Fertility Analysis with EU-SILC: A Quantification of Measurement Bias.

Summary The European Union Statistics on Income and Living Condition (EU-SILC) database is increasingly used in demographic analysis, due to its large country coverage, the availability of harmonized socioeconomic measures and the possibility to merge partners. However, so far there exists no comprehensive analysis of the representativeness of fertility behavior reported by EU-SILC. This paper quantifies the quality of fertility measures in EU-SILC. We compare several fertility measures obtained with EU-SILC to unbiased measures from the Human Fertility Database (HFD) for several European countries, by applying a longitudinal as well as a cross-sectional perspective. We show that EU-SILC underestimates completed fertility mainly because the questionnaire does not ask about the number of children ever born to a woman/man, and we identify significant socioeconomic differentials in this measurement bias. Measures of periodic fertility behavior are biased downward mainly due to attrition, while births of order one for ages 20-29 are particularly underreported. However, we find no evidence for socio-economic differentials in attrition. Our results suggest that for the majority of European countries, Eu-SILC can be used for demographic analysis when respecting the measures of precaution mentioned in this article. These contain for example applying a retrospective approach and differentiating by rotation groups when calculating aggregate measures of periodic fertility differentiated by socio-economic groups.