title: A comparison of the National Center for Health Statistics and new World Health Organization growth references for school-age children and adolescents with the use of data from 11 low-income countries.
abstract: BACKGROUND
  In 2007 new World Health Organization (WHO) growth references for children aged 5-19 y were introduced to replace the National Center for Health Statistics (NCHS) references.
  
  
  OBJECTIVE
  This study aimed to compare the prevalence of stunting, wasting, and thinness estimated by the NCHS and WHO growth references.
  
  
  METHODS
  NCHS and WHO height-for-age z scores were calculated with the use of cross-sectional data from 20,605 schoolchildren aged 5-17 y in 11 low-income countries. The differences in the percentage of stunted children were estimated for each year of age and sex. The z scores of body mass index-for-age and weight-for-height were calculated with the use of the WHO and NCHS references, respectively, to compare differences in the prevalence of thinness and wasting.
  
  
  RESULTS
  No systematic differences in mean z scores of height-for-age were observed between the WHO and NCHS growth references. However, z scores of height-for-age varied by sex and age, particularly during early adolescence. In children for whom weight-for-height could be calculated, the estimated prevalence of thinness (WHO reference) was consistently higher than the prevalence of wasting (NCHS reference) by as much as 9% in girls and 18% in boys.
  
  
  CONCLUSIONS
  In undernourished populations, the application of the WHO (2007) references may result in differences in the prevalence of stunting for each sex compared with results shown when the NCHS references are used as well as a higher estimated prevalence of thinness than of wasting. An awareness of these differences is important for comparative studies or the evaluation of programs. For school-age children and adolescents across all ranges of anthropometric status, the same growth references should be applied when such studies are undertaken.
authors.affiliation: Centre for Global Health and Human Development, School of Sport, Exercise and Health Sciences, Loughborough University, Leicestershire, UK. e.k.rousham@lboro.ac.uk
authors.forename: Emily K
authors.initials: EK
authors.lastname: Rousham
authors.forename: Natalie
authors.initials: N
authors.lastname: Roschnik
authors.forename: Melba Andrea B
authors.initials: MA
authors.lastname: Baylon
authors.forename: Emily A
authors.initials: EA
authors.lastname: Bobrow
authors.forename: Mavzuna
authors.initials: M
authors.lastname: Burkhanova
authors.forename: M Gerda
authors.initials: MG
authors.lastname: Campion
authors.forename: Teresita
authors.initials: T
authors.lastname: Adle-Chua
authors.forename: Tedbabe
authors.initials: T
authors.lastname: Degefie
authors.forename: Caroline
authors.initials: C
authors.lastname: Hilari
authors.forename: Humphreys
authors.initials: H
authors.lastname: Kalengamaliro
authors.forename: Tamiru
authors.initials: T
authors.lastname: Kassa
authors.forename: Fadima
authors.initials: F
authors.lastname: Maiga
authors.forename: Bonifacio J
authors.initials: BJ
authors.lastname: Mahumane
authors.forename: Mary
authors.initials: M
authors.lastname: Mukaka
authors.forename: Fatimata
authors.initials: F
authors.lastname: Ouattara
authors.forename: Amado R
authors.initials: AR
authors.lastname: Parawan
authors.forename: Moussa
authors.initials: M
authors.lastname: Sacko
authors.forename: David W
authors.initials: DW
authors.lastname: Patterson
authors.forename: Gaston
authors.initials: G
authors.lastname: Sobgo
authors.forename: Ikhtiar Uddin
authors.initials: IU
authors.lastname: Khandaker
authors.forename: Andrew
authors.initials: A
authors.lastname: Hall
mesh_terms: D000293:Adolescent; D000328:Adult; D001827:Body Height; D015992:Body Mass Index; D002648:Child; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D005260:Female; D006130:Growth Disorders / Q000453:epidemiology*; D006801:Humans; D008297:Male; D009309:National Center for Health Statistics, U.S.; D011203:Poverty; D015995:Prevalence; D013851:Thinness / Q000453:epidemiology*; D014481:United States; D019282:Wasting Syndrome / Q000453:epidemiology*; D014944:World Health Organization