Premature babies sub-study (1947)
London School of Economics
In 1947 a sub-sample comprising all 676 'premature' babies (of birth weight 5.5 lbs or less) and a set of controls were contacted. The controls were chosen from the same or nearby Local Health Authority areas and matched for sex, birth order, maternal age, social class and other unspecified social circumstances. In total, 1,362 people were contacted. There were asked questions on the details of the delivery, post-natal care and the health of the baby.
13 months - 4 years 11 months