Validity of the skinfold equation using doubled skinfold thickness at triceps

BACKGROUND: The skinfold equation opens to the public on CASIO Co.'s website; it may be useful for home-visit rehabilitation settings as long as it is reliable. The purpose of this study was to examine the measurement agreements in percent body fat between the skinfold equation and bioelectrical impedance analysis. The study was conducted at the Department of Physical Therapy, Tokoha University, Hamamatsu, Japan. Study participants were 23 women (20.4 +/- 0.29 years) and 23 men (20.3 +/- 0.29 years). Cross-sectional and correlative study between two methods were analyzed to evalu-ate percent body fat.METHODS: The relationship of percent body fat was examined between the skinfold equation and bioelectrical imped-ance analysis.RESULTS: There was a significant correlation (r=0.53, P<0.001) but a poor agreement of percent body fat between the skinfold equation and bioelectrical impedance when the skinfold thicknesses at triceps and subscapular were summed and put into the skinfold equation in the skinfold equation's original way. But both a good correlation and a good agreement of percent body fat were achieved between the two methods only when the skinfold thickness at triceps was doubled and put it into the equation (r=0.67, P<0.001; bias: 0.68%, 95% limit of agreements:-9.72-11.08).CONCLUSIONS: The skinfold equation was reliable when it used only doubled skinfold thickness at triceps.

Automated summary

The study found that there was a good correlation and agreement in percent body fat between skinfold equation and bioelectrical impedance analysis when only the skinfold thickness at triceps was doubled and put into the equation.