Table 2.

Item domain correlations and Interrater reliability by modules

	Rater 1			Rater 2			Interrater		Correlation with Diagnosis
	M	SD	rit	M	SD	rit	Kappaa	Agreement	rpb
Module 2
SA
Pointing	0.19	0.54	0.849	0.19	0.54	0.846	1.000	100.0	0.942
Descriptive, conventional, instrumental, or informational gestures	0.13	0.34	0.576	0.19	0.40	0.465	0.765	93.7	0.381
Unusual eye contact	0.38	0.81	0.692	0.38	0.81	0.609	1.000	100.0	0.787
Facial expressions directed to others	0.38	0.62	0.81	0.50	0.63	0.737	0.789	87.5	0.689
Shared enjoyment in interaction	0.5	0.63	0.797	0.44	0.63	0.844	0.896	93.7	0.651
Showing	0.44	0.81	0.775	0.50	0.82	0.763	0.736	81.2	0.762
Spontaneous initiation of joint attention	0.13	0.34	0.846	0.25	0.45	0.455	0.600	87.5	0.882
Quality of social overtures	0.38	0.50	0.604	0.56	0.63	0.426	0.444	75.1	0.447
Amount of reciprocal social communication	0.75	0.58	0.717	0.94	0.44	0.654	0.607	81.2	0.541
Overall quality of rapport	0.56	0.73	.924	0.50	0.73	0.876	0.733	81.2	0.826
Cronbachs alpha	0.932			0.903
RRB
Stereotyped/idiosyncratic use of words or phrases	0.38	0.62	0.688	0.31	0.6	0.581	0.881	93.7	0.755
Unusual sensory interest in play material/person	0.13	0.34	− 0.182	0.19	0.4	− 0.044	0.765	93.7	− 0.173
Hand and finger and other complex mannerisms	0.19	0.54	0.902	0.25	0.58	0.923	0.837	93.7	0.915
Unusually repetitive interests or stereotyped behaviors	0.19	0.54	0.902	0.25	0.58	0.923	0.837	93.7	0.915
Cronbachs alpha	0.755			0.77
Module 3
SA
Reporting of events	0.56	0.67	0.513	0.56	0.62	0.636	0.515	68.7	0.622
Conversation	0.81	0.59	0.721	0.63	0.55	0.647	0.568	81.3	0.574
Descriptive, conventional, instrumental, or informational gestures	0	0	0	0.03	0.18	0.394	0.000	96.9	0.475
Unusual eye contact	0.25	0.67	0.620	0.25	0.67	0.576	1.000	100.0	0.714
Facial expressions directed to examiner	0.25	0.44	0.729	0.25	0.44	0.733	1.000	100.0	0.655
Shared enjoyment in interaction	0.25	0.44	0.797	0.25	0.51	0.777	0.840	93.8	0.734
Quality of social overtures	0.38	0.66	0.593	0.5	0.57	0.505	0.587	74.9	0.553
Quality of social response	0.38	0.49	0.605	0.53	0.57	0.615	0.353	65.6	0.578
Amount of reciprocal social communication	0.59	0.71	0.826	0.59	0.67	0.794	0.820	90.6	0.680
Overall quality of rapport	0.25	0.44	0.797	0.25	0.51	0.716	0.840	93.8	0.734
Cronbachs alpha	0.888			0.89
RRB
Stereotyped/idiosyncratic use of words or phrases	0.06	0.25	0.510	0.19	0.47	0.507	0.458	90.6	0.772
Unusual sensory interest in play material/person	0.06	0.35	0.588	0.06	0.35	0.339	1.000	100.0	0.475
Hand and finger and other complex mannerisms	0	0	0	0	0	0	–	100.0	–
Excessive interest in or references to unusual or highly specific topics or objects or repetitive behaviors	0.16	0.45	0.309	0.25	0.51	0.472	0.732	90.6	0.567
Cronbachs alpha	0.554			0.552

r_it item-domain correlation, r_pb point-biserial correlation

^aWeighted Kappa