Quantitative Ultrasound Normative Reference Data for Community-Dwelling White and Black Females in the United States

Quantitative ultrasound (QUS) race-specific normative reference data are not available for accurate calculation of Z-scores. The primary aims of this study were (1) to develop a race-specific QUS reference database for white and black females and to compare estimated fracture risk between these 2 racial groups and (2) to compare stiffness index (SI) values of white females in this study to manufacturer-obtained values. Subjects included 1111 females (31% black), aged 20-85 yr (52 ± 19 yr), with a mean SI score of 93.7 ± 20.1. White females, aged 20-39 yr (n = 213), were used to calculate T-scores, whereas Z-scores were age and race specific. Black females had significantly higher SI scores than white females (p < 0.001). White females aged 50+ yr in this study had significantly higher SI scores compared with manufacturer-derived values. Results highlight the need for population- and race-specific normative data when using QUS as a screening tool for identifying high fracture risk.