Table 5. Means (SD) and bootstrapped ANCOVA comparisons between no-SI and SI groups on key variables controlling for age and depression.

	No-SI (n = 1241)		SI (n = 610)		F-statistic
Variablea	M	SD	M	SD	df = 1, 1847	p-valueb	BCa 95% CIc	Cohen’s d [95% CI]
Social communication difficulties	9.36	2.60	11.17	2.20	128.82	< .001	-1.99, -1.39	-0.73 [-0.88, -0.56]
Insistence on sameness	41.16	13.61	50.70	12.80	17.51	< .001	-4.66, -1.68	-0.72 [-1.47, 0.30]
Attentional control	24.51	6.30	18.79	5.45	36.53	< .001	1.34, 2.67	0.95 [0.60, 1.38]
Inhibitory control	31.23	6.76	28.71	4.29	7.62	.003	0.354, 1.67	0.42 [0.04, 0.76]
Rumination	8.07	4.55	11.72	4.30	1.07	.316	-0.714, 0.236	-0.82 [-1.07, -0.48]
Covariates					df = 1, 1849
Age	38.82	12.20	33.56	11.67	78.06	< .001	4.05, 6.44	0.44 [-0.24, 1.36]
Depression	1.89	1.93	4.72	1.99	864.60	< .001	-3.03, -2.63	-1.45 [-1.56, -1.29]

^aAge and depression entered as covariates in the model.

^b5000 samples bootstrapped p-value.

^cBCa 95% confidence intervals that do not cross zero are bolded.