Table 4.

Group Differences in Proportion of Acts with a Vocalization, Eye Gaze, and Coordinated with Vocalization, Gaze, and Gesture

								Pairwise group differences
	ASD (n = 50)		DD (n = 25)		TD (n = 50)			DD-ASD		TD-ASD
Measure	M	SD	M	SD	M	SD	F value	p value	Effect sized	p value	Effect sized
Acts with Vocalization (%)
Total Acts	54.46a	27.01	59.36a	31.40	76.74b	18.96	12.39***	.879	0.17	.000	0.97
Behavior Regulation	47.30a	31.03	52.34ab	34.94	67.62b	24.90	6.92**	.903	0.15	.001	0.73
Social Interaction	50.14a	36.36	59.96a	36.70	64.74a	31.23	1.94	.679	0.27	.149	0.43
Joint Attention	85.08a	27.47	72.63a	31.77	87.64a	16.97	2.16	.350	−0.42	.945	0.12
Acts with Gaze (%)
Total Acts	42.26a	27.30	49.87a	16.93	51.96a	17.16	2.25	.368	0.34	.105	0.44
Behavior Regulation	22.39a	26.53	27.47a	29.88	30.61a	30.70	1.02	.853	0.18	.395	0.29
Social Interaction	54.79a	46.69	73.69a	31.31	63.25a	31.16	1.80	.180	0.48	.707	0.22
Joint Attention	60.60a	38.65	51.86a	30.07	53.18a	20.42	0.61	.709	−0.25	.650	−0.25
Acts Coordinated with Vocalization, Gaze, and Gesture (%)
Total Acts	17.17a	14.69	20.62a	15.84	22.94a	10.88	2.47	.742	0.23	.081	0.45
Behavior Regulation	14.80a	13.05	20.93ab	22.93	24.16b	15.29	5.45	.525	0.34	.004	0.66
Social Interaction	23.79a	25.77	27.86a	29.29	23.19a	23.98	0.26	.929	0.15	.999	−0.02
Joint Attention	13.52a	20.29	18.62a	18.20	20.83a	12.52	1.82	.690	0.27	.170	0.45

Note: Means in the same row with different subscripts differ significantly at p <.05.

Proportion is the total number of coordinated acts for each function divided by the total number of acts for that function.

Degrees of freedom are Welch corrected when necessary forviolation of homogeneity of variance as assessed by Levene’s test.

^dEffect size based on Cohen’s d = .20 is small, .50 is medium, and .80 is large

^*p <.05

^**p <.01

^***p <.001