Updated March 05, 2015.

Question: What data was used to create the growth charts?

Answer: General Information

Data for the CDC Growth Charts included:

• physical measurements of stature or length, and weight from infants, children, and adolescents up to 20 years of age.
• head circumference measurements from infants and children up to 36 months of age were also used.

The measurement data were obtained from a series of national health examination surveys conducted by NCHS from 1963 to 1994 and from supplemental data sources .

These surveys and data sources included:

• the National Health Examination Survey (NHES), Cycles II and III
• the National Health and Nutrition Examination Survey (NHANES) I, II, and III
• U.S. Vital Statistics
• Wisconsin Vital Statistics
• Missouri Vital Statistics
• Fels Longitudinal Study
• Pediatric Nutrition Surveillance System

In each of the cross-sectional surveys, a national probability sample of the civilian, non-institutionalized population of the United States was examined. Survey-specific sample weights were applied to the national survey sample data to assure representation of the U.S. population according to age, gender, and racial/ethnic composition at the time the surveys were conducted. Supplemental data sources provided data for birth to 2 months of age. The large sample size in these surveys and the pooling of older data added precision for calculation of the outlying percentile estimates, especially the 3rd and 97th percentiles, to better assess children who are growing at the extremes.
Infant Data in the CDC Growth Chart Reference

For the first time, nationally representative data were used to construct the growth charts for infants from birth to 36 months of age.

Child and Adolescent Data in the CDC Growth Chart Reference

Data used to create the growth charts for children and adolescents 2 to 20 years of age were nationally representative and obtained from 5 national survey data sets.