Table 4.

Results of ROC analysis

	AUC (95%CI)	P value	Cutoff	Sensitivity	Specificity
Average of the lowest T-score	0.791 (0.674-0.909)	< 0.001	−2.55	87.5%	65%
Average HU value
L1	0.907 (0.840-0.975)	< 0.001	124.6	93.8%	78.3%
L1-L4 horizontal plane	0.909 (0.834-0.984)	< 0.001	115.7	93.8%	81.7%
L1-L4 sagittal plane	0.891 (0.809-0.973)	< 0.001	114.9	87.5%	81.7%
Operated segment	0.880 (0.789-0.970)	< 0.001	116.1	93.8%	80.0%
Upper vertebrae of operated segment	0.885 (0.785-0.986)	< 0.001	111.8	93.8%	81.7%
Lower vertebrae of operated segment	0.866 (0.782-0.949)	< 0.001	121.0	93.8%	73.3%

Abbreviations: ROC Receiver operating characteristic curve