Table 3.
Characterization of Subgroups of High-Risk Siblings Based on Classification and Regression Tree (CART) Analysis at 18 Months
| Leaf (Label) |
n | % Boys | Age of recruitment (months) |
Age of assessment (months) |
Severity 18m |
Severity 36m |
VDQ 18m |
VDQ 36m |
NVDQ 18m |
NVDQ 36m |
|---|---|---|---|---|---|---|---|---|---|---|
| A (TD) | 220 | 44.1 | 7.4 (4.6) | 18.3 (.6) | 1.5 (.9) | 2.1*** (1.7) | 100 (28) | 104 (16) | 105 (11) | 109 (16) |
| B (ATYP) | 11 | 72.7 | 7.2 (2.3) | 18.2 (.4) | 1.6 (1.2) | 4.6** (1.9) | 108 (7) | 106 (15) | 117 (12) | 105 (13) |
| C (TD) | 134 | 63.9 | 7.5 (3.7) | 18.3 (.5) | 1.9 (1.1) | 2.9*** (2.4) | 97 (20) | 101 (17) | 105 (12) | 103 (16) |
| D (ASD) | 10 | 90.0 | 9.2 (4.7) | 18.2 (.6) | 3.2 (1.5) | 6.4** (2.8) | 83 (25) | 84 (28) | 93 (19) | 90 (29) |
| E (TD) | 46 | 58.7 | 7.8 (3.4) | 18.4 (.5) | 3.7 (1.4) | 2.7 (2.2) | 85 (17) | 104*** (14) | 102 (8) | 105 (16) |
| F (ASD) | 31 | 71.0 | 7.4 (3.2) | 18.5 (.6) | 4.8 (1.7) | 4.1 (2.7) | 85 (24) | 93 (28) | 102 (10) | 97 (19) |
| G (TD) | 40 | 57.9 | 7.9 (3.3) | 18.4 (.5) | 4.6 (1.3) | 4.1 (2.4) | 84 (16) | 99** (19) | 105 (12) | 98 (17) |
| H (ASD) | 73 | 74.0 | 8.1 (3.8) | 18.5 (.7) | 6.1 (1.9) | 6.1 (2.6) | 62 (21) | 77** (26) | 92 (13) | 84 (21) |
Note: Post hoc comparisons between scores at 18 and 36 months with Bonferroni correction for multiple comparisons. Variables associated with significantly different comparisons are boldface within each row. Excepting n and % Boys, variables are reported as means and standard deviation: m(SD). ASD = autism spectrum disorder; ATYP = atypical development; NVDQ = nonverbal developmental quotient; TD = typical development; VDQ = verbal developmental quotient.
***
p<.0001,
**
p<.001