Abstract
The rise in global obesity rates over the past 30 years is one of the most serious crises in the world today. Obesity is associated with many serious health risks, and the cost of medical treatment for obesity is estimated at approximately $150,000,000,000 annually. Medical professionals need to find methods to not only treat and to help prevent obesity, but quickly and accurately assess it as well. With dozens of body fat assessment tools of varying reliability and validity, it is important to investigate all potential measures for use in combating the obesity epidemic. PURPOSE: The purpose of this study is to assess the Intra-rater reliability of diagnostic ultrasound in the measurement of subcutaneous adipose tissue. Previous research has concluded that diagnostic ultrasound is a valid tool for measurement of total body fat percentage, but research on the Intra-rater reliability of the tool is limited at this time. METHODS: 75 participants were recruited to participate in this study. Participants had their body fat assessed in a Bod Pod prior to ultrasound measurements to further expand the data analysis. Additionally, age, gender, and ethnicity were collected to better assess factors that might influence reliability. Participants then had two sites measured for adipose tissue size based on a previous study (Leahy et al., 2012). Each site was measured three separate times to evaluate intra-rater reliability of the diagnostic ultrasound. The collected data were analyzed with intra-class correlation for intra-rater reliability. RESULTS: The ICC for diagnostic ultrasound in the measurement of subcutaneous adipose tissue was found to be .999 for the total sample at all three tested sites. Intra-rater reliability can vary between 0 and 1.0, where 0 represents no reliability, and 1.0 represents perfect reliability (Weir, 2005). Additionally, ICC was found to be greater than or equal to .993 at all age groups above 18 at all three tested sites, and above .996 at all body fat percentages from less than 10% to greater than 30% at all three tested sites. Finally, ICC was found to be above .967 at all three tested sites in all ethnicities evaluated, including Asian, Caucasian, Hispanic, and African-American. Overall, the intra-rater reliability of diagnostic ultrasound in the measure of subcutaneous adipose tissue was found to be strong in all genders, ethnicities, ages, and body composition types measured. CONCLUSION: Diagnostic ultrasound demonstrated excellent intra-rater reliability in the measurement of subcutaneous adipose tissue. Given the previously demonstrated validity of diagnostic ultrasound in the measurement of total body fat percentage (Leahy et al., 2012), this research further supports diagnostic ultrasound as an effective tool for accurately measuring total body fat percentage.