A Comparative Assessment of the Extent of Errors in the Age and Sex Data of Nigerian Population Censuses of 1991 and 2006

Nigeria’s census history began in 1866; during the intervening period to date, Nigeria has had 12 censuses. Using age in single years, the census data were subjected to tests of quality by using known quality tests available. The quality of Nigeria’s most recent censuses (1991 and 2006) was assessed using the following indices to assess the extent of errors: sex and age ratios, UN joint score, Whipple’s index, modified Whipple’s index, Myers’ index and index preference. The results of these assessment showed that the quality of the censuses data are comparable to some African censuses results obtained in the 1970s and 1980s. It is thus concluded that the quality Nigeria’s age and sex data were poor.