Discriminatory Performance of the Calcaneal Quantitative Ultrasound and Osteoporosis Self-Assessment Tool to Select Older Women for Dual-Energy X-ray Absorptiometry.

The objective of this cross-sectional study was to evaluate the accuracy of the calcaneal quantitative ultrasound (QUS) and the Osteoporosis Self-Assessment Tool (OST) in identifying older women with osteoporosis as defined by dual-energy X-ray absorptiometry (DXA), and to establish optimal cutoffs to determine risk. We assessed bone mineral density of the femoral neck and lumbar spine using DXA and subsequent calcaneal QUS and OST measurements in 174 women aged 50-80 years. Pearson product correlation coefficients between QUS, OST, and DXA parameters were calculated. Receiver operating characteristic curves were constructed and areas under the curves (AUCs) and optimal thresholds for QUS and OST were defined based on sensitivity, specificity, and likelihood ratio analysis. The ability of calcaneal QUS to identify women with a T-score ≤-2.5 at the femoral neck (AUC = 0.892) consistently outperformed a T-score ≤-2.5 at the lumbar spine (AUC = 0.696) and OST at both the femoral neck and lumbar spine (AUC = 0.706-0.807). Stiffness index cutoff values that fall between 65 and 78 were found to warrant DXA screening, with a cutoff <65 indicating high likelihood of osteoporosis. Further prospective research is needed to examine the gender-related differences of QUS and OST diagnostic performance and their usefulness in clinical practice.