Table 2.
Sex Differences on Measures of Restricted and Repetitive Behaviors and Social Communication in Children with ASD
| Category | Outcome | Inclusion Criteria |
Sample Composition |
Model Selection | Marginal Mean (SE) | ||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| AIC | BIC | Deviance | Contrast | Boys | Girls | Difference (ES) |
|||||
| Restricted & Repetitive Behaviors | ADOS RRB CSS | Module 1 & Age >= 31 months; Mod 2 & Age >= 12 mo; Mod 3 & Age > 36 mo | 6,711 Boys | Exclude | 33516 | 33656 | 33476 | Age 3 yrs: | 7.6 (0.2) | 7.4 (0.2) | 0.2* (0.12) |
| 1,280 Girls | Include | 33478 | 33639 | 33432 | Age 7 yrs: | 7.3 (0.1) | 6.9 (0.2) | 0.3*** (0.16) | |||
| 27 Sites (ICC=0.09) | ΔDev(3)=44.4*** | Age 15 yrs: | 7.7 (0.2) | 6.9 (0.3) | 0.8*** (0.39) | ||||||
| ADI-R RRB Current | Age < 48 months (Toddler Algorithm) | 769 Boys | Exclude | 4078 | 4126 | 4058 | No Evidence for an Effect | ||||
| 174 Girls | Include | 4078 | 413666 | 4054 | |||||||
| 9 Sites (ICC=0.15) | ΔDev(2)=4.5 | ||||||||||
| Age >= 48 months | 4016 Boys | Exclude | 22173 | 22263 | 22145 | Age 5 yrs: | 4.8 (0.2) | 4.3 (0.3) | 0.5*** (0.21) | ||
| 750 Girls | Include | 22156 | 22265 | 22122 | Age 10 yrs: | 5.0 (0.3) | 4.6 (0.3) | 0.5** (0.18) | |||
| 14 Sites (ICC=0.06) | ΔDev(3)=23.0*** | Age 15 yrs: | 4.6 (0.4) | 4.6 (0.4) | −0.0 (−0.01) | ||||||
| SRS RRB | Age >= 48 months | 2,965 Boys | Exclude | 23190 | 23276 | 23162 | Age 5 yrs: | 15.3 (1.8) | 14.6 (1.9) | 0.7 (0.09) | |
| 517 Girls | Include | 23180 | 23285 | 23146 | Age 10 yrs: | 18.4 (1.9) | 17.8 (1.9) | 0.6 (0.08) | |||
| 6 Sites (ICC=0.29) | ΔDev(3)=15.3** | Age 15 yrs: | 17.5 (2.0) | 19.7 (2.1) | −2.2** (−0.28) | ||||||
| Social Communication | ADOS SA CSS | Module 1 & Age >= 31 months; Mod 2 & Age >= 12 mo; Mod 3 & Age > 36 mo | 6650 Boys | Exclude | 32581 | 32720 | 32541 | Age 3 yrs: | 6.8 (0.1) | 6.9 (0.1) | −0.2 (−0.08) |
| 1268 Girls | Include | 32577 | 32737 | 32531 | Age 7 yrs: | 7.0 (0.1) | 6.8 (0.1) | 0.2* (0.10) | |||
| 27 Sites (ICC=0.03) | ΔDev(3)=9.9* | Age 15 yrs: | 7.6 (0.2) | 7.5 (0.3) | 0.1 (0.05) | ||||||
| ADI-R SI Current | Age < 48 months (Toddler Algorithm) | 750 Boys | Exclude | 5499 | 5547 | 5479 | No Evidence for an Effect | ||||
| 170 Girls | Include | 5502 | 5559 | 5478 | |||||||
| 8 Sites† | ΔDev(2)=1.2 | ||||||||||
| Age >= 48 months | 4009 Boys | Exclude | 28521 | 28612 | 28493 | No Evidence for an Effect | |||||
| 746 Girls | Include | 28527 | 28637 | 28493 | |||||||
| 14 Sites (ICC=0.04) | ΔDev(3)=0.5 | ||||||||||
| ADI-R Communication POMP Current | Age < 48 months (Toddler Algorithm) | 742 Boys | Exclude | 7769 | 7817 | 7749 | No Evidence for an Effect | ||||
| 168 Girls | Include | 7772 | 7829 | 7748 | |||||||
| 8 Sites (0.002) | ΔDev(2)=1.6 | ||||||||||
| Age >= 48 months | 4016 Boys | Exclude | 40991 | 41082 | 40963 | No Evidence for an Effect | |||||
| 750 Girls | Include | 40994 | 41104 | 40960 | |||||||
| 14 Sites (ICC=0.06) | ΔDev(3)=3.0 | ||||||||||
| SRS SCI | Age >= 48 months | 2,911 Boys | Exclude | 30367 | 30453 | 30339 | Age 5 yrs: | 70.6 (4.5) | 71.7 (4.8) | −1.1 (−0.05) | |
| 506 Girls | Include | 30360 | 30465 | 30326 | Age 10 yrs: | 75.9 (4.8) | 76.9 (4.9) | −1.0 (−0.04) | |||
| 6 Sites (ICC=0.21) | ΔDev(3)=12.3** | Age 15 yrs: | 76.5 (5.5) | 83.8 (5.7) | −7.4*** (−0.32) | ||||||
ICC is reported for the model including sex. For the ICC excluding sex, see Supplementary Tables 3a and 3b. Least-square means are calculated at pre-specified ages, averaging over the indicator variable for language status and over NVIQ, estimating contrasts at NVIQ of 70, 85, and 100.
See Tables S3a and S3b for list of terms in each model.
ADI-R = Autism Diagnostic Interview-Revised, ADOS = Autism Diagnostic Observation Schedule, ASD = autism spectrum disorder, CSS = Calibrated severity score, RRB = Restricted and Repetitive Behaviors, SA = Social Affect, SCI = Social Communication/Interaction, SRS = Social Responsiveness Scale
Random-intercept model was singular, resulting in an ICC=0. To ensure robust results, the model was refit with fixed-effects for site and without any site effect, neither of which modified the conclusions of the model.
p<0.05
p<0.01
p<0.001