Table 2.

The area under the ROC curve by binary logistic regression analysis (2 classes classification)

Clinical scenario		A + versus A- (stage 1–6)		A + versus A- (stage 1–3)		Stage 1–3 vs. 4–6 in A+
Cases number		n = 371		n = 258		n = 143
Variable	Model	AUC	accuracy	AUC	accuracy	AUC	accuracy
Combined-panel	a	0.949	0.895	0.949	0.911	0.608	0.594
Combined-panel (by 5 PCA)	a	0.938	0.871	0.948	0.891	0.596	0.573
pTau217	a	0.944	0.865	0.947	0.876	0.651	0.566
pTau181	a	0.859	0.784	0.855	0.771	0.580	0.573
GFAP	a	0.834	0.771	0.821	0.802	0.605	0.559
pTau217 & pTau181	a	0.941	0.860	0.931	0.891	0.637	0.566
pTau217 & pTau181 (PCA)	a	0.912	0.825	0.914	0.837	0.625	0.566
pTau217 & GFAP	a	0.939	0.863	0.944	0.872	0.642	0.601
pTau217 & GFAP (PCA)	a	0.914	0.860	0.923	0.872	0.644	0.601
pTau181 & GFAP	a	0.866	0.817	0.860	0.837	0.591	0.559
pTau181 & GFAP (PCA)	a	0.873	0.827	0.868	0.829	0.607	0.566
Combined-panel	b	0.946	0.889	0.945	0.911	0.567	0.566
Combined-panel (by 6 PCA)	b	0.932	0.871	0.935	0.888	0.575	0.545
pTau217	b	0.942	0.871	0.942	0.864	0.604	0.552
pTau181	b	0.855	0.782	0.839	0.779	0.536	0.566
GFAP	b	0.825	0.760	0.806	0.795	0.549	0.539
pTau217 & pTau181	b	0.939	0.879	0.927	0.876	0.594	0.573
pTau217 & pTau181 (PCA)	b	0.910	0.822	0.893	0.829	0.605	0.559
pTau217 & GFAP	b	0.937	0.871	0.939	0.868	0.605	0.580
pTau217 & GFAP (PCA)	b	0.897	0.852	0.895	0.872	0.631	0.587
pTau181 & GFAP	b	0.861	0.819	0.849	0.833	0.550	0.524
pTau181 & GFAP (PCA)	b	0.844	0.811	0.825	0.810	0.593	0.566

Accuracy is computed by the cut probability = 0.5

2 classes indicated amyloid positive (A+) or negative (A-) status

ROC: receiver operating characteristic, AUC: area under the ROC curve, PCA: Principal component analysis, GFAP, glial fibrillary acidic protein; NFL, neurofilament light chain

Model a includes only the listed test variable

Model b includes test variable and age, gender, educational years

A + versus A- (stage 1–6):

Combined-panel equation = 6.318pTau217) + 0.022pTau181)-54.52 (Aβ42/40)-0.072NFL) + 0.003GFAP) -0.267 (Total tau). Combined-panel (by PCA5 or PCA6) (scores computed on the first 5 or 6 principal components)

(I) By PCA_Combined-panel equation = 1.747(pTau217) + 1.610pTau181) − 0.652(Aβ42/40) – 3.071NFL) + 0.942GFAP) − 0.617(Total tau)

(II) By PCA_Combined-panel equation = − 0.875PC1–2.676PC2 + 2.364PC3 + 1.804PC4–0.039PC5

A + versus A- (stage 1–3):

Combined-panel equation = 12.071pTau217)-0.042pTau181)-57.85 (Aβ42/40)-0.065NFL) + 0.003GFAP) -0.038 (Total tau)

(I) By PCA Combined-panel equation = 1.95pTau217) − 1.459pTau181) − 0.579(Aβ42/40) – 3.903NFL) + 0.758GFAP) − 0.036(Total tau)

(II) By PCA Combined-panel equation = 0.573PC1–2.915PC2–2.283PC3 + 0.414PC4 + 2.806PC5

Stage 1–3 vs. 4–6 in A+:

Combined-panel equation = 1.51pTau217)-0.019pTau181) + 26.322 (Aβ42/40) + 0.006NFL) + 0.001GFAP) + 0.004 (Total tau)

(I) By PCA Combined-panel equation = 0.202pTau217) − 0.175pTau181) + 0.173(Aβ42/40) + 0.123NFL) + 0.371GFAP) + 0.0004(Total tau)

(II) By PCA Combined-panel equation = − 0.375PC1 + 0.24PC2 + 0.175PC3–0.045PC4 + 0.152PC5