Hospital morbidity in early life in relation to certain maternal and foetal characteristics and events at delivery.

Using a system oflinked medical records (Acheson, 1964), it is possible not only to accumulate and to correlate information about successive events as they occur to individuals, but to bring together information about different members ofa family (Newcombe, Kennedy, Axford, and James, 1959; Newcombe, 1964). This study exemplifies a simple application of this approach in which information about two classes of individual related by blood (mothers and their babies) has been brought together from five separate categories of medical record for a defined population at risk. An analysis has been made of the in-patient hospital morbidity experienced during 1962 of 5,901 babies born in that year to mothers resident at the time of delivery in the City of Oxford, Oxfordshire (except Henley Municipal Borough and Rural District Council), and Abingdon Municipal Borough and Rural District in Berkshire. This excludes 147 babies who were stillborn or who died before discharge from the maternity hospital in which they were born, and 379 babies who were born to resident mothers in hospitals outside the area for whom information about the relevant pregnancy and confinement were lacking. For the remainder, information was brought together from the following sources: Baby: Birth certificate. Hospital discharge summaries (if any). Death certificate (if any).