. 2021 Sep 13;13:33. doi: 10.1186/s11689-021-09390-1

Table 2.

Percent differences in EEG power associated with effects of ASD, sex, and age for the 5 frequency bands and by 9 regions of interest along the anterior to posterior gradient (anterior, central, and posterior) and hemisphere (left, midline [mid], and right).

		Delta			Theta			Alpha			Beta			Gamma
		Left	Mid	Right	Left	Mid	Right	Left	Mid	Right	Left	Mid	Right	Left	Mid	Right
ASD
Anterior	% Diff	− 4%	− 4%	− 4%	6%	6%	3%	26%	20%	22%	− 2%	− 2%	− 6%	− 5%	− 8%	− 12%
Anterior	p-val	0.405	0.393	0.371	0.306	0.385	0.663	0.001	0.011	0.004	0.775	0.724	0.442	0.604	0.181	0.184
Center	% Diff	− 4%	0%	3%	8%	11%	14%	36%	38%	46%	2%	3%	5%	(int.²)	− 9%	− 15%
Center	p-val	0.449	0.955	0.583	0.298	0.168	0.059	0.001	0.001	< 0.001	0.793	0.629	0.489	(int.²)	0.110	0.077
Posterior	% Diff	− 5%	2%	2%	3%	9%	12%	23%	25%	35%	0%	3%	7%	− 16%	− 10%	− 13%
Posterior	p-val	0.416	0.738	0.790	0.676	0.248	0.141	0.039	0.039	0.002	0.946	0.669	0.371	0.031	0.230	0.094
Male sex
Anterior	% Diff	23%	15%	26%	17%	7%	19%	15%	4%	15%	(int.¹)	3%	23%	(int.³)	− 14%	10%
Anterior	p-val	0.001	0.004	< 0.001	< 0.001	0.280	0.001	0.034	0.548	0.025	(int.¹)	0.598	0.007	(int.³)	0.018	0.332
Center	% Diff	44%	46%	43%	40%	50%	42%	39%	41%	57%	36%	35%	42%	(int.²)	10%	42%
Center	p-val	< 0.001	< 0.001	< 0.001	< 0.001	< 0.001	< 0.001	< 0.001	< 0.001	< 0.001	< 0.001	< 0.001	< 0.001	(int.²)	0.073	< 0.001
Posterior	% Diff	46%	34%	42%	48%	36%	48%	58%	50%	61%	41%	39%	41%	44%	45%	41%
Posterior	p-val	< 0.001	< 0.001	< 0.001	< 0.001	0.002	< 0.001	< 0.001	0.001	< 0.001	< 0.001	< 0.001	< 0.001	< 0.001	< 0.001	< 0.001
Age (years)
Anterior	% Diff	− 11%	− 13%	− 12%	− 12%	− 13%	− 13%	− 8%	− 8%	− 10%	(int.¹)	− 7%	− 10%	(int.³)	− 6%	− 7%
Anterior	p-val	< 0.001	< 0.001	< 0.001	< 0.001	< 0.001	< 0.001	< 0.001	< 0.001	< 0.001	(int.¹)	< 0.001	< 0.001	(int.³)	< 0.001	< 0.001
Center	% Diff	− 16%	− 12%	− 14%	− 16%	− 13%	− 16%	− 11%	− 8%	− 11%	− 8%	− 5%	− 8%	− 5%	− 1%	− 4%
Center	p-val	< 0.001	< 0.001	< 0.001	< 0.001	< 0.001	< 0.001	< 0.001	< 0.001	< 0.001	< 0.001	< 0.001	< 0.001	0.003	.107	0.031
Posterior	% Diff	− 16%	− 14%	− 16%	− 16%	− 14%	− 16%	− 10%	− 10%	− 10%	− 8%	− 5%	− 8%	− 4%	− 1%	− 4%
Posterior	p-val	< 0.001	< 0.001	< 0.001	< 0.001	< 0.001	< 0.001	< 0.001	< 0.001	< 0.001	< 0.001	< 0.001	< 0.001	0.002	0.527	0.014

A separate linear mixed-effects model was run for each frequency-region combination. Models included ASD, age, and sex as covariates, and accounted for clustering by site and family. Participants ranged in age from 8 to 17 years

Interpretation for each estimate is as follows:

ASD: The percent difference in power associated with NO autism diagnosis, compared to children WITH an autism diagnosis, adjusting for ASD and sex

Sex: The percent difference in power associated with being male, compared to being female, adjusting for ASD and sex

Age: The percent difference in power associated with a 1-year increase in age, adjusting for ASD and sex

Int.1, int.2, int.3: interaction observed thus stratum specific estimates provided as follows:

1: For males, percent difference is − 10.8% for each additional year of age, vs −6.0% for females (both p < 0.001)

2: For males, percent difference is 4.2% for no ASD compared to ASD (not significant), vs − 28.0% for females (p = 0.015)

3: For males, percent difference is − 10.8% for each additional year of age (p < 0.001), vs − 2.4% for females (not significant)

Models which had significant interaction terms are thus indicated; otherwise interaction terms were not significant and therefore not included in the model