Table 3.
Clinical characteristics for children with a diagnosis of autism spectrum disorder (ASD) enrolled in the Study to Explore Early Development (SEED), excluding intellectual disability (ID), compared to those with developmental delay (DD) with likely, possible, some, or no social communication disorder (SCD) based on selected items from the Autism Diagnostic Interview-Revised (ADI-R).
| Variable | ASD No ID | DD Likely SCD | ASD vs. Likely SCD | DD Possible SCD | DD Some SCD | DD No SCD | Likely SCD vs. No SCD |
|---|---|---|---|---|---|---|---|
| N=642 | N=117 | Comparison | N=118 | N=126 | N=91 | Comparison | |
| SCQa | missing=1 | missing=1 | |||||
| Proportion meeting screening criterion | 0.80 | 0.90 | t(755)= −2.6 | 0.81 | 0.72 | 0.86 | t(205)=0.9 |
| (SD=0.40) | (SD=0.31) | Diff.b= −0.1 | (SD=0.39) | (SD=0.48) | (SD=0.35) | Diff.= 0.0 | |
| CIc=−0.2, −0.0 | CI=−0.1, 0.1 | ||||||
| adj.p=.086 | adj.p>.999 | ||||||
| ADOSd | |||||||
| Social Affect | 7.9* | 2.4 | t(757)= 22.5 | 3.6 | 3.5 | 2.1 | t(206)=1.0 |
| (SD=2.5) | (SD=2.0) | Diff.=5.5 | (SD=2.8) | (SD=2.8) | (SD=2.5) | Diff.=0.3 | |
| CI=5.1, 5.9a | CI= −0.3, 0.9 | ||||||
| dj. p<.001 | adj.p>.999 | ||||||
| Restricted/Repetitive | 3.1* | 1.2 | t(757)=12.3 | 1.6 | 1.6 | 0.77* | t(206)=2.9 |
| Behavior (RRB) | (SD=1.6) | (SD=1.1) | Diff.= 1.9 | (SD=1.4) | (SD=1.5) | (SD=1.0) | Diff.= 0.4 |
| CI= 1.7, 2.1 | CI=0.1, 0.7 | ||||||
| adj.p<.00l | adj.p=.040 | ||||||
| ADI-Re | |||||||
| Social | 17.0* | 14.8 | t(757)=4.0 | 7.3 | 4.7 | 1.8* | t(206)= 23.4 |
| (SD=5.6) | (SD=5.1) | Diff.= 2.2 | (SD=2.2) | (SD=1.8) | (SD=1.6) | Diff.= 13.0 | |
| CI= 1.2, 3.2 | CI=12.0, 14.0 | ||||||
| adj. p<.001 | adj.p<.001 | ||||||
| Communication | 14.3 | 13.2 | t(757)= 2.6 | 8.2 | 5.8 | 2.4* | t(206)= 24.3 |
| (SD=4.2) | (SD=3.9) | Diff.= l.l | (SD=2.9) | (SD=2.2) | (SD=1.9) | Diff.= 10.8 | |
| CI=0.3, 1.9 | CI=10.0, 11.6 | ||||||
| adj.p=.077 | adj.p<.001 | ||||||
| RRB | 6.4* | 5.3 | t(757)= 4.0 | 3.5 | 3.1 | 1.7* | t(206)= 10.4 |
| (SD=2.7) | (SD=3.0) | Diff.= l.l | (SD=2.5) | (SD=2.4) | (SD=1.6) | Diff.= 3.6 | |
| CI=0.5, 1.7 | CI= 3.0, 4.2 | ||||||
| adj.p.001 | adj.p<.001 | ||||||
| CBCLf– Problems | missing=20 | missing=3 | missing=5 | missing=5 | missing=2 | ||
| Internalizing | 62.3 | 63.6 | t(734)= −1.3 | 60.2 | 57.5 | 55.1* | t(201)= 5.2 |
| (SD=10.1) | (SD=10.5) | Diff.= −1.3 | (SD=11.7) | (SD=11.9) | (SD=12.7) | Diff.= 8.5 | |
| CI= −3.4, .08 | CI= 5.2, 11.8 | ||||||
| adj.p>.999 | adj.p<.00l | ||||||
| Externalizing | 58.8* | 62.5 | t(734)= −3.0 | 57.1 | 54.8 | 55.4* | t(201)= 3.7 |
| (SD=11.8) | (SD=13.7) | Diff.= −3.7 | (SD=13.4) | (SD=12.5) | (SD=13.8) | Diff= 7.1 | |
| CI= −6.4, −1.0 | CI= 3.3, 10.9 | ||||||
| adj.p=.031 | adj.p=.005 | ||||||
| Nonverbal | |||||||
| Cognition: MSELg -Visual Reception | 47.3 | 47.9 | t(757)=-0.6 | 45.1 | 47.4 | 43.9* | t(206)= 3.5 |
| (SD=9.6) | (SD=8.7) | Diff.= −0.6 | (SD=9.6) | (SD=9.4) | (SD=7.5) | Diff.= 4.0 | |
| CI= −2.3, 1.1 | CI= 1.8, 6.2 | ||||||
| adj.p<.999 | adj.p=.007 | ||||||
| Language – MSEL Receptive | |||||||
| 38.1 | 41.3 | t(757)= −2.5 | 40.6 | 41.0 | 40.1 | t(206)=0.7 | |
| (SD=12.9) | (SD=11.8) | Diff.= −3.2 | (SD=12.6) | (SD=11.9) | (SD=11.4) | Diff.= 1.2 | |
| CI= −5.6, −0.8 | CI= −2.0, 4.4 | ||||||
| adj.p=.088 | adj.p>.999 | ||||||
| Expressive | 34.9* | 39.3 | t(757)= −3.9 | 39.0 | 40.0 | 40.9 | t(206)= −1.1 |
| (SD=11.4) | (SD=10.2) | Diff.= −4.4 | (SD=10.8) | (SD=12.1) | (SD=10.6) | Diff.= −1.6 | |
| CI= −6.5, −2.3 | CI= −4.5, 1.3 | ||||||
| adj.p=.003 | adj.p>.999 | ||||||
| Prior ASD Diagnosis | missing=4 | missing=0 | missing=5 | missing=1 | missing=6 | ||
| 555 (86%)* | 57 (49%) | X21=94.3 | 50 (42%) | 52 (41%) | 19 (21%)* | X21=14.6 | |
| p<.001 | p<.001 |
SCQ= Social Communication Questionnaire (Rutter, Bailey, & Lord, 2003), proportion with score ≥11;
Diff. = observed group difference,
CI = 95% confidence interval,
ADOS=Autism Diagnostic Observation Schedule (Lord, Rutter, DiLavore, & Risi, 1999, 2000, 2001 WPS version), mean algorithm scores (and standard deviations, SD) for both domains;
ADI-R=Autism Diagnostic Interview-Revised (Lord, Rutter, & Couteur, 1994, 2003 WPS version), mean (and SD) algorithm scores for each domain;
CBCL=Child Behavior Checklist (Achenbach, 1992, 2000 Aseba version), mean (and SD) Problems scale t-score;
MSEL=Mullen Scales of Early Learning (Mullen, 1995), mean (and SD) t-scores for the visual reception, receptive language, and expressive language scales
Denotes statistically significant difference in score for that group compared to Likely SCD group score