Fig. 1.

(A–C) Receiver operating characteristic curves of the S1P concentration, FRAX probability, and TBS alone and in combination for predicting osteoporotic fracture. FRAX model: the highest FRAX probability tertile (≥5.18%). S1P model: the highest S1P concentration tertile (≥3.30 μmol/L). TBS model: the lowest TBS tertile (<1.386). AUC, area under the receiver operating characteristic curve; S1P, sphingosine 1-phosphate; FRAX, fracture risk assessment tool; CI, confidence interval; TBS, trabecular bone score; Ref, reference.