The relationship between Autism Spectrum Quotient (AQ) and uneven intellectual development in school-age children

Figures & data

Table 1. Characteristics of sample by referral category means

Referral category (n)	Number of girls in category	Age in years (SD)	AQ (autistic-like traits) (SD)	IQ (BAS) (SD)	Verbal score (VIQ) (SD)	Non-verbal reasoning score (NIQ) (SD)	Spatial ability score (SIQ) (SD)
ASD referrals (31)	4	12.5 (2.0)	93.5 (17.5)	92.0 (15.4)	92.4 (19.5)	94.4 (18.2)	93.2 (22.2)
Behaviour referrals (27)	6	10.4 (1.9)	66.9 (20.4)	97.9 (19.5)	97.3 (21.8)	103.1 (13.7)	94.4 (20.2)
Academic progress referrals (48)	16	10.4 (2.8)	55.7 (18.7)	99.1 (22.3)	101.3 (21.1)	99.1 (18.9)	97.3 (22.4)
Full sample (N = 106)	26	11.0 (2.6)	69.6 (24.6)	96.7 (19.8)	97.7 (21.0)	98.8 (17.6)	95.4 (21.7)

Table 2. Brief description of the six core scales of the BAS-II items by cognitive domain

Cognitive domain	Core scale	Task
Verbal	Word Definitions	Define given words to show accurate understanding
	Verbal Similarities	Identify how three given words are related in meaning
Non-verbal Reasoning	Matrices	Choose a design that completes a matrix of related designs
	Quantitative Reasoning	Identify sequential relations between shapes/numbers
Spatial	Pattern Construction	Arrange two-tone plastic cubes to copy 2-dimensional patterns. (Directly equivalent to the Block Design sub-test of Wechsler IQ batteries)
	Recall of Designs	Draw copies of geometric designs using short-term visual memory

Figure 1. Mean intellectual unevenness scores of children at three different AQ levels: firstly, children with AQ below the average for the general population (boys: 46; girls: 38); secondly, children with AQ above the average for the general population; and thirdly, children with AQ scores in the clinical range (AQ > 75). Error bars represent 95% confidence intervals.

Figure 2. Mean composite intellectual unevenness score of children at three different AQ levels: firstly, children with AQ below the average for the general population (boys: 46; girls: 38); secondly, children with AQ above the average for the general population; and thirdly, children with AQ scores in the clinical range (AQ > 75). Error bars represent 95% confidence intervals.

Table 3. Standard multiple regression analysis of seven variables on Autism Spectrum Quotient (n = 106)

Variable	Unstandardised coefficients (standard error)	Standardised coefficients (Beta)	Variance proportion (unique)	Significance (ns: p > .05)
Total scale discrepancy	0.49 (0.16)	0.27	0.061	p = 0.003
Largest cluster discrepancy	0.45 (.16)	0.26	0.052	p = 0.006
Dyslexic-type discrepancy	0.29 (0.11)	0.26	0.047	p = 0.009
Hyperlexic-type discrepancy	0.43 (0.12)	0.35	0.085	p < 0.0005
NIQ	− 0.40 (0.15)	− 0.29	0.045	p = 0.010
VIQ	0.08 (0.13)	0.07	0.003	p = 0.531 (ns)
SIQ	0.10 (0.13)	0.09	0.004	p = 0.453 (ns)

Model overall: R = 0.60 (p < .0005); R⁽²⁾ = 0.36.

Table 4. Correlations (R) between the standard multiple regression model and AQ for each of seven specific categories of participant

Category of participant	ASD referral	Behaviour referral	Academic progress referral	Girls	Boys	Lowest ages Mean: 9.0 years (SD 1.2)	Highest ages Mean: 13.1 years (SD 1.8)
n	31	27	48	26	80	53	53
Model correlation with AQ (R)	0.51	0.54	0.52	0.82	0.62	0.60	0.54

Table 5. Mean BAS cognitive ability standardised scores (AQ > 75; n = 38)

Scale/Cluster	Mean standard score (n = 38)	t (df 37)	Significance (2 tailed; p < 0.05)
Verbal Similarities; Word Definitions	48.47; 45.47
Difference	3.00	2.006	p = 0.052^*
Matrices; Quantitative Reasoning	50.53; 45.79
Difference	4.74	2.940	p = 0.006
Pattern Construction; Recall of Designs	50.55; 45.05
Difference	5.50	2.615	p = 0.013
NIQ cluster; SIQ cluster	96.63; 95.66
Difference	0.97	0.275	Not significant
NIQ cluster; VIQ cluster	96.63; 95.16
Difference	1.47	0.385	Not significant
SIQ cluster; VIQ cluster	95.66; 95.16
Difference	0.50	0.117	Not significant

^* Borderline significance (0.05 level).