Table 2.

Classification statistics for DAWBA

DAWBA result		Sensitivity	Specificity	PPV	NPV	Correctly classified overall (%)
Computer generated probability a
Positive if using this cut‐off	‘Very low (.1%)’	1.00	.00	.41	–	40.6
	‘Low (.5%)’	.94	.79	.75	.95	84.8
	‘Low (3%)’	.88	.85	.80	.91	86.2
	‘Moderate (20%)’	.69	.91	.84	.81	81.9
	‘50/50%’	.38	.97	.89	.69	72.8
	‘High (80%)’	.20	.99	.96	.64	67.0
DAWBA clinical rater a
Positive if rating of	Any ASD	.86	.87	.82	.90	86.6
	Autism/Asperger's	.54	.98	.95	.76	80.5
DAWBA clinical rater ± ADOS b
Positive if rating of	Any ASD	.86	.80	.83	.83	83.0
	AND ADOS +ve	.74	.95	.94	.77	84.0
	OR ADOS +ve	.98	.69	.78	.97	84.4
	Autism/Asperger's	.54	.97	.95	.66	74.5
	AND ADOS +ve	.49	.99	.98	.63	72.6
	OR ADOS +ve	.92	.82	.85	.90	87.3

Classification statistics for DAWBA probability bands (upper panel), for diagnosis assigned by clinical rater (middle panel), and for diagnosis by clinical rater in combination with ADOS classification (met ASD criteria according to revised algorithm; see online supplement). PPV, positive predictive value, indicates the proportion of children at and above each cut‐off who have BERD of ASD; NPV, negative predictive value, indicates the proportion of children below each cut‐off without a BERD of ASD.

^aComparison group includes unaffected cotwins and low‐risk twins.

^bComparison group is unaffected cotwins only.