year period. A consistency factor, assumed to be constant at each age group, is applied to the observed age-specific death rates which are then used for the calculation of the Indigenous life tables.
The ABS has assessed the sensitivity of the method to assumptions about the level and age distribution of the non-biological growth in the Indigenous population. The sensitivity analysis was restricted to the 1996-2001 period only. Results obtained from the sensitivity analysis show that life expectancy estimates derived under various assumptions vary widely between states/territories and Australia.
A Demography Working Paper and the experimental Indigenous population estimates and projections will be released in July 2004.
For more information please contact Shahidullah on (02) 6252 5129 or firstname.lastname@example.org