Table 1.
Sample characteristics by Typical and Elevated likelihood groups.
| EL group | TL group | Group difference | |
|---|---|---|---|
| 8 months | |||
| Sex (N girls:N boys) | 84:85 | 42:35 | χ2(1) = 0.496, p = 0.481 |
| Age in months | 8.23 (1.14) | 7.91 (1.34) | t(244) = −1.941, p = 0.053, d = −0.27 |
| MSEL | 102.46 (15.79) | 107.25 (12.59) | t(244) = 2.344, p = 0.020, d = 0.32 |
| IBQ-R-fear | 2.95 (1.15) | 2.54 (0.88) | t(233) = −2.735, p = 0.007, d = −0.39 |
| IBQ-R-perceptual sensitivity | 3.79 (1.27) | 3.81 (1.15) | t(186) = 0.109, p = 0.913, d = 0.02 |
| 14 months | |||
| Sex (N girls:N boys) | 82:84 | 41:34 | χ2(1) = 0.450, p = 0.502 |
| Age in months | 14.51 (1.32) | 14.35 (1.32) | t(239) = −0.870, p = 0.385, d = −0.12 |
| MSEL | 95.20 (15.57) | 104.81 (15.26) | t(244) = −1.941, p = 0.053, d = 0.62 |
| IBQ-R-fear | 3.47 (1.08) | 2.99 (0.88) | t(225) = −3.3381, p = 0.001, d = −0.48 |
| IBQ-R-perceptual sensitivity | 3.74 (1.23) | 4.13 (1.04) | t(198) = 2.178, p = 0.031, d = 0.33 |
| 24 months | |||
| Sex (N girls:N boys) | 79:79 | 38:35 | χ2(1) = 0.346, p = 0.556 |
| Age in months | 25.39 (1.99) | 24.21 (0.93) | t(229) = −4.822, p < 0.001, d = −0.68 |
| MSEL | 99.69 (20.13) | 115.55 (14.14) | t(221) = 5.913, p < 0.001, d = 0.86 |
| ADOS CSS SA | 3.05 (2.05) | 1.96 (0.60) | t(182) = −2.689, p = 0.008, d = −0.57 |
| ADOS CSS RRB | 4.09 (2.72) | 2.54 (2.20) | t(182) = −2.773, p = 0.006, d = −0.59 |
| ECBQ-shyness | 3.33 (1.05) | 2.90 (0.82) | t(206) = −2.997, p = 0.003, d = −0.44 |
| ECBQ-perceptual sensitivity | 3.32 (1.18) | 3.34 (1.13) | t(206) = 0.104, p = 0.917, d = 0.15 |
| 36 months | |||
| Sex (N girls:N boys) | 80:84 | 38:35 | χ2(1) = 0.329, p = 0.566 |
| Age in months | 38.43 (2.21) | 38.40 (2.65) | t(235) = −0.108, p = 0.914, d = −0.02 |
| MSEL | 103.39 (23.99) | 117.04 (15.91) | t(234) = 4.440, p < 0.001, d = 0.63 |
| ADOS CSS SA | 3.54 (2.63) | 3.33 (2.25) | t(235) = −0.603, p = 0.547, d = −0.08 |
| ADOS CSS RRB | 4.55 (2.64) | 3.71 (2.47) | t(235) = −2.296, p = 0.023, d = −0.32 |
| ADI-R social | 3.80 (4.97) | 0.96 (1.49) | t(186) = −2.836, p = 0.005, d = −0.61 |
| ADI-R communication | 4.07 (4.73) | 0.48 (1.05) | t(186) = −3.777, p < 0.001, d = −0.81 |
| ADI-R RRB | 1.43 (2.40) | 0.08 (0.28) | t(186) = −3.065, p = 0.003, d = −0.66 |
| SRS-RRB | 5.24 (7.19) | 1.58 (2.19) | t(223) = −4.220, p < 0.001, d = −0.60 |
| SRS-SCI | 35.48 (26.25) | 19.81 (9.24) | t(223) = −4.921, p < 0.001, d = −0.70 |
ADI-R: Autism Diagnostic Interview–Revised; ADOS: Autism Diagnostic Observation Schedule; ECBQ: Early Childhood Behavioural Questionnaire; IBQ-R: Infant Behavioural Questionnaire–Revised; MSEL ELC: Mullen Scales of Early Learning Early Learning Composite Standard Score; RRB: Restrictive and Repetitive Behaviours; SA: Social Affect; SCI: Social Communication Interaction; SD: standard deviation; SRS: Social Responsiveness Scale.