Why?Why?
How?How?
What next?What next?
World Health Organization
1 year 2 years 3 years 4 years 5 years
WHO Child Growth StandardsWHO Child Growth Standards
Why?Why?
WHO Child Growth StandardsWHO Child Growth Standards
World Health Organization
NCHS/WHO international reference NCHS/WHO international reference and national referencesand national references
National Center for Health Statistics (NCHS) and WHO National Center for Health Statistics (NCHS) and WHO referencereference
recommended in 1977recommended in 1977 developed based on longitudinal data (0-3 yrs) and on 3 cross-developed based on longitudinal data (0-3 yrs) and on 3 cross-
sectional studies (older children) of American populationsectional studies (older children) of American population The infant population predominantly artificially fedThe infant population predominantly artificially fed
National growth references National growth references Mostly also non-breastfed or mixed fed children (well Mostly also non-breastfed or mixed fed children (well
documented in e.g. Czech republic)documented in e.g. Czech republic)
Source: de Onis et al. Worldwide practices in child growth monitoring. Journal of Pediatrics 2004;144:461-5.
Worldwide practices in child growth monitoring
Reference population
Reference
CountriesNumber %
NCHS/WHO 99 68Tanner 3 2Harvard 13 9Local 25 17Other 17 12Unknown 6 4
Milestones in the development of new Milestones in the development of new international growth referenceinternational growth reference
1991-19931991-1993 WHO Working Group on Infant GrowthWHO Working Group on Infant Growth
Comprehensive review shows growth patterns of healthy breastfed infants differ from the current Comprehensive review shows growth patterns of healthy breastfed infants differ from the current NCHS/WHO international reference NCHS/WHO international reference
A new growth reference is needed to improve infant health managementA new growth reference is needed to improve infant health management
The reference population should reflect health recommendations in view of the frequent use of The reference population should reflect health recommendations in view of the frequent use of references as “standards”references as “standards”
WHO Multicentre Growth Reference Study
Mean z-scores of healthy breastfed infants Mean z-scores of healthy breastfed infants relative to the NCHS/WHO referencerelative to the NCHS/WHO reference
Source: An Evaluation of Infant Growth, WHO, 1994
Source: An Evaluation of Infant Growth, WHO, 1994
Rationale for the development of new Rationale for the development of new international growth referenceinternational growth reference
The current NCHS/WHO international referenceThe current NCHS/WHO international reference is inappropriate for assessing nutritional status:is inappropriate for assessing nutritional status:
Individual infantsIndividual infants interferes with sound nutritional management of breastfed interferes with sound nutritional management of breastfed
infants thus increasing risk of morbidity and mortalityinfants thus increasing risk of morbidity and mortality
PopulationsPopulations provides inaccurate community estimates of under- provides inaccurate community estimates of under- and overnutritionand overnutrition
WHO Multicentre Growth Reference Study
Standard vs. referenceStandard vs. reference
StandardStandardPrescriptive –Prescriptive –
Showing how children Showing how children
SHOULD growSHOULD grow
Reference Reference Descriptive – Descriptive –
Showing how a sample Showing how a sample of a given population of a given population grow (regardless of its grow (regardless of its nutritional and other nutritional and other conditions)conditions)
Rationale for the development of new international growth reference
Upward bias
of reference population
childhood obesity
How?How?
WHO Child Growth StandardsWHO Child Growth Standards
World Health Organization
A Growth Curve for the A Growth Curve for the 21st Century21st Century
Nutrition for Health and DevelopmentWorld Health Organization
Geneva, Switzerland
The WHO Multicentre The WHO Multicentre Growth Reference Growth Reference
StudyStudy
Optimal NutritionOptimal Nutrition– Breastfed infantsBreastfed infants– Appropriate complementary feedingAppropriate complementary feeding
Optimal EnvironmentOptimal Environment– No microbiological contaminationNo microbiological contamination– No smokingNo smoking
Optimal Health CareOptimal Health Care– ImmunizationImmunization– Pediatric routinesPediatric routines
OptimalGrowth
Growth Reference StudyGrowth Reference StudyPrescriptive ApproachPrescriptive Approach
WHO Multicentre Growth Reference Study
Eligibility criteria of study populationEligibility criteria of study population
SES that does not constrain growthSES that does not constrain growth Altitude < 1,500mAltitude < 1,500m Low mobility target populationLow mobility target population Minimum 20% of mothers follow feeding Minimum 20% of mothers follow feeding
recommendationsrecommendations Existing breastfeeding support systemExisting breastfeeding support system Presence of collaborative institutionsPresence of collaborative institutions
WHO Multicentre Growth Reference Study
Eligibility criteria of individualsEligibility criteria of individuals
No health, environmental or economic constraints on No health, environmental or economic constraints on growthgrowth
Mother willing to follow feeding recommendationsMother willing to follow feeding recommendations Term birthTerm birth Single birthSingle birth Lack of significant perinatal morbidityLack of significant perinatal morbidity No smoking mothers (before and after delivery)No smoking mothers (before and after delivery)
WHO Multicentre Growth Reference Study
MGRS study designMGRS study design
year 1year 1 year 2year 2 year 3year 3
Longitudinal (0-24 months)Longitudinal (0-24 months)
Cross-sectional (18-71 mo)Cross-sectional (18-71 mo)
WHO Multicentre Growth Reference Study
Time schedule child anthropometryTime schedule child anthropometry
Measurement Time frame Frequency No. of visits
Birth Once 1
Weeks 2-8 Bi-weekly 4
3-12 months Monthly 10
Weight, length, head circumference
14-24 months Bi-monthly 6
3-12 months Monthly 10 Arm circumference Skinfold thicknesses 14-24 months Bi-monthly 6
WHO Multicentre Growth Reference Study
Motor developmentMotor development
Six universal motor Six universal motor
development development
milestones assessed milestones assessed
between 4 and between 4 and 18 18
months of age months of age
WHO Multicentre Growth Reference Study
WHO Multicentre Growth Reference Study
Motor Development Assessment
Sample sizeSample size
Total sample > 8,400 by combining:
– cohorts 300 newborns per site
– 1,400 children aged 18 to 71 months per site
Target of growth curves: 400 both sexes
WHO Multicentre Growth Reference Study
Measurement and Measurement and standardization protocolsstandardization protocols
Rigorous scientific standards are Rigorous scientific standards are
applied to a complex cross-cultural applied to a complex cross-cultural
field-based project. field-based project.
WHO Multicentre Growth Reference Study
WHO Multicentre Growth Reference Study
The WHO Multicentre Growth Reference Study The WHO Multicentre Growth Reference Study
Rationale, Planning & ImplementationRationale, Planning & Implementation
Food and Nutrition Bulletin
vol 25, no.1 (supplement)
March 2004
What What next?next?
WHO Child Growth Standards
World Health Organization
1990 91 92 93 94 1995 96 97 98 99 2000 01 02 03 04 2005 06 07 08 09 2010
WHA Resolution
(May 1994)
WHO Working Group on Infant Growth
WHO Working Group on Growth Reference
Protocol
WHO Multicentre Growth Reference Study
Field implementation
(July 97)
(Nov 03)
Growth Standards
2nd set
Construction and testing of growth
standards
Growth Standards 1st set: Weight-for-age, length/height-for-age, weight-for-length/ height, BMI-for-age and motor development indicators.
Growth Standards 2nd set: Arm-Circumference-for-age, Triceps skinfold-for-age,
Subscapular skinfold-for-age and Head circumference-for-age.
WHO Expert Committee recommendation
(Nov 1993)
Growth Standards
1st set
WHO Child Growth Standards TimelineWHO Child Growth Standards Timeline
WHO - MGRS / reference indicatorsWHO - MGRS / reference indicators Attained growth
weight-for-age length/height-for-age weight-for-length/height head circumference-for-age mid-upper arm circumference-for-age triceps skinfold-for-age subscapular skinfold-for-age body mass index-for-age
Velocity weight length head circumference• arm circumference• body mass index
WHO Multicentre Growth Reference Study
WHO Child Growth StandardsWHO Child Growth Standards
Innovative aspectsInnovative aspects
Prescriptive approach recognizing need for standards
Breastfed infant as normative model
International sample
Reference data for assessing childhood obesity
Velocity reference data
Link between physical growth and motor development
WHO Child Growth StandardsWHO Child Growth Standards2004-20102004-2010
Construction of standards Evaluation and field testing of provisional standards Develop WHO/MGRS software to support individual- and
population-based uses Develop training modules to guide appropriate use Review interventions to prevent/treat impaired child growth Develop roll-out strategy with partners, oversee global and
country level implementation of the new standards Adapt global monitoring system for MDG tracking
WHO Department of Nutrition for Health and Development
Strategy for promoting healthy growth Strategy for promoting healthy growth and developmentand development
Training on itsTraining on its
appropriateappropriate
use and use and
interpretationinterpretation
WHO Multicentre Growth Reference Study
Development Development
of a soundof a sound
international international
growth growth
referencereference
Clinical andClinical and
Public HealthPublic Health
InterventionsInterventions
Child survivalChild survival
Physical growthPhysical growth
Child developmentChild development
WHO Multicentre Growth Reference Study