Table 2. Cutoff value for the prediction of severe Graves' orbitopathy course of the third-generation TBII and Mc4-TSI bioassay using Youden method.

	TBII assay≥10.67 IL/l	TSI bioassay≥555.10%
	% (95% CI)	% (95% CI)
Sensitivity	66.7 (51.9–81.5)	69.2 (54.7–83.7)
Specificity	84.9 (76.7–93.1)	89.0 (81.9–96.2)
AUC	0.817 (0.732–0.902)	0.868 (0.803–0.934)

Abbreviations: AUC, area under the curve; CI, confidence interval; TBII, thyrotropin-binding inhibitory immunoglobulin; TSI, thyroid-stimulating immunoglobulin.