[Correlation between skinfold thickness and ultrasonography in the study of subcutaneous adipose tissue in females].

The aim of this study was to verify if there is a 1:2 correlation between subcutaneous adipose tissue thickness measured by ultrasonography and skinfold caliper and if this correlation varies in function of the degree of obesity, subcutaneous fat thickness, and the area evaluated. Forty women (age 27.9 +/- 11.7 years, body mass index 28.75 +/- 5.40 Kg/m2, waist to hip ratio 0.77 +/- 0.06) underwent ultrasonographic measurement of subcutaneous adipose tissue and skinfold caliper measurement at nine different sites (bicipital, tricipital, subscapular, suprailiac, epigastric umbilical, hypogastric, gluteal, and femoral). Data analysis confirmed a significant correlation between measurements made by ultrasonography and skinfold plicometry at all sites when the patients were not subdivided according to body mass index or skinfold thickness. When they were subdivided on the basis of body mass index, a significant correlation was found for subjects with a body mass index < 30; when the index was > 30, the correlation was observed at only the subscapular and suprailiac sites, and to a lesser degree at the tricipital and femoral sites. Moreover, a highly significant correlation was found only at sites at which ultrasonographic thickness was not > 20 mm (p < 0.001) with an r value decreasing progressively from 0.685 (thickness < 10 mm) to 0.248 (thickness > 40 mm). Given the great variability of this correlation, we suggest that ultrasonography is preferable to plicometry for the measurement of fat.