Generational fertility convergence in England and Wales: assessing the own-child method

Ben Wilson, London School of Economics and Political Science (LSE)
Wendy Sigle-Rushton, London School of Economics and Political Science (LSE)

Research on migrant fertility frequently makes use of the own-child method to measure fertility (e.g. Cho et al. 1970, Abbasi-Shavazi and McDonald 2000, Adsera and Ferrer 2010), but it remains uncertain whether results are substantially affected by own-child measurement error (e.g. Abbasi-Shavazi 1997). This research tests the reliability of the own-child method using data from the Office for National Statistics Longitudinal Study (LS), a one per cent sample of the England and Wales population. This unique data source links individual-level 2001 Census data to births registered in England and Wales. As expected, fertility is underestimated using the own-child method, but it nevertheless appears to be a reliable measure of fertility for studying generational fertility convergence in England and Wales. Evidence of generational fertility convergence is found, particularly for women with South Asian origins. This conclusion does not change when births missed by the own-child method are included in the analysis.