children aged 11-14 (Safrit, 1990). The technical error of measurement for subscapular skinfold varies from 0.88 to 1.16 mm for intraobserver error and from 0.88 to 1.53 mm for interobserver error (Harrison et al., 1988). For triceps skinfold, the technical error of measurement ranges from 0.4 to 0.8 mm for intraobserver error and from 0.8 to 1.89 mm for interobserver error (Harrison et al., 1988).

The triceps and subscapular skinfolds are the most widely used in growth studies, and national reference data were developed by using the samples included for BMI in the CDC 2000 growth charts (Addo and Himes, 2010). Skinfolds can be and have been measured on any number of bodily sites. A key is standard definition and location of the sites and proper marking of the sites prior to application of the skinfold calipers. As noted earlier, ratios of skinfolds measured on the trunk to those measured on the extremities are commonly used to estimate relative subcutaneous fat distribution, which has been related to chronic disease risk factors in youth.

ADMINISTRATIVE FEASIBILITY

When selecting fitness test items, an important criterion is the feasibility and practicality of the measures. The committee evaluated the feasibility and practicality of body composition measures assuming that they would be implemented by trained personnel as recommended in this report.

The measurements recommended for inclusion in a youth fitness test battery are height, weight, waist circumference, and triceps and subscapular skinfolds. All of these measurements can be taken reasonably quickly. The selected measurements, however, are not free of potential motivational or self-esteem influences; self-esteem may be affected by the interpretation of results for estimated body composition. For this reason and to protect privacy, waist circumference and subscapular skinfold thickness should not be assessed in group settings. It is assumed that appropriate space (e.g., a nurse’s office) would be available to ensure the privacy of the measurement process since measurement of skinfolds and waist circumference requires exposure of the trunk to allow the test administrator to access the subscapular area on the back and the waist. This setting also would minimize the potential for embarrassment when two test administrators are needed in the room (see below).

Equipment needed to measure body composition using the tests recommended above includes a stadiometer, a scale, skinfold calipers, and a tape measure. The NHANES measurement techniques are presented in Annex 4-1 as an example of commonly used methodology for indicators of body composition. As noted there, these anthropometric measurements, while not difficult, are highly error-prone. To avoid error, only high-quality equipment should be used, and test administrators should have the necessary



The National Academies | 500 Fifth St. N.W. | Washington, D.C. 20001
Copyright © National Academy of Sciences. All rights reserved.
Terms of Use and Privacy Statement