Background Important differences exist in the diagnosis of malnutrition when comparing the 2006 World Health Organization (WHO) Child Growth Standards and the 1977 National Center for Health Statistics (NCHS) reference. However, their relationship with mortality has not been studied. Here, we assessed the accuracy of the WHO standards and the NCHS reference in predicting death in a population of malnourished children in a large nutritional program in Niger. Methods and Findings We analyzed data from 64,484 children aged 6–59 mo admitted with malnutrition (<80% weight-for-height percentage of the median [WH]% [NCHS] and/or mid-upper arm circumference [MUAC] <110 mm and/or presence of edema) in 2006 into the Médecins Sans Frontières (MSF) nutritional program in Maradi, Niger. Sensitivity and specificity of weight-for-height in terms of Z score (WHZ) and WH% for both WHO standards and NCHS reference were calculated using mortality as the gold standard. Sensitivity and specificity of MUAC were also calculated. The receiver operating characteristic (ROC) curve was traced for these cutoffs and its area under curve (AUC) estimated. In predicting mortality, WHZ (NCHS) and WH% (NCHS) showed AUC values of 0.63 (95% confidence interval [CI] 0.60–0.66) and 0.71 (CI 0.68–0.74), respectively. WHZ (WHO) and WH% (WHO) appeared to provide higher accuracy with AUC values of 0.76 (CI 0.75–0.80) and 0.77 (CI 0.75–0.80), respectively. The relationship between MUAC and mortality risk appeared to be relatively weak, with AUC = 0.63 (CI 0.60–0.67). Analyses stratified by sex and age yielded similar results. Conclusions These results suggest that in this population of children being treated for malnutrition, WH indicators calculated using WHO standards were more accurate for predicting mortality risk than those calculated using the NCHS reference. The findings are valid for a population of already malnourished children and are not necessarily generalizable to a population of children being screened for malnutrition. Future work is needed to assess which criteria are best for admission purposes to identify children most likely to benefit from therapeutic or supplementary feeding programs.
References
[1]
WHO Multicentre Growth Reference Study Group (2006) WHO Child Growth Standards: Length/height-for-age, weight-for-age, weight-for-length, weight-for-height and body mass index-for-age: Methods and development. Geneva: WHO.
[2]
de Onis M, Onyango AW, Borghi E, Garza C, Yang H (2006) Comparison of the World Health Organization (WHO) Child Growth Standards and the National Center for Health Statistics/WHO international growth reference: implications for child health programmes. Public Health Nutr 9: 942–947.
[3]
Seal A, Kerac M (2007) Operational implications of using 2006 World Health Organization growth standards in nutrition programmes: secondary data analysis. BMJ 334: 733.
[4]
World Health Organization.Country Profiles: Niger. Available: http://www.who.int/countries/ner/en/. Accessed 5 October 2007.
[5]
National Institute of Statistics (INS), Niger and Macro International Inc. (2007) Demographic Health Survey/Multiple Indicator Cluster Survey 2006 (DHS/MICS III) Preliminary Report. Calverton (Maryland): INS and Macro International.
[6]
National Institute of Statistics (INS), Niger, United Nations Children's Fund and the World Food Programme (2007) Survey of mortality and nutrition among children aged 6–59 mo in Niger, October–November 2006. New York: UNICEF.
[7]
World Health Organization; World Food Programme; United Nations. Standing Committee on Nutrition; UNICEF (2007) Community-based management of severe acute malnutrition. A joint statement by the World Health Organization, the World Food Programme, the United Nations System Standing Committee on Nutrition and the United Nations Children's Fund. Geneva: WHO.
[8]
DeLong ER, DeLong DM, Clarke-Pearson DL (1988) Comparing the areas under two or more correlated receiver operating characteristic curves: a nonparametric approach. Biometrics 44: 837–845.
[9]
Prudhon C, Briend A, Laurier D, Golden MH, Mary JY (1996) Comparison of weight- and height-based indices for assessing the risk of death in severely malnourished children. Am J Epidemiol 144: 116–123.
[10]
Briend A, Dykewicz C, Graven K.Show (1986) Usefulness of nutritional indices and classifications in predicting death of malnourished children. BMJ 293: 373–375.
[11]
Myatt M, Khara T, Collins S (2006) A review of methods to detect cases of severely malnourished children in the community for their admission into community-based therapeutic care programs. Food Nutr Bull 27: S7–S23.
[12]
Bern C, Nathanail L (1995) Is mid-upper-arm circumference a useful tool for screening in emergency settings. Lancet 345: 631–633.
[13]
Mei Z, Grummer-Strawn LM, de Onis M, Yip R (1997) The development of a MUAC-for-height reference, including a comparison to other nutritional status screening indicators. Bull World Health Organ 75: 333–341.
[14]
de Onis M, Yip R, Mei Z (1997) The development of MUAC-for-age reference data recommended by a WHO Expert Committee. Bull World Health Organ 75: 11–18.
[15]
Briend A, Zimicki S (1986) Validation of arm circumference as an indicator of risk of death in one to four year old children. Nutr Res 6: 249–261.
[16]
Briend A, Garenne M, Maire B, Fontaine O, Dieng K (1989) Nutritional status, age and survival: the muscle mass hypothesis. Eur J Clin Nutr 43: 715–726.
[17]
Briend A, Wojtyniak B, Rowland MGM (1987) Arm circumference and other risk factors in children at high risk of death in rural Bangladesh. Lancet 725: 27.
[18]
Lapidus N, Minetti A, Djibo A, Guerin PJ, Gaboulaud V, et al. (2009) Risk factors for mortality among children admitted to a large-scale nutritional program in Niger, 2006. PLoS One. e4313.. doi:10.1371/journal.pone.0004313.
