Table 8.

Best 6 Predictors of Insulin Resistance (Cutoffs ≥150 and ≥177 mg/dL) Arranged According to Their PTPRs

Predictors With Cutoffs	Cutoff	PTPR	AUROC	Sensitivity	Specificity	Positive Predictive Value	FN Rate	Youden Index	Global Accuracy
I0*G60 >1110 (>428 SI units)	≥150	7.00	0.867	0.865	0.793	0.744	0.135	0.657	0.822
	≥177	9.84	0.868	0.900	0.733	0.628	0.100	0.633	0.789
ISI composite <4.45	≥150	4.90	0.835	0.811	0.774	0.714	0.189	0.584	0.789
	≥177	7.43	0.843	0.868	0.733	0.619	0.133	0.600	0.778
AUC-Gl*In/′ >5816	≥150	4.68	0.805	0.865	0.623	0.615	0.135	0.487	0.722
	≥177	6.58	0.817	0.900	0.583	0.519	0.100	0.483	0.689
QUICKI <0.341	≥150	4.26	0.829	0.757	0.811	0.737	0.243	0.568	0.789
	≥177	5.47	0.835	0.800	0.767	0.632	0.200	0.567	0.778
HOMA1 >2.09	≥150	3.87	0.826	0.793	0.811	0.730	0.207	0.541	0.778
	≥177	5.47	0.836	0.800	0.767	0.632	0.200	0.567	0.778
HOMA2 >1.24	≥150	3.69	0.829	0.649	0.887	0.800	0.351	0.535	0.789
	≥177	4.71	0.829	0.767	0.767	0.800	0.233	0.533	0.767

The highest PTPR, the best sensitivity, the best Youden index, and the best global accuracy were exhibited by the I0*G60, along with the lowest FN rate. The second performance was that of the ISI composite, followed by AUC-Gli*In/′, QUICKI, HOMA1, and HOMA2. Had we chosen the lowest value of the third tertile of the SSPG values (≥177 mg/dL) as the diagnostic cutoff to define IR (instead of ≥150 mg/dL) the ROC-defined cutoffs of the six best predictors would have remained unchanged, and the I0*G60 would have remained the best predictor. Exempting HOMA2, their AUROCs would have experienced a slight improvement. The sensitivities of the predictors would have improved, and their FN rates would have been reduced. However, the specificities would have been reduced, and the global accuracies would have fallen slightly (with the exemption of HOMA1). These changes would have occurred at the expense of labeling 18.9% of the IR subjects as NIR subjects.