Table 4.

Diagnostic Classification Accuracy and Predicted Probabilities

Percentile cutpoint	Number of tests	Sens	Spec	PPV	NPV	LR+	Posttest probability [95%CI]
Dementia classification at follow up among initially cognitively normal or MCI participants
≤16	1+	1.00	.22	.07	1.00	1.28	.07 [.04, .09]
	2+	1.00	.39	.08	1.00	1.64	.08 [.06, .11]
	3+	.94	.55	.10	.99	2.04	.10 [.07, .14]
	4+	.88	.67	.13	.99	2.66	.13 [.09, .17]
≤9	1+	.97	.38	.08	1.00	1.56	.08 [.05, .10]
	2+	.97	.57	.11	1.00	2.25	.11 [.07, .15]
	3+	.82	.73	.15	.99	3.04	.14 [.10, .19]
	4+	.71	.83	.19	.98	4.18	.19 [.13, .25]
≤5	1+	.97	.52	.10	1.00	2.02	.10 [.07, .13]
	2+	.88	.72	.15	.99	3.14	.15 [.10, .19]
	3+	.74	.84	.20	.98	4.63	.20 [.14, .27]
	4+	.62	.90	.27	.98	6.20	.25 [.17, .33]
≤2	1+	.91	.70	.14	.99	3.03	.14 [.10, .19]
	2+	.74	.83	.19	.98	4.35	.19 [.13, .25]
	3+	.53	.93	.29	.97	7.57	.29 [.19, .39]
	4+	.35	.96	.34	.96	8.75	.32 [.21, .44]
MCI classification at follow up among initially cognitively normal participants
≤16	1+	.94	.29	.14	.97	1.32	.06 [.05, .09]
	2+	.85	.51	.17	.97	1.73	.09 [.06, .12]
	3+	.66	.69	.20	.94	2.13	.11 [.07, .14]
	4+	.53	.80	.24	.93	2.65	.23 [.09, .17]
≤9	1+	.78	.47	.15	.95	1.47	.08 [.05, .10]
	2+	.70	.71	.23	.95	2.41	.12 [.08, .16]
	3+	.43	.86	.27	.93	3.07	.15 [.10, .20]
	4+	.30	.94	.36	.92	5.00	.22 [.14, .30]
≤5	1+	.77	.64	.20	.96	2.14	.11 [.07, .14]
	2+	.55	.85	.31	.94	3.67	.17 [.11, .23]
	3+	.34	.94	.39	.92	5.31	.24 [.15, .32]
	4+	.19	.97	.45	.91	6.33	.26 [.15, .37]
≤2	1+	.57	.82	.28	.94	3.17	.15 [.10, .20]
	2+	.40	.94	.44	.93	6.67	.27 [.18, .36]
	3+	.17	.98	.57	.91	8.50	.32 [.18, .47]
	4+	.09	.99	.67	.90	9.00	.33 [.13, .53]

Note. MCI = mild cognitive impairment; CI = confidence interval; Sens = sensitivity; Spec = specificity; PPV = positive predictive value; NPV = negative predictive value; LR+ = positive likelihood ratio.