Table 1. Participants’ Characteristics.
| Variable | Control (n = 39) | At-risk (n = 47) | At-risk typical (n = 18) | At-risk atypical (n = 12) | At-risk ASD (n = 17) |
|---|---|---|---|---|---|
| Note. ASD = autism spectrum disorder; Mullen = Mullen Scales for Early Learning (Mullen, 1995); ADOS = Autism Diagnostic Observation Schedule—Generic (Lord et al., 2000); ADI = Autism Diagnostic Interview—Revised (Lord et al., 1994). Superscripts on data indicate differences between low and high risk (* p < .05; ** p < .01) and between the at-risk ASD or atypical groups and at-risk TD (+ p < .05; ++ p < .01; Bonferroni correction). | |||||
| a Mullen ELC score, M = 100, SD = 15. b Verbal ability T-score, M = 50, SD = 10 (based on average of Expressive and Receptive Language domains). c The Social and Communication algorithm score of the ADOS. d Overall household income. e Mother’s education level (1 = formal education to 16; 2 = formal education to 18; 3 = university degree or equivalent; 4 = postgraduate). Missing data for Education level (seven data points) were replaced by the average of the risk group. | |||||
| Age (months) | |||||
| M (SD) | 39.5 (3.3) | 38.0 (1.7)* | 37.9 (1.5) | 37.5 (1.7) | 38.6 (2.0) |
| Range | 36–52 | 33–42 | 34–40 | 33–40 | 35–42 |
| Gender | |||||
| Male | 21 | 27 | 12 | 9 | 6 |
| Female | 18 | 20 | 6 | 3 | 11 |
| General IQ (Mullen)a | |||||
| M (SD) | 114.7 (16.1) | 104.2 (22.5)* | 113.2 (15.0) | 103.4 (18.9) | 94.7 (28.5)++ |
| Range | 72–137 | 49–147 | 86–142 | 63–126 | 49–147 |
| Verbal IQ (Mullen)b | |||||
| M (SD) | 57.5 (8.5) | 51.2 (12.0)* | 55.9 (14.5) | 49.8 (8.6) | 47.2 (15.9) |
| Range | 41–69 | 29–73 | 43–69 | 29–64 | 20–73 |
| ADOS SCc | |||||
| M (SD) | 5.5 (4.5) | 8.8 (5.3)** | 4.1 (2.0) | 12.0 (4.0)++ | 11.4 (5.0)++ |
| Range | 0–21 | 0–19 | 0–7 | 5–18 | 1–19 |
| ADI Social | |||||
| M (SD) | 5.0 (5.4) | 1.9 (1.7) | 3.4 (4.9) | 9.7 (5.5)++ | |
| Range | 0–5 | 0–18 | 1–19 | ||
| ADI Communication | |||||
| M (SD) | 4.5 (4.9) | 2.2 (1.8) | 3.5 (5.4) | 8.2 (5.2)++ | |
| Range | 0–6 | 0–20 | 1–16 | ||
| Ethnicity | |||||
| Caucasian | 33 | 41 | 17 | 9 | 14 |
| Caucasian/Asian | 2 | 2 | 1 | 1 | |
| Caucasian/Latino | 1 | 1 | 1 | ||
| Caucasian/Black | 1 | 1 | 1 | ||
| Asian | 1 | ||||
| Black | 1 | 1 | 1 | ||
| Mixed | 1 | 1 | 1 | ||
| Incomed | |||||
| <40K | 9 | 17 | 4 | 8 | 5 |
| 40–80K | 14 | 23 | 8 | 3 | 12 |
| >80K | 16 | 7 | 6 | 1 | 0 |
| Educatione | |||||
| M (SD) | 3.0 (0.9) | 2.7 (0.9) | 2.8 (0.9) | 3.0 (0.9) | 2.4 (0.9) |
| Range | 1–4 | 1–4 | 1–4 | 1–4 | 1–4 |