Interdevice Reliability of A-Mode Ultrasound to Measure Body Composition

A-mode ultrasound is a noninvasive, rapid method for measuring subcutaneous fat thickness and estimating body fat percentage (%BF). Validity and reliability of the BodyMetrix BX2000 A-mode ultrasound has been reported; however, this study aimed to compare results from two machines to determine interdevice reliability. Ultrasound measures were repeated with two BX2000 machines at 10 body sites (chest, biceps, triceps, scapula, lower back, hip, waist, thigh, calf, axilla) on 42 males of varying age and leanness (age: 28.6±11.9 y, BMI: 25.4±4.6 kg/m2). The intraclass correlation coefficients ranged from 0.939 to 0.998 with standard errors of measurement from 0.31 to 0.58 mm of fat thickness. The largest mean difference between devices was 0.37 mm at the scapula. The difference between machines in %BF was not significant (0.34%BF; p=0.09). The interdevice reliability is similar to the previously reported test-retest reliability with no clinical significance between machines