. Author manuscript; available in PMC: 2020 Apr 1.

Published in final edited form as: J Trauma Stress. 2019 Apr;32(2):226–237. doi: 10.1002/jts.22399

Table 4.

Algorithm Performance Characteristics in the Chart Reviewed Sample and in the VHA Population

	Chart reviewed sample (N = 485)						VHA population (weighted bootstrapped results)

		Se	Sp	PPV	NPV	AUC	Se [95% CI]	Sp [95% CI]	PPV^a [95% CI]	NPV^a [95% CI]

	Drop Poss.^b	.99	.96	.83	1.00	.98	.96 [.89, 1.0]	1.0 [.99, 1.0]	.96 [.90, 1.0]	1.0 [.99, 1.0]
ICD Alg.	Poss.+ Case	.97	.76	.47	.99	.93	.75 [.66, .94]	.98 [.96, .99]	.88 [.80, .95]	.94 [.92, .96]
	Poss.+ Cont.	.84	.87	.59	.96	.90	.86 [.75, .95]	.97 [.96, .99]	.82 [.73, .91]	.98 [.97, .99]

	Drop Poss.^c	.96	.97	.86	.99	.99	.96 [.90, 1.0]	1.0 [.99, 1.0]	.98 [.92, 1.0]	.99 [.98, 1.0]
Lasso Alg.	Poss.+ Case	.83	.96	.81	.96	.95	.65 [.56, .74]	1.0 [.99, 1.0]	.97 [.92, 1.0]	.91 [.88, .94]
	Poss.+ Cont.	.95	.84	.57	.99	.95	.95 [.89, 1.0]	.95 [.93, .97]	.72 [.61, .83]	.99 [.99, 1.0]

Note. The 3-level outcome was dichotomized to calculate performance metrics using three approaches: drop all possible PTSD, group possible PTSD with likely PTSD, and group possible PTSD with likely not PTSD. VHA = Veterans Health Administration; Se = sensitivity; Sp = specificity; PPV = positive predictive value; NPV = negative predictive value; AUC = area under the curve; CI = confidence interval; Alg. = Algorithm; Poss. = possible PTSD; Case = likely PTSD (case); Cont. = likely not PTSD (control).

PPV and NPV calculated using prevalence estimate of 18% based on random sample of chart reviews (n = 100).

n = 328.

n = 397.