Evaluation of Skinfold Techniques in People with Down Syndrome: Development of a New Equation

The primary aim of this study was to evaluate the accuracy of skinfold thickness (SFT) measurements for the estimation of %Fat when compared to dual energy X-ray absorptiometry (DXA) in individuals with Down syndrome (DS). The secondary aim was to develop a new SFT-based body fat equation (SFT(NICKERSON)). SFT-based %Fat was estimated using a body fat equation from González-Agüero (SFT(G-A)) and body density conversion formulas from Siri (SFT(SIRI)) and Brozek (SFT(BROZEK)). Criterion %Fat was measured via DXA. SFT(G-A), SFT(SIRI), and SFT(BROZEK) were significantly lower than DXA (mean differences ranged from −7.59 to −13.51%; all p < 0.001). The SEE values ranged from 3.47% (SFT(BROZEK)) to 8.60% (SFT(G-A)). The 95% limits of agreement were greater than ±10% for all comparisons. Mid-axilla and suprailium were significant predictors of %Fat (both p < 0.05). %Fat SFT(NICKERSON) = 10.323 + (0.661 × mid-axilla) + (0.712 × suprailium). Age and all other skinfold sites were not statically significant in the regression model (all p > 0.05). Current findings indicate that SFT(G-A), SFT(SIRI), and SFT(BROZEK) erroneously place an individual with excessive adiposity in a normal healthy range. Accordingly, the current study developed a new equation (SFT(NICKERSON)) that can easily be administered in people with DS in a quick and efficient time frame. However, further research is warranted in this area.