Table 2. Autism Spectrum Disorder: Estimated Variance Componentsa and Associated 2-Sided 95% CI for Denmark, Finland, Sweden, and Nordic Countries Combinedb.
| Model and Population | Random Effects (95% CI) | |||
|---|---|---|---|---|
| Additive Genetic (A) | Shared Environment (C) | Maternal (M) | Nonshared Environment (E) | |
| Model 1: A + E | ||||
| Country specific | ||||
| Denmark | 80.7 (74.1-85.4) | NA | NA | 19.3 (14.6-25.9) |
| Finland | 80.8 (73.2-85.5) | NA | NA | 19.2 (14.5-26.8) |
| Sweden | 84.1 (79.7-88.1) | NA | NA | 16.0 (11.9-20.4) |
| Nordic countries combined | 82.7 (79.1-86.0) | NA | NA | 17.3 (14.0-20.9) |
| Model 2: A + C + E | ||||
| Country specific | ||||
| Denmark | 80.4 (71.3-86.8) | 0.0 (0.0-4.6) | NA | 19.6 (12.9-25.3) |
| Finland | 52.8 (29.7-76.3) | 14.5 (4.5-29.2) | NA | 32.8 (17.6-51.1) |
| Sweden | 84.8 (76.2-88.7) | 0.1 (0.0-3.4) | NA | 15.1 (11.1-21.1) |
| Nordic countries combined | 82.2 (77.2-85.9) | 0.2 (0.0-2.3) | NA | 17.7 (13.9-26.5) |
| Model 3: A + C + M + E | ||||
| Country specific | ||||
| Denmark | 78.9 (65.4-84.3) | 0.1 (0.0-4.8) | 0.4 (0.0-6.9) | 20.6 (14.6-26.5) |
| Finland | 50.9 (25.1-75.6) | 14.0 (0.0-28.6) | 1.6 (0.0-13.4) | 33.6 (17.6-53.9) |
| Sweden | 81.1 (69.9-86.7) | 0.0 (0.0-3.7) | 1.4 (0.0-6.6) | 17.5 (12.5-22.5) |
| Nordic countries combined | 81.2 (73.9-85.3) | 0.3 (0.0-2.2) | 0.5 (0.0-3.5) | 18.1 (14.1-21.7) |
Abbreviation: NA, not applicable.
a
All estimates are recalculated to fraction of variation explained, the proportion of total variance explained by each random effect (eAppendix 2 in the Supplement).
b
Nordic countries combined are Denmark, Finland, and Sweden.