Population modeling for a small area: a comparative analysis of census and demographic surveillance system data in South Africa
Makandwe Nyirenda, University of Kwazulu-Natal
Victoria Hosegood, London School of Hygiene and Tropical Medicine (LSHTM)
Tom A. Moultrie, University of Cape Town
Accurate and reliable small-area statistics are useful for planning and decision making. However, such data are usually not rigorously interrogated for their reliability. As a result little is known about the potential bias of using such data as a basis for decision-making. This paper is based on a comparative analysis of census and demographic surveillance data, as basis for resource allocation and development planning at a local level. For the study area the published census population undercounted the true population by between 15-20 per cent, but this undercount was not evenly distributed by age and sex. Despite the almost universal participation rates of the studied population in the longitudinal demographic surveillance, we still find evidence of under enumeration of children. We show that census data after adjustment may bear no resemblance to the actual local area population. Possible sources of bias in census data and their consequences are discussed.