Corpulence index
The Corpulence Index (CI) or Ponderal Index (PI) is a measure of leanness of a person[1] calculated as a relationship between mass and height.[2] It was first proposed in 1921 as the "Corpulence Index" by Rohrer and hence also known as Rohrer's Index.[3] It is similar to the body mass index, but the mass is normalized with the third power of body height rather than the second power.[4]
For a baby, it is calculated as
with 
in kg (kilograms) and 
in m (meters), giving a measure with the same dimensions as density. The corpulence index yields valid results even for very short and very tall persons.[6] Because of this property, it is most commonly used in pediatrics.[7][8] The normal values for infants are about twice as high as for adults, which is the result of their relatively short legs.[citation needed] It does not need to be adjusted for age after adolescence.[4]
The corpulence index is variously defined (the first definition should be preferred due to the use of SI-units kg and m) as follows:
| Formula | Units for mass (body weight) |
Units for height (or length) |
Values corresponding to "normal" BMI in a 180 cm tall person |
|---|---|---|---|
 [8] |
kilograms | metres | 10.3 to 13.9, 24 for 12-month-old infant[7] ~12 for those 12-year-old or older.[4] |
 [7] |
grams | centimetres | 2.4 for 12-month-old infant |
![\text{CI}=1000\times\frac{\sqrt[3]{mass}}{height}](/w/images/math/0/0/8/0082da2328a513ff80062d498f6bb0dc.png) [2] |
kilograms | centimetres | 21.75 to 24.0[9] |
![\text{CI}=100\times\frac{\sqrt[3]{mass}}{height}](/w/images/math/d/f/4/df4dac1b04c0603f8f3e9843862120e4.png) [10] |
kilograms | centimetres | 2.175 to 2.4 |
![\text{CI}=\frac{height}{\sqrt[3]{mass}}](/w/images/math/f/a/a/faa0e24469a94437fe2f8b0695297143.png) [1] |
pounds | inches | 12.49 to 13.92 |
Significance
- It plays a role in assessing whether the intrauterine growth restriction of a child is symmetrical or asymmetrical.[11]
- CI has been shown to have higher sensitivity, specificity, positive predictive value, and negative predictive value than BMI.[4]
- Body adiposity index
See also
References
- ↑ 1.0 1.1 Foods and Nutrition Encyclopedia, Audrey H. Ensminger, Marion Eugene Ensminger. p. 1645
- ↑ 2.0 2.1 EXSS 323: LAB 1 - BIOMECHANICS TOOLS: Computers, Algebra and Trig Oregon State University
- ↑ http://www.wisegeek.com/what-is-the-ponderal-index.htm
- ↑ 4.0 4.1 4.2 4.3 Lua error in package.lua at line 80: module 'strict' not found.
- ↑ Lua error in package.lua at line 80: module 'strict' not found.
- ↑ Lawrence F. Ditmier: New Developments in Obesity Research. Nova Science Publishers, Hauppauge, New York 2006, ISBN 1-60021-296-4[page needed]
- ↑ 7.0 7.1 7.2 Lua error in package.lua at line 80: module 'strict' not found.
- ↑ 8.0 8.1 ACC/SCN NUTRITION POLICY PAPER No. 19 - Glossary by Lindsay H. Allen and Stuart R. Gillespie
- ↑ The source quoted (Oregon State University) states that typical healthy PI values range between 20 and 25.
- ↑ Medical Dictionary University of Newcastle upon Tyne
- ↑ Lua error in package.lua at line 80: module 'strict' not found.
External links
- Corpulence Index app for Android
- Corpulence Index app for Apple
- Online Ponderal Index Calculator, which uses the first definition.
- Ponderal Index Calculator, which uses metric values. (German site)
