From the CDC re: Why the change?
"Why use WHO growth standards for infants and children ages 0 to 2 years of age in the U.S?
?The WHO standards establish growth of the breastfed infant as the norm for growth.
Breastfeeding is the recommended standard for infant feeding. The WHO charts reflect growth patterns among children who were predominantly breastfed for at least 4 months and still breastfeeding at 12 months.
?The WHO standards provide a better description of physiological growth in infancy.
Clinicians often use the CDC growth charts as standards on how young children should grow. However the CDC growth charts are references; they identify how typical children in the US did grow during a specific time period. Typical growth patterns may not be ideal growth patterns. The WHO growth charts are standards; they identify how children should grow when provided optimal conditions.
?The WHO standards are based on a high-quality study designed explicitly for creating growth charts.
The WHO standards were constructed using longitudinal length and weight data measured at frequent intervals. For the CDC growth charts, weight data were not available between birth and 3 months of age and the sample sizes were small for sex and age groups during the first 6 months of age.
Why use CDC growth charts for children 2 years and older in the U.S.?
?The CDC growth charts can be used continuously from ages 2-19. In contrast the WHO growth charts only provide information on children up to 5 years of age.
?For children 2-5 years, the methods used to create the CDC growth charts and the WHO growth charts are similar."
I've been doing this for about 1 yr now and it does seem to reflect more "normal" pattern--With the WHO charts I don't see that drop off in weight at 9 mo nearly as often---and by using cm instead of inches to measure kids my length charts make so much more sense. Using the small unit of measurement just gives more accurate results. And I, too, HATE the 3rd and 97th percentiles on those charts and dropped them off the charts I made. I much prefer 5-95... short, sweet, easy to read.
Will be looking at VIPER shortly.
Kathy
