Table 1.
Demographics and clinical characteristics
| Demographics | ASD (n = 30) | TD (n = 34) | ASD versus TD | ||||
|---|---|---|---|---|---|---|---|
| Concordant twin pairs | M | SD | M | SD | t or χ2 | P | |
| Age (years) | 10.90 | 2.80 | 9.59 | 2.69 | 1.91 | 0.06 | |
| Sex (male/female) | 24/6 | - | 24/10 | - | 0.75 | 0.39 | |
| Ethnicity (A/B/H/W/MO) | 2/1/3/19/5 | - | 2/0/1/27/4 | - | 3.27 | 0.51 | |
| SES (Hollingshead) | 50.22 | 11.86 | 55.52 | 8.60 | −2.03 | 0.05* | d |
| Clinical characteristics | ASD (n = 96) | TD (n = 68) | ASD versus TD | ||||
| Individuals | M | SD | M | SD | t or χ2 | P | |
| Handedness (right/left) | 85/11 | - | 62/6 | - | 0.30 | 0.59 | |
| Full scale IQ | 86.40 | 25.85 | 112.99 | 11.53 | −7.92 | <0.001† | c,d |
| Sensory Processing (SSP) | 149.33 | 25.54 | 175.10 | 14.85 | −7.05 | <0.001† | c,d |
| SRS | 67.15 | 17.47 | 43.63 | 5.49 | 10.64 | <0.001† | a,b,c,d |
| ADI-R diagnostic total | 33.99 | 18.91 | - | - | - | - | |
| ADOS-2 comp. score | 6.27 | 2.84 | - | - | - | - | |
The current samples are comprised of twin pairs in which both twins were concordant for ASD or were TD control twin pairs or all individuals, including those discordant for ASD. Mean (M) and standard deviations (SD) or counts within each category are presented. ADI-R diagnostic total is the sum of the social interaction, communication, and restricted/repetitive behavior subscales . ADOS-2 comp. score is the standardized comparison score across modules. Group comparisons (ASD vs. TD) were conducted with independent samples t tests (t) or chi-squared (χ2). A/B/H/W/MO = Asian/Black/Hispanic/White/multiple or other. Significant group comparison at *P < 0.05 or †false discovery rate (Benjamini and Hochberg 1995) corrected across the tests within each column is indicated.
a = MZ ASD vs. DZ ASD P ≤ 0.05,
b = MZ TD vs. DZ TD P ≤ 0.05,
c = MZ ASD vs. MZ TD P ≤ 0.05,
d = DZ ASD vs. DZ TD P ≤ 0.05