TABLE 2.
Phenotypic Presentation of Study Participants
| Subgroup Comparisons | |||||||
|---|---|---|---|---|---|---|---|
| Variable | Overall Group | ASD | ASD-Inclusive | Non-ASD | P Valuea | ||
| Participants, n | 1000b | 533 | 318 | 101 | |||
| Age at diagnosis, mean (SD), y | 5.92 (6.0) | 5.71 (5.8) | < | 6.80 (6.6) | N/A | .083 | |
| Age at enrollment, mean (SD), y | 13.7 (9.6) | 13.2 (9.0) | ≈ | 14.0 (9.8) | ≈ | 15.4 (11.8) | .079 |
| VABS-II, mean (SD) | |||||||
| Communication | 71.5 (22.0) | 68.05 (20.8)f | < | 75.23 (21.7)e | ≈ | 81.66 (24.5)e | <.001 |
| Daily living skills | 73.35 (21.2) | 70.37 (20.3)f | < | 77.69 (21.7)e | ≈ | 79.28 (20.9)e | <.001 |
| Social skills | 65.95 (19.7) | 63.19 (18.2)f | < | 69.50 (20.8)e | ≈ | 72.49 (21.2)e | <.001 |
| Motor skillsc | 79.85 (19.3) | 79.35 (18.9) | ≈ | 79.80 (20.9) | ≈ | 85.08 (18.0) | .619 |
| ABC | 68.64 (19.1) | 65.59 (17.7)f | < | 72.53 (20.0)e | ≈ | 75.96 (19.7)e | <.001 |
| ADOS-2, mean (SD) | |||||||
| Severity | 6.25 (2.5) | 7.31 (1.7)g | > | 5.47 (2.4)f | > | 2.10 (0.8)e | <.001 |
| ADOS-2 classification, n (%) | |||||||
| Autism | 600 (60.0) | 469 (88.0) | 131 (56.0) | 0 (0.0) | <.001 (χ2) | ||
| ASD | 113 (11.3) | 64 (12.0) | 49 (20.9) | 0 (0.0) | |||
| Non-spectrum | 141 (14.1) | 0 (0.0) | 54 (23.1) | 87 (86.1) | |||
| Data not available | 146 (14.6) | 84 (26.4) | 14 (13.9) | ||||
| SRS-2, mean (SD) | |||||||
| RRB | 76.01 (11.7) | 77.04 (10.5)f | ≈ | 74.97 (12.2) | ≈ | 73.16 (15.3)e | .012 |
| SCI | 74.35 (11.2) | 75.13 (10.1)f | ≈ | 74.09 (11.6)f | > | 70.56 (15.1)e | .005 |
| Total | 75.35 (11.1) | 76.24 (9.9)f | ≈ | 74.82 (11.4) | ≈ | 71.70 (15.2)e | .004 |
| Expressive language by parent report, n (%) | |||||||
| Verbal | 746 (74.8) | 422 (83.9) | 236 (88.7) | 88 (95.7) | .025 (χ2) | ||
| Nonverbal | 109 (11.0) | 76 (15.1) | 29 (10.9) | 4 (4.3) | |||
| Unsure | 6 (0.6) | 5 (1.0) | 1 (0.4) | 0 (0.0) | |||
| Data not available | 136 (13.6) | 30 (5.6) | 52 (16.4) | 9 (8.9) | |||
| Expressive language by ADOS-2 item A1, n (%)d | |||||||
| Minimally verbal | 115 (11.5) | 94 (17.6) | 19 (6.0) | 2 (2.0) | <.001 (χ2) | ||
| Single word speech | 92 (9.2) | 66 (12.4) | 21 (6.6) | 5 (5.0) | |||
| Phrase speech | 125 (12.5) | 92 (17.3) | 29 (9.1) | 4 (4.0) | |||
| Complex speech | 523 (52.3) | 281 (52.7) | 165 (51.9) | 77 (76.2) | |||
| Data not available | 145 (14.5) | 84 (26.4) | 13 (12.9) | ||||
Abbreviations: ABC, adaptive behavior composite; ADOS, Autism Diagnostic Observation Schedule; ADOS-2, Autism Diagnostic Observation Schedule, Second Edition; ASD, autism spectrum disorder; Dx, diagnosis; N/A, not applicable; RRB, restricted, repetitive behavior; SCI, social communication and interaction; SD, standard deviation; SRS-2, Social Responsiveness Scale, Second Edition; VABS-II, Vineland Adaptive Behavior Scales, Second Edition; y, years.
P values for overall tests are reported. Tests of mean differences utilized ANOVA. Chi-square tests are denoted in the table.
Neither an ADOS-2 nor a community diagnosis was available for 48 individuals in the registry. Therefore, these individuals were not included in any of the subgroups.
Motor skills scores were only collected for a subset of participants, namely, those who were either < 6 years old or > 50 years old.
Language level from ADOS-2 was defined as follows from item A1 on each module. Minimally verbal: Module 1 scores 4 or 3; Single word speech: Module 1 scores 2 or 1, Module 2 score 3; Phrase speech: Module 2 scores 2, 1, or 0, Modules 3 and 4 scores 2 or 3; Complex speech: Modules 3 and 4, scores 1 or 0.
Significant between subgroup post-hoc tests are indicated by letter notation with significant pairwise comparisons (Tukey) indicated by differing letter notations and by appropriate notation between columns (>, <, or ≈) to indicate direction of differences between subgroups.