United Nations Children's Fund (UNICEF). 2009. Statistics and
Monitoring. New York: UNICEF. Available online at:
http://www.unicef.org/statistics/ Children undernourished is the
percent of children under 5 who are moderately or severely
underweight. A moderately underweight child is defined as having
a weight-for-age ratio that is minus 2 standard deviation from
the median, while a severely underweight child is minus 3
standard deviations from the median. The median is derived from
an international reference population defined by the World
Health Organization. The source of the data comes from several
household surveys developed and implemented by UNICEF as well as
official national data reported to WHO.