FAQ

What are growth calculators?

Growth calculators are tools helping in comparing the growth parameters of the child with data obtained from general populations.

What is a percentile?

Percentiles rank the position of an individual by indicating what percent of the reference population the individual would equal or exceed.

What is a z-score?

A z-score is the number of standard deviations from mean. It measures how an individual relates to the average value for the reference population. A z-score has a direct relationship to percentiles. In extreme values any small change in percentiles can represent large change in z-score.

From where were the data used in growth calculators obtained?

All data were obtained from well-designed studies. CDC, Down syndrome, and intrauterine growth calculators data were obtained from populations residing in the US. WHO standards and INTERGROWTH-21st standards are multinational studies.

What should I do if my child's growth parameters are outside the proposed normal range?

Contact your child healthcare provider to help interpreting the data.

If my child's growth parameters are outside the proposed normal range, does that mean he has growth abnormality?

Indeed the growth is related to several factors other than age. Race, parents' height and weight, and several other factors may influence norms of growth in children. Birth weight and height has direct relationship to growth parameters in first few months of life. Puberty time and stage must be considered when interpreting growth data in adolescents. Contact your healthcare provider to make full exam before diagnosing growth abnormality.

Is it better to use CDC or WHO growth calculators for children?

It is recommended to use WHO growth charts for infants less than 2 years old and CDC charts for children 2 - 20 years old.

My child is 2 - 3 years old, should I use length-for-age chart or height-for-age chart?

If the measured parameter was standing height, use the height-for-age chart.
If the length is measured in recumbent child, use the length-for-age chart.

Which is better to monitor growth, weight-for-age or weight-for-height?

Weight-for-height gives better information about nutritional status, assessing weight in relation to height can be done using either BMI-for-age or weight-for-height charts.

What is height age?

Height age represents the age of a child in which the given height represents the mean value for that age. Comparing height age with chronological and bone ages helps in diagnosing the cause of short stature.

What is corrected target height?

The corrected target height, or cTH, is the expected mean final height of children based on their parents' height.