A comprehensive review of the uses and interpretation of anthropometric references undertaken by WHO in the early 1990's concluded that new growth curves were needed to replace the existing international reference. To develop new standards, a multi-country study was carried out to collect primary growth data and related information from 8440 healthy breastfed infants and young children from diverse ethnic backgrounds and cultural settings (Brazil, Ghana, India, Norway, Oman and the USA). The first set of growth standards (length/ height-for-age, weight-for-age, weight-for- length, weight-for-height