Where do the differences in childhood mortality rates between England and Wales and Sweden originate?

The article focuses on findings of a study related to reasons for the differences in childhood mortality rates between England and Wales and Sweden. It states the significance of preventive healthcare strategies in reducing mortality in Great Britain, and mentions that excess death in 2006 were caused by differences in birthweight distribution in England, Wales and Sweden. It notes that outlook for the mortality rates in England and Wales were found better in terms of characteristics at birth.