Table 1.
Characteristics of the IMPaCT Case-Control Study Sample, Kaiser Permanente Northern California
| Characteristic | All, N = 2569 | ASD, n = 311 | DD, n = 1291 | GP, n = 967 |
|---|---|---|---|---|
| Maternal Age at Birth, Years | 31.30 (5.21) | 31.67 (5.34) | 31.49 (5.32) | 30.92 (5.00) |
| Maternal Race/Ethnicity | ||||
| Asian | 534 (20.79%) | 64 (20.58%) | 266 (20.60%) | 204 (21.10%) |
| Black | 148 (5.76%) | 20 (6.43%) | 80 (6.20%) | 48 (4.96%) |
| Hispanic | 619 (24.09%) | 69 (22.19%) | 323 (25.02%) | 227 (23.47%) |
| Other | 107 (4.17%) | 11 (3.54%) | 52 (4.03%) | 44 (4.55%) |
| White | 1145 (44.57%) | 144 (46.30%) | 561 (43.45%) | 440 (45.50%) |
| Unknown | 16 (0.62%) | 3 (0.96%) | 9 (0.70%) | 4 (0.41%) |
| Maternal Education | ||||
| Less than high school | 66 (2.57%) | 5 (1.61%) | 38 (2.94%) | 23 (2.38%) |
| High school | 309 (12.03%) | 37 (11.90%) | 163 (12.63%) | 109 (11.27%) |
| College | 1527 (59.44%) | 192 (61.74%) | 757 (58.64%) | 578 (59.77%) |
| Postgraduate | 422 (16.43%) | 46 (14.79%) | 212 (16.42%) | 164 (16.96%) |
| Unknown | 245 (9.54%) | 31 (9.97%) | 121 (9.37%) | 93 (9.62%) |
| Parity | ||||
| 0 | 1164 (45.31%) | 167 (53.70%) | 561 (43.45%) | 436 (45.09%) |
| 1 | 880 (34.25%) | 87 (27.97%) | 451 (34.93%) | 342 (35.37%) |
| 2 | 373 (14.52%) | 38 (12.22%) | 195 (15.10%) | 140 (14.48%) |
| 3 | 105 (4.09%) | 11 (3.54%) | 60 (4.65%) | 34 (3.52%) |
| 4+ | 38 (1.48%) | 6 (1.93%) | 17 (1.32%) | 15 (1.55%) |
| Unknown | 9 (0.35%) | 2 (0.64%) | 7 (0.54%) | 0 (0%) |
| Plurality | ||||
| Singleton | 2468 (96.07%) | 294 (94.53%) | 1223 (94.73%) | 951 (98.34%) |
| Multiplea | 101 (3.93%) | 17 (5.47%) | 68 (5.27%) | 16 (1.65%) |
| Gestational Age | ||||
| <35 weeks (very preterm) | 61 (2.37%) | 8 (2.57%) | 46 (3.56%) | 7 (0.72%) |
| 35–37 weeks (preterm) | 214 (8.33%) | 32 (10.29%) | 130 (10.07%) | 52 (5.38%) |
| ≥38 weeks (term) | 2294 (89.30%) | 271 (87.14%) | 1115 (86.37%) | 908 (93.90%) |
| Child Sex | ||||
| Female | 1031 (40.13%) | 69 (22.19%) | 474 (36.72%) | 488 (50.47%) |
| Male | 1538 (59.87%) | 244 (77.81%) | 817 (63.28%) | 479 (49.53%) |
| Child Year of Birth | ||||
| 2011 | 330 (12.85%) | 32 (10.29%) | 178 (13.79%) | 120 (12.41%) |
| 2012 | 396 (15.41%) | 45 (14.47%) | 215 (16.65%) | 136 (14.06%) |
| 2013 | 663 (25.81%) | 79 (25.40%) | 326 (25.25%) | 258 (26.68%) |
| 2014 | 689 (26.82%) | 92 (29.58%) | 326 (25.25%) | 271 (28.02%) |
| 2015 | 483 (18.80%) | 63 (20.26%) | 238 (18.44%) | 182 (18.82%) |
| 2016 | 8 (0.31%) | 0 (0.00%) | 8 (0.62%) | 0 (0%) |
Values are presented as mean (SD) or n (%).
ASD, autism spectrum disorder; DD, other neurodevelopmental disorders; GP, general population control; IMPaCT, Immune and Metabolic Markers during Pregnancy and Child Development.
a
Only one child per multiple pregnancy was included in the analytic dataset.