Reliability of Measuring Subcutaneous Fat Tissue Thickness Using Ultrasound in Non-Athletic Young Adults

Obesity is a major health burden worldwide. A method of assessing uncompressed subcutaneous adipose tissue thickness (USATT) using ultrasound is widely used in sports medicine. However, studies on the reliability of the method in non-athletic people are lacking. We aim to determine the reliability of the human observer in measuring the USATT in non-athletic people.

Two young non-athletic, volunteers, having normal body mass, one male (24 years, BMI=21.6 kg/m2) and one female (31 years, BMI=20.73 kg/m2) were measured by 15 observers, 3 times, in 3 gender specific sites. There were 7 expert observers and 8 novices. We used a Hosand BX 2000 Ultrasonic Adipometer to measure USATT.

91% of the measurement's deviations from the mean were between -4 and 4 mm. Variance of deviation from mean measurements for novices was 5.93 mm, while for experts it was 5.40 mm. Standard error of measurement (SEM) and intraclass correlation coefficient (ICC) for calculated body fat percentage (BF%) (intra-observer SEM=0.78, ICC=0.98; inter-observer SEM=0.45, ICC=0.99) and for all the USATT measurements (intra-observer SEM=0.54, ICC=0.98; inter-observer SEM=0.75, ICC=0.96), showed excellent reliability. The expert observers showed slightly higher ICC and lower SEM values compared to novices.

The intra and inter-observer reliability of the adipometer was very good in measuring the USATT. There was no notable difference between expert and novice observers, thus suggesting that the method can be reliably used by anyone after a brief training, for both research and clinical practice.