Table 2.

Summary of Repetitive and Stereotyped Movement Scales(RSMS)

								ANCOVA	pairwise group differences
									ASD and LR	ASD and HR- neg	LR and HR- neg
Characteristic		HR-ASD (n = 30)		HR-neg (n = 75		LR (n = 53)		F(2,154)	da	da	da
		m	sd	m	sd	m	sd
RSM Composite		4.93	2.90	3.58	2.73	2.38	1.76	6.94***	1.15***	0.49*	0.51*
RSM with Body
Rate		3.17	3.72	1.76	2.68	0.98	1.95	4.70**	0.82**	0.47*	0.33
Inventory		1.07	1.05	0.73	0.79	0.47	0.64	4.80**	0.75**	0.39	0.36
Flaps [count( %)]b		20/30(66.7)		34/75(45.3)		15/53(28.3)
Rubs Body		5/30(16.7)		7/75(9.3)		5/53(9.4)
Pats Body		5/30(16.7)		7/75(9.3)		2/53(3.8)
Stiffens		2/30(6.7)		6/75(8.0)		3/53(5.7)
Body Cluster		2.13	2.12	1.31	1.59	0.80	1.18	5.61**	0.85***	0.47*	0.36
RSM with Objects
Rate		3.57	2.99	2.60	2.49	1.70	1.60	3.49*	0.86*	0.37	0.42
Total Inventory		1.63	1.22	1.40	1.01	1.04	0.85	1.83
Restricted		1.30	1.02	1.01	1.02	0.77	0.75	1.47
Swipes		6/30(20%)		17/75(22.7%)		9/53(17.0%)
Rubs/Squeeze		14/30(46.7%)		24/75(32.0%)		22/53(41.5%)
Rocks/Flips		11/30(36.7%)		14/75(18.7%)		6/53(11.3%)
Spins/Wobbles		1/30(3.3%)		5/75(6.7%)		1/53(1.9%)
Rolls		9/30(30.0%)		16/75(21.3%)		3/53(5.7%)
Sameness		0.27	0.52	0.37	0.61	0.26	0.45	0.89
Lines up/Stack		0/30		3/75(4.0%)		1/53(1.9%)
Collects		5/30(16.7%)		13/75(17.3%)		11/53(20.8%)
Moves/Places		3/30(10%)		12/75(16.0%)		2/53(3.8%)
Clutches		0/30		0/75		0/53
Object Cluster		2.80	1.96	2.28	1.74	1.58	1.32	3.14*	0.78*	0.29	0.45*

Note: ANCOVA = analysis of covariance; ASD = autism spectrum disorder; HR = high-risk; LR = low-risk; neg = negative; RSM = repetitive and stereotyped movement.

^aEffect size based on Cohen’s d, using pooled variance as the denominator.

^bCounts and percentages represent the number of children who showed this behavior per each group.

^*p ≤ .05,

^**p ≤ .01,

^***p ≤ .001