Speech and language profiles in 4- to 6-year-old children with early diagnosis of autism spectrum disorder without intellectual disability

Figures & data

Table 1 VIQ and PIQ scores divided by ASD subgroup

	AD (n=20)	PDD-NOS (n=36)	AS (n=12)	AFs (n=14)	Total group (n=82)
VIQ	82.7 (14.7)	86.4 (14.1)	99.0 (13.2)	95.1 (7.0)	88.8 (14.2)
PIQ	90.8 (15.3)	98.0 (12.8)	102.0 (19.0)	101.6 (11.2)	97.4 (14.6)

Abbreviations: VIQ, verbal IQ; PIQ, performance IQ; ASD, autism spectrum disorder; AD, autistic disorder; AFs, autistic features; AS, Asperger’s syndrome; PDD-NOS, pervasive developmental disorder-not otherwise specified; IQ, Intelligence quotient.

Table 2 Specifications of measures and measure-specific impaired-range cutoffs or definitions per language factor

	Measures	Impaired-range cutoff
Receptive language	RDLS (sentence comprehension)	<Percentile 10
	SPIQ (word comprehension)	<Stanine 3
Expressive language	ITPA (word analogies)	<Stanine 3
	PT (grammar)	<Level 5 or at level 5 but <6 structures
Phonology	PSPA (phonological speech production)	Classification of “definite phonological speech problems”
	NWRT (phonological processing)	<−1.25 SD

Abbreviations: ITPA, Illinois Test of Psycholinguistic Abilities; NWRT, nonword-repetition task; PT, Processability Test; PSPA, phonological speech-production assessment; RDLS, Reynell Developmental Language Scale; SPIQ, Snabbt Performancetest på Intelligence (IQ).

Table 3 Results on the language assessments for the total group and divided by ASD subgroups

		Sentence comprehension (RDLS), median (SD) percentiles, n=83	Word comprehension (SPIQ), median (lower–upper quartile) stanines, n=83	Word analogies (ITPA), median (lower–upper quartile) stanines, n=66	Grammar (PT), distribution by processability level (%), n=81					Phonological speech production (PSPA), distribution by classification (%), n =81			Phonological processing (NWRT), median (SD) z-scores, n=78
					1	2	3	4	5	No problems	Minor problems	Definite problems
Total ASD subgroup	n=83	24.2 (29.3)	4.0 (3.0–5.0)	2.0 (1.0–4.0)	3.7	6.2	9.9	43.2	37.0	64.2	16.0	19.8	−0.9 (1.3)
	AD (n=20)	15.3 (22.9)	3.5 (2.0–4.0)	2.0 (1.0–2.75)	− (0)	10.0	10.0	55.0	25.0	47.4	31.6	21.0	−1.1 (1.1)
	PDD-NOS (n=37)	18.5 (24.3)	4.0 (3.0–5.5)	1.0 (1.0–3.0)	8.1	8.1	10.8	48.6	24.3	61.1	13.9	25.0	−1.2 (1.3)
	AS (n=12)	36.4 (36.5)	5.0 (5.0–6.0)	4.0 (3.25–5.75)	− (0)	− (0)	− (0)	18.2	81.8	91.7	8.3	− (0)	0.3 (0.8)
	AFs (n=14)	41.4 (34.7)	5.0 (3.75–6.25)	3.0 (2.0–4.0)	− (0)	− (0)	15.4	30.8	53.8	71.4	7.1	21.4	−0.9 (1.1)

Abbreviations: AD, autistic disorder; AFs, autistic features; AS, Asperger’s syndrome; ASD, autism spectrum disorder; ITPA, Illinois Test of Psycholinguistic Abilities; NWRT, nonword-repetition task; PDD-NOS, pervasive developmental disorder-not otherwise specified; PT, Processability Test; PSPA, phonological speech-production assessment; RDLS, Reynell Developmental Language Scale; SPIQ, Snabbt Performancetest på Intelligence (IQ).

Table 4 Percentage within impaired range on each language measure for the total group and divided by ASD subgroups

		Receptive language		Expressive language		Phonology
		Sentence comprehension (RDLS), n=83	Word comprehension (SPIQ), n=83	Word analogies (ITPA), n=66	Grammar (PT), n=81	Phonological speech production (ASPA), n=82	Phonological processing (NWRT), n=78
Total ASD subgroup	n=83	53	16	52	64	21	41
	AD (n=20)	60	45	75	80	21	39
	PDD-NOS (n=37)	59	11	62	76	27	53
	AS (n=12)	42	0	0	18	0	8
	AFs (n=14)	36	0	44	46	21	43

Abbreviations: AD, autistic disorder; AFs, autistic features; AS, Asperger’s syndrome; ASD, autism spectrum disorder; ITPA, Illinois Test of Psycholinguistic Abilities; NWRT, nonword-repetition task; PT, Processability Test; PSPA, phonological speech-production assessment; PDD-NOS, pervasive developmental disorder-not otherwise specified; RDLS, Reynell Developmental Language Scale; SPIQ, Snabbt Performancetest på Intelligence (IQ).

Table 5 Language profiles based on receptive language, expressive language, and phonology factors for the total group and divided by ASD subgroup

	Factors failed	Total ASD group, n=83 (%)	AD, n=20 (%)	PDD-NOS, n=37 (%)	AS, n=12 (%)	AFs, n=14 (%)
Collapsed	Expressive + receptive ± phonology	45.8	70.0	54.0	0	28.6
	Expressive ± phonology	24.1	20.0	27.0	16.7	28.6
	Receptive ± phonology	9.6	0	5.4	41.6	7.1
	Phonology only	3.6	5.0	0	0	14.3
	None	16.9	5.0	13.5	41.7	21.4
Detailed	Receptive + expressive + phonology	28.9	35.0	37.8	0	21.4
	Receptive + expressive	16.9	35.0	16.2	0	7.1
	Expressive + phonology	7.2	0	13.5	0	7.1
	Receptive + phonology	2.4	0	2.7	8.3	0
	Expressive only	16.9	20.0	13.5	16.7	21.4
	Receptive only	7.2	0	2.7	33.3	7.1
	Phonology only	3.6	5.0	0	0	14.3
	None	16.9	5.0	13.5	41.7	21.4

Abbreviations: AD, autistic disorder; AFs, autistic features; AS, Asperger’s syndrome; ASD, autism spectrum disorder; PDD-NOS, pervasive developmental disorder-not otherwise specified.

Table 6 Correlations and explained variance (r²) of VIQ and PIQ in relation to the language variables

	Sentence comprehension (RDLS)	Word comprehension (SPIQ)	Word analogies (ITPA)	Grammar (PT)	Phonological speech production (PSPA)	Phonological processing (NWRT)
VIQ: correlation	0.626**	0.563**	0.811**	0.541***	−0.309***	0.302**
r^2	0.392	0.317	0.658	0.293	0.095	0.091
n	82	82	65	80	80	77
PIQ: correlation	0.396**	0.312**	0.299**	0.294**	−0.194	0.274*
r^2	0.157	0.097	0.089	0.086	0.038	0.075
n	82	82	65	80	80	77

Notes:

* P<0.05 (Pearson, two-tailed);

** P<0.01 (Pearson two-tailed);

*** P<0.01 (Spearman, two-tailed).

Abbreviations: ITPA, Illinois Test of Psycholinguistic Abilities; NWRT, nonword-repetition task; PT, Processability Test; PSPA, phonological speech-production assessment; RDLS, Reynell Developmental Language Scale; SPIQ, Snabbt Performancetest på Intelligence (IQ).