The BOD POD has been consistently validated as a legitimate device for measuring body fat. Previous research conducted with a portable ultrasound machine and DEXA and found a strong correlation between the two methods in males (r=0.98, p<0.01) and females (r=0.99, p<0.01). The purpose of this study was to compare the accuracy of the BodyMetrix Ultrasound wand with the Bod Pod. Our hypothesis, based on our pilot study, was that the Wand would highly correlate with the BOD POD in determining body fat percentage.
Method:
An initial pilot study was conducted with 30 subjects (15 men, 15 women). The 3 site Jackson-Pollack equation was used for wand calculations. The results showed a correlation of r = 0.887, p = 0.001). The second phase of the study included 40 subjects (18 men, 22 women), between the ages of 18 and 57. Prior to testing, subjects were instructed to follow the instructions and clothing requirements for testing in the Bod Pod. The 7 site Jackson-Pollack equation was used to calculate bodyfat using the wand. Each subject participated in both the BOD POD and the BodyMetrix Ultrasound Wand exams.
Analysis/Results:
SPSS version 20 was used to analyze the data using a Pearson’s r correlation. There was a significant correlation between the accuracy of the Wand when compared to the BOD POD (r(38) = 0.910, p = 0.01). The overall mean bodyfat using the BOD POD was 19.938(s = 8.940) and the mean of the BodyMetrix Ultrasound Wand was 18.123 (s = 7.571). The mean for the males with the BOD POD was 12.994 (s = 5.487) and 11.433(s = 4.02) for the Wand. The mean for females with the BOD POD was 25.618(s = 6.996) and 23.595 (s = 4.861) for the Wand. In comparison to our pilot study, the 7 site proved to have a higher correlation coefficient (0.91 vs 0 .887).
Conclusions:
The results showed that the ultrasound wand was accurate when compared to the BOD POD. The BodyMetrix Ultrasound Wand should be considered a reliable alternative due to its accuracy, portability and cost effectiveness. Our recommendations for further study are: to have a larger sample size, broader range of subjects (including age and weight), and a third form of testing, such as hydrostatic weighing.