Historical trends in the correlation of sibling deaths in infancy in the Netherlands

In this article, we study temporal, regional, and social variation in infant and childhood death clustering in The Netherlands, using data from three provinces. The data relate to children born in 90,000 marriages contracted between the beginning and the last quarter of the nineteenth century. Descriptive indicators show that death clustering was more frequent in the province of Zeeland and more common in the lower classes, and that it increased in two provinces over time. Shared frailty hazard models make it clear that the number of children who died before the birth of an index child had a negative effect on the mortality of index children, whereas earlier stillbirths and the number of children who died when the index child was at a young age had an increasing effect on the mortality of index children.