Infants

The UK Department of Health survey data were combined for the years 2003-2005, for supine length and weight. The detail dimensions are from the HUMAG study of 1998, and have been updated by the difference in supine length, which is about 5% greater.

The increase is probably a function both of sampling (which is particularly good in the government health surveys) and of the general trend of increasing size.

Weight was about 8% bigger in the DoH data than HUMAG, but because of uncertainty this increase has not been applied to the detail data. Measuring infants is very difficult and tolerances are large - for example the American NHANES infants are similarly heavier than HUMAG but their upper arm circumferences are actually slightly smaller.

Length and weight data from HUMAG was used (with other UK data from this period) to develop the UK90 infant growth charts which are still in use.