Table 2.

Sensitivity, specificity, positive and negative predictive values, and regression statistics of week 2 diagnoses to predict week 9 traumatic stress diagnoses

		Regression Statistics
Week 2 Predictor	Week 9 Outcome	χ2	P	Odds Ratio	Positive Predictive Value	Negative Predictive Value	Sensitivity	Specificity	Percentage Correctly Identified
DSM‐5
ASD	PTSD	28.95	<.0001	26.91	0.48	0.97	0.70	0.92	89.9
4+ symptoms	PTSD	28.95	<.0001	15.79	0.30	0.97	0.80	0.80	79.8
“Two‐week PTSD”a	PTSD	36.55	<.0001	22.64	0.41	0.97	0.75	0.88	87.0
Preschool PTSD	Preschool PTSD	39.08	<.0001	26.08	0.39	0.98	0.80	0.87	86.1
DSM‐IV
ASD (DSM‐IV)	PTSD (DSM‐IV)	34.58	<.0001	24.21	0.37	0.98	0.78	0.87	86.5
Either algorithm
ASD	PTSD	35.59	<.0001	21.52	0.39	0.97	0.75	0.88	86.5

Note. Sensitivity = Likelihood that someone with a given diagnosis at week 9 would have met criteria for the relevant diagnosis at week 2. Specificity = Likelihood that someone without a given diagnosis at week 9 would also not have met criteria for the relevant diagnosis at week 2. Positive predictive value = Likelihood that someone with a given diagnosis at week 2 would have the relevant diagnosis at week 9. Negative predictive value = Likelihood that someone without a given diagnosis at week 2 would not have the relevant diagnosis at week 9.

^a“Two‐week PTSD” this refers to an “early PTSD” algorithm, that is, ignores the requirement that symptoms be present for at least 4 weeks.