Table 1.
Summary of characteristics for the four trajectory groups at early childhood behavioral assessments
| Variable | High Challenges (n = 26) |
Stable Low (n = 18) |
Changers (n = 36) |
Lesser Challenges (n = 22) |
|---|---|---|---|---|
| Male | 22 (85%) | 17 (94%) | 25 (75%) | 16 (73%) |
| Age at IQ testing (months) | ||||
| Age 2–3.5 years | 35.6 (5.6) | 32.9 (4.5) | 34.1 (4.8) | 34.4 (6.3) |
| Age 6–7.5 years | 68.8 (9.8) | 66.6 (10.4) | 67.1 (9.9) | 67.1 (11.6) |
| Time between IQ tests (months) | ||||
| 33.2 (7.5) | 33.7 (8.8) | 32.9 (8.3) | 32.7 (6.8) | |
| ADOS CSS ≤3 at T2 | 0 (0%) | 0 (0%) | 2 (6%) | 3 (14%) |
| PPD-NOS | 0 (0%) | 1 (6%) | 3 (8%) | 4 (18%) |
| ADOS Severity | ||||
| Age 2–3.5 years | 8.2 (1.6)a | 7.2 (1.6) | 7.0 (1.8) | 6.8 (1.7)b |
| Age 6–7.5 years | 8.3 (1.2)a | 8.3 (1.5)a | 6.7 (2.0)b | 5.4 (2.0)c |
| Verbal IQ Score < 70 | ||||
| Age 2–3.5 years | 25 (96%)* | 15 (83%)* | 27 (75%)* | 0 (0%)* |
| Age 6–7.5 years | 26 (100%)* | 11 (61%)* | 0 (0%)* | 0 (0%)* |
| Non-Verbal IQ Score < 70 | ||||
| Age 2–3.5 years | 24 (92%)* | 7 (39%)* | 21 (58%)* | 0 (0%)* |
| Age 6–7.5 years | 26 (100%)* | 9 (50%)* | 0 (0%)* | 0 (0%)* |
| VABS communication domain | ||||
| Age 2–3.5 years1 | 63.5 (12.1)a | 73.7 (15.2)b | 77.7 (11.4)b | 87.9 (11.1)c |
| Age 6–7.5 years2 | 56.7 (12.7)a | 81.4 (11.4)b | 90.8 (13.6)b,c | 95.0 (11.4)c |
| CBCL Externalizing | ||||
| Age 2–3.5 years3 | 55.6 (8.4) | 62.1 (10.2) | 61.5 (11.2) | 56.8 (12.6) |
| Age 6–7.5 years4 | 56.2 (10.3) | 58.2 (7.7) | 53.8 (9.3) | 54.6 (10.2) |
| CBCL Internalizing | ||||
| Age 2–3.5 years3 | 60.7 (7.0) | 63.2 (8.2) | 62.5 (9.5) | 63.7 (10.0) |
| Age 6–7.5 years4 | 58.5 (9.2) | 56.6 (8.5) | 58.4 (12.8) | 60.7 (9.4) |
ADOS = Autism Diagnostic Observation Schedule; CBCL Child Behavior Checklist; VABS = Vineland Adaptive Behavior Scales.
*
Fisher’s exact test p-value < 0.05;
a,b,c
Groups with different superscripts differ significantly (p < .05) after Tukey-Kramer multiple comparison adjustment
1
Missing data = 3 in High Challenges, 1 in Stable Low, and 1 in Changers;
2
Missing data = 1 in High Challenges, 3 in Stable Low, 5 in Changers and 1 in Lesser Challenges;
3
Missing data = 1 in High Challenges, 1 in Stable Low, and 2 in Changers;
4
Missing data = 5 in High Challenges, 3 in Stable Low, 5 in Changers and 3 in Lesser Challenges.