Estimating the 2011 total fertility rate for England & Wales and Scotland using alternative data sources

It is important to estimate fertility rates as accurately as possible in order to make appropriate comparisons of fertility levels across time and space and to inform fertility projections. This paper compares estimates of the 2011 total fertility rate (TFR) for all, UK-born and non-UKborn women in England & Wales and Scotland, obtained using several data sources. The three data sources we use are vital registration (VR) data, longitudinal studies (linked census and vital events data) and census household microdata samples from the respective countries. Although estimates based on VR data are classed as official, the event and risk population information come from different sources. Surveys and census data do not suffer from this issue, but their analysis requires decisions regarding the selection of the sample and how to deal with exits and entries to the UK. We find:• TFR estimates from the census microdata tend to be closest to those from VR data, particularly for Scotland. For England & Wales, the census estimates are lower than those from VR data, especially for non-UK-born women.• The longitudinal study estimates are the lowest among the three data sources for Scotland, while for England & Wales they are lower or higher than the corresponding VR estimate with this generally depending on the precise estimation method used.• Overall, this study finds some small variation in the TFR estimates from these different sources, owing to their contrasting coverage, mode of collection and sample size.• The reasonable consistency of the census-linked data and the census household microdata with the VR estimates shows that they are an important source of information which allows the examination of subgroup differences in childbearing behaviour