To access this article, click on "Additional Links".OBJECTIVE: To compare the National Centre for Health Statistics (NCHS) international growth reference with the new World Health Organization (WHO) growth standards for identification of the malnourished (wasted) children most at risk of death. DESIGN: Retrospective data analysis. SETTING: A Médecins Sans Frontières (Doctors Without Borders) nutrition program in Maradi, Niger, in 2006 that treated moderately and severely malnourished children. PARTICIPANTS: A total of 53 661 wasted children aged 6 months to 5 years (272 of whom died) in the program were included. INTERVENTIONS: EpiNut (Epi Info 6.0; Centers for Disease Control and Prevention, Atlanta, Georgia) software was used to calculate the percentage of the median for the NCHS reference group, and the WHO (igrowup macro; Geneva, Switzerland) software was used to calculate z scores for the WHO standards group of the 53 661 wasted children. OUTCOME MEASURES: The main outcome measures are the difference in classification of children as either moderate or severely malnourished according to the NCHS growth reference and the new WHO growth standards, specifically focusing on children who died during the program. RESULTS: Of the children classified as moderately wasted using the NCHS reference, 37% would have been classified as severely wasted according to the new WHO growth standards. These children were almost 3 times more likely to die than those classified as moderately wasted by both references, and deaths in this group constituted 47% of all deaths in the program. CONCLUSIONS: The new WHO growth standards identifies more children as severely wasted compared with the NCHS growth reference, including children at high mortality risk who would potentially otherwise be excluded from some therapeutic feeding programs.