Table 4. Odds Ratios for the Prediction of Consistency Between Index and Reference ASD Diagnoses Using Child- and Clinician-Based Predictors Using Multivariate Multilevel Modela.
| Parameter fixed effects | Model 1 | Model 2 | Model 3 | Model 4 | Model 5 |
|---|---|---|---|---|---|
| Predicted intercept | 2.135b | 2.777b | 1.014b | 0.239 | 0.029 |
| Child-level predictor | |||||
| Certainty | NA | 1.794b | 1.536b | 1.631b | 1.817b |
| Ethnicity | NA | NA | 2.659b | 2.796b | 2.459c |
| Child directly observed | NA | NA | NA | 1.947b | 2.312b |
| Clinician-level predictor | |||||
| Sex | NA | NA | NA | NA | 3.084 |
| Age | NA | NA | NA | NA | 1.004 |
| Years past training | NA | NA | NA | NA | 0.970 |
| ASD primary responsibility | NA | NA | NA | NA | 2.156 |
| ADOS routinely used | NA | NA | NA | NA | 0.933 |
| Model improvementd | |||||
| Deviance based χ2 | 837.701 | 54.812 | 20.838 | 121.760 | NA |
| df | 2 | 3 | 4 | 1 | NA |
| P value | NA | <.001 | <.001 | <.001 | NA |
Abbreviations: ADOS, Autism Diagnostic Observation Schedule, ASD; autism spectrum disorder; NA, not applicable.
a
Valid cases in the multivariate model were n = 341, thus, there were 8 missing cases (0.023%) and were due to listwise deletion required by the multivariate model.
b
P < .05, 2-tailed test.
c
P < .05, 1-tailed test.
d
Variance reduction by use of a χ2 test based on the difference in the 2 models’ deviance estimates. Nested models involve only significant parameters in the multivariate model using either 1-tailed or 2-tailed. NA in model 5 denotes the absence of a comparison model 6.