Title Item Type No Grouping Peppa, M; Thomas, S; Kempley, S; Mangtani, P and Walker, J (2020). Codelists for: "Seasonal influenza vaccination during pregnancy and the risk of major congenital malformations in live-born infants: A 2010-2016 historical cohort study". [Collection]. London School of Hygiene & Tropical Medicine, London, United Kingdom. 10.17037/DATA.00001629.