Weight for age standard deviation (according to WHO)
The measures above were calculated using the new Child Growth Standards released by the World Health Organization on April 27 2006. The new Standards are the result of an intensive study initiated by WHO in 1997 to develop a new international standard for assessing the physical growth nutritional status and motor development in all children from birth to age five. WHO and its principal partner, the United Nations University, undertook a Multi-centre Growth Reference Study which is a community-based, multi-country projects involving more than eight thousand children from Brazil, Ghana, India, Norway, Oman, and the United States of America. The measures are presented with two implied decimal places (no decimal points are included in the data file). To produce the actual measure, divide the variable by 100. If either the weight or the height of the child is missing then all of the above measures are set to the missing code 9999 or 99999. If either the height or the weight is outside of the acceptable range for the calculation of these measures then all of the above measures are set to code 9998 or 99998.