TABLE 1.
Participant characteristics by cohorts included in the analysis of autism spectrum disorder (ASD) diagnosis
| Cohort 1 | Cohort 2 | Cohort 3 | Cohort 4 | Cohort 5 | Cohort 6 | Cohort 7 | Cohort 8 | Cohort 9 | Cohort 10 | Cohort 11 | |
|---|---|---|---|---|---|---|---|---|---|---|---|
| n | 1177 | 142 | 2208 | 1900 | 1503 | 510 | 176 | 397 | 1366 | 885 | 1891 |
| Type of study population | General population n (%) | General population n (%) | General population n (%) | ASD cases oversampled n (%) | General population n (%) | ASD enriched risk (preterm birth) n (%) | General population n (%) | ASD familial enriched risk n (%) | General population n (%) | ASD enriched risk (preterm birth) n (%) | General population n (%) |
| Child female | 562 (47.7) | 66 (46.5) | 1080 (48.9) | 416 (21.9) | 726 (48.3) | 239 (46.9) | 87 (49.4) | 151 (38.0) | 670 (49.0) | 434 (49.0) | 882 (46.6) |
| Missing | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 41 (2.7) | 0 (0.0) | 0 (0.0) | 26 (6.5) | 0 (0.0) | 0 (0.0) | 0 (0.0) |
| Year of birth of child | |||||||||||
| Before 1991 | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) |
| 1991–2000 | 0 (0.0) | 0 (0.0) | 0 (0.0) | 218 (11.5) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 536 (39.2) | 0 (0.0) | 0 (0.0) |
| 2001–2010 | 148 (12.6) | 81 (57.0) | 0 (0.0) | 1470 (77.4) | 1096 (72.9) | 0 (0.0) | 144 (81.8) | 179 (45.1) | 830 (60.8) | 885 (100.0) | 0 (0.0) |
| After 2010 | 1029 (87.4) | 61 (43.0) | 2208 (100.0) | 212 (11.2) | 310 (20.6) | 510 (100.0) | 32 (18.2) | 192 (48.4) | 0 (0.0) | 0 (0.0) | 1891 (100.0) |
| Missing | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 97 (6.5) | 0 (0.0) | 0 (0.0) | 26 (6.5) | 0 (0.0) | 0 (0.0) | 0 (0.0) |
| Child ASD diagnosis (yes) | 15 (1.3) | 10 (7.0) | 41 (1.9) | 826 (43.5) | 78 (5.2) | 55 (10.8) | 41 (23.3) | 81 (20.4) | 44 (3.2) | 61 (6.9) | 22 (1.2) |
| Source of ASD diagnosis | |||||||||||
| Measured at study visit using ADOS | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 1 (0.2) | 0 (0.0) | 330 (83.1) | 0 (0.0) | 61 (6.9) | 0 (0.0) |
| Measured at study visit using other tool | 0 (0.0) | 0 (0.0) | 0 (0.0) | 1900 (100.0) a | 1503 (100.0) | 0 (0.0) | 174 (98.9) | 67 (16.9) | 0 (0.0) | 0 (0.0) | 0 (0.0) |
| Parent or other caregiver reported at study visits | 8 (0.7) | 142 (100.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 509 (99.8) | 2 (1.1) | 0 (0.0) | 1366 (100.0) | 0 (0.0) | 14 (0.7) |
| Extracted from medical record or educational record | 7 (0.6) | 0 (0.0) | 2208 (100.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 8 (0.4) |
| Not applicable | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 824 (93.1) | 1869 (98.8) |
| Missing | 1162 (98.7) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) |
| Neonatal complications (yes) | 425 (36.1) | 38 (26.8) | 1741 (78.8) | 316 (16.6) | 116 (7.7) | 350 (68.6) | 0 (0.0) | 23 (5.8) | 0 (0.0) | 885 (100.0) | 70 (3.7) |
| Missing | 39 (3.3) | 0 (0.0) | 0 (0.0) | 1503 (79.1) | 0 (0.0) | 0 (0.0) | 176 (100.0) | 374 (94.2) | 1366 (100.0) | 0 (0.0) | 0 (0.0) |
| Maternal age in years, mean (SD) | 27.8 (6.3) | 20.9 (2.8) | 30.8 (5.1) | 30.6 (5.8) | 26.8 (5.4) | 28.8 (6.4) | 25.6 (4.9) | 34.1 (4.8) | 32.7 (5.2) | 29.2 (6.7) | 31.5 (5.2) |
| Missing | 0 | 0 | 0 | 0 | 97 | 8 | 0 | 28 | 0 | 0 | 0 |
| Maternal race | |||||||||||
| White | 883 (75.0) | 6 (4.2) | 592 (26.8) | 1540 (81.1) | 467 (31.1) | 243 (47.6) | 128 (72.7) | 251 (63.2) | 1028 (75.3) | 545 (61.6) | 910 (48.1) |
| Black | 187 (15.9) | 0 (0.0) | 121 (5.5) | 93 (4.9) | 936 (62.3) | 97 (19.0) | 35 (19.9) | 23 (5.8) | 219 (16.0) | 237 (26.8) | 70 (3.7) |
| Asian | 41 (3.5) | 1 (0.7) | 429 (19.4) | 144 (7.6) | 13 (0.9) | 36 (7.1) | 0 (0.0) | 40 (10.1) | 68 (5.0) | 15 (1.7) | 121 (6.4) |
| Native Hawaiian or other Pacific islander | 0 (0.0) | 11 (7.7) | 18 (0.8) | 6 (0.3) | 1 (0.1) | 2 (0.4) | 0 (0.0) | 2 (0.5) | 0 (0.0) | 0 (0.0) | 2 (0.1) |
| American Indian or Alaska Native | 10 (0.8) | 32 (22.5) | 5 (0.2) | 11 (0.6) | 1 (0.1) | 9 (1.8) | 3 (1.7) | 3 (0.8) | 0 (0.0) | 12 (1.4) | 5 (0.3) |
| Multiple race | 53 (4.5) | 18 (12.7) | 372 (16.8) | 106 (5.6) | 77 (5.1) | 70 (13.7) | 8 (4.5) | 23 (5.8) | 43 (3.1) | 0 (0.0) | 28 (1.5) |
| Other race | 3 (0.3) | 73 (51.4) | 555 (25.1) | 0 (0.0) | 6 (0.4) | 48 (9.4) | 0 (0.0) | 13 (3.3) | 2 (0.1) | 54 (6.1) | 210 (11.1) |
| Missing | 0 (0.0) | 1 (0.7) | 116 (5.3) | 0 (0.0) | 2 (0.1) | 5 (1.0) | 2 (1.1) | 42 (10.6) | 6 (0.4) | 22 (2.5) | 545 (28.8) |
| Maternal ethnicity—Hispanic | 291 (24.7) | 13 (9.2) | 781 (35.4) | 482 (25.4) | 32 (2.1) | 106 (20.8) | 16 (9.1) | 66 (16.6) | 108 (7.9) | 86 (9.7) | 766 (40.5) |
| Missing | 2 (0.2) | 100 (70.4) | 120 (5.4) | 0 (0.0) | 9 (0.6) | 4 (0.8) | 2 (1.1) | 40 (10.1) | 6 (0.4) | 2 (0.2) | 277 (14.6) |
| Maternal education | |||||||||||
| High school or less | 0 (0.0) | 125 (88.0) | 219 (9.9) | 507 (26.7) | 893 (59.4) | 198 (38.8) | 18 (10.2) | 34 (8.6) | 116 (8.5) | 353 (39.9) | 560 (29.6) |
| Some college | 0 (0.0) | 16 (11.3) | 584 (26.4) | 575 (30.3) | 138 (9.2) | 176 (34.5) | 13 (7.4) | 110 (27.7) | 298 (21.8) | 201 (22.7) | 204 (10.8) |
| Bachelor's degree or above | 0 (0.0) | 1 (0.7) | 924 (41.8) | 801 (42.2) | 470 (31.3) | 124 (24.3) | 2 (1.1) | 223 (56.2) | 946 (69.3) | 305 (34.5) | 830 (43.9) |
| Missing | 1177 (100.0) | 0 (0.0) | 481 (21.8) | 17 (0.9) | 2 (0.1) | 12 (2.4) | 143 (81.3) | 30 (7.6) | 6 (0.4) | 26 (2.9) | 297 (15.7) |
| Parity | |||||||||||
| Nulliparous | 527 (44.8) | 81 (57.0) | 663 (30.0) | 782 (41.2) | 621 (41.3) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 662 (48.5) | 516 (58.3) | 617 (32.6) |
| 1–2 | 495 (42.1) | 57 (40.1) | 1295 (58.7) | 902 (47.5) | 691 (46.0) | 0 (0.0) | 26 (14.8) | 219 (55.2) | 645 (47.2) | 304 (34.4) | 1094 (57.9) |
| ≥ 3 | 0 (0.0) | 4 (2.8) | 245 (11.1) | 115 (6.1) | 191 (12.7) | 0 (0.0) | 141 (80.1) | 53 (13.4) | 59 (4.3) | 65 (7.3) | 180 (9.5) |
| Missing | 155 (13.2) | 0 (0.0) | 5 (0.2) | 101 (5.3) | 0 (0.0) | 510 (100.0) | 9 (5.1) | 125 (31.5) | 0 (0.0) | 0 (0.0) | 0 (0.0) |
| Time of initiation for maternal prenatal health care access | |||||||||||
| 1st trimester | – | – | 2174 (98.5) | 1712 (90.1) | – | – | 133 (75.6) | 116 (29.2) | 1366 (100.0) | – | 0 (0.0) |
| 2nd trimester | – | – | 30 (1.4) | 163 (8.6) | – | – | 29 (16.5) | 16 (4.0) | 0 (0.0) | – | 1891 (100.0) |
| 3rd trimester | – | – | 4 (0.2) | 19 (1.0) | – | – | 2 (1.1) | 3 (0.8) | 0 (0.0) | – | 0 (0.0) |
| No access | – | – | 0 (0.0) | 1 (0.1) | – | – | 6 (3.4) | 0 (0.0) | 0 (0.0) | – | 0 (0.0) |
| Missing | 1177 (100.0) | 142 (100.0) | 0 (0.0) | 5 (0.3) | 1503 (100.0) | 510 (100.0) | 6 (3.4) | 262 (66.0) | 0 (0.0) | 885 (100.0) | 0 (0.0) |
| Maternal prenatal smoking (yes) | 190 (16.1) | 9 (6.3) | 97 (4.4) | 186 (9.8) | 151 (10.0) | 67 (13.1) | 57 (32.4) | 22 (5.5) | 132 (9.7) | 220 (24.9) | 238 (12.6) |
| Missing | 0 (0.0) | 0 (0.0) | 183 (8.3) | 224 (11.8) | 1 (0.1) | 2 (0.4) | 1 (0.6) | 3 (0.8) | 7 (0.5) | 18 (2.0) | 0 (0.0) |
| Maternal BMI (kg/m2), mean (SD) | 25.7 (6.2) | 23.9 (5.8) | 27.6 (6.5) | 26.1 (6.2) | 27.5 (7.5) | 28.3 (7.6) | 29.0 (10.3) | 27.3 (6.9) | 24.7 (5.2) | 26.6 (7.1) | 25.8 (5.5) |
| Missing | 0 | 100 | 23 | 71 | 5 | 14 | 4 | 127 | 8 | 32 | 60 |
| Maternal diabetes | 50 (4.2) | 0 (0.0) | 273 (12.4) | 183 (9.6) | 80 (5.3) | 0 (0.0) | 8 (4.5) | 54 (13.6) | 78 (5.7) | 841 (95.0) | 233 (12.3) |
| Missing | 0 (0.0) | 142 (100.0) | 8 (0.4) | 71 (3.7) | 60 (4.0) | 510 (100.0) | 7 (4.0) | 114 (28.7) | 9 (0.7) | 44 (5.0) | 0 (0.0) |
| Maternal high blood pressure | 139 (11.8) | 0 (0.0) | 275 (12.5) | 195 (10.3) | 141 (9.4) | 97 (19.0) | 20 (11.4) | 37 (9.3) | 158 (11.6) | 861 (97.3) | 210 (11.1) |
| Missing | 33 (2.8) | 142 (100.0) | 0 (0.0) | 1705 (89.7) | 73 (4.9) | 413 (81.0) | 6 (3.4) | 360 (90.7) | 33 (2.4) | 24 (2.7) | 1681 (88.9) |
| Maternal history of any psychiatric disorders | 204 (17.3) | 0 (0.0) | 1203 (54.5) | 871 (45.8) | 31 (2.1) | 210 (41.2) | 119 (67.6) | 38 (9.6) | 140 (10.2) | 0 (0.0) | 216 (11.4) |
| Missing | 29 (2.5) | 142 (100.0) | 0 (0.0) | 561 (29.5) | 293 (19.5) | 0 (0.0) | 0 (0.0) | 271 (68.3) | 207 (15.2) | 885 (100.0) | 0 (0.0) |
| Maternal alcohol use | 76 (6.5) | 2 (1.4) | 273 (12.4) | 391 (20.6) | 121 (8.1) | 13 (2.5) | 19 (10.8) | 31 (7.8) | 859 (62.9) | 0 (0.0) | 51 (2.7) |
| Missing | 0 (0.0) | 1 (0.7) | 257 (11.6) | 245 (12.9) | 1 (0.1) | 1 (0.2) | 5 (2.8) | 277 (69.8) | 86 (6.3) | 885 (100.0) | 34 (1.8) |
| Maternal folic acid supplementation | 471 (40.0) | 0 (0.0) | 1107 (50.1) | 206 (10.8) | 1239 (82.4) | 0 (0.0) | 0 (0.0) | 30 (7.6) | 155 (11.3) | 0 (0.0) | 0 (0.0) |
| Missing | 0 (0.0) | 142 (100.0) | 1056 (47.8) | 235 (12.4) | 181 (12.0) | 510 (100.0) | 176 (100.0) | 122 (30.7) | 20 (1.5) | 885 (100.0) | 1891 (100.0) |
| Maternal other vitamin and mineral supplements | 1174 (99.7) | 0 (0.0) | 1107 (50.1) | 1525 (80.3) | 1392 (92.6) | 0 (0.0) | 0 (0.0) | 259 (65.2) | 1301 (95.2) | 0 (0.0) | 1827 (96.6) |
| Missing | 0 (0.0) | 142 (100.0) | 1056 (47.8) | 249 (13.1) | 33 (2.2) | 510 (100.0) | 176 (100.0) | 125 (31.5) | 53 (3.9) | 885 (100.0) | 0 (0.0) |
Note: Data shown are n (%) except where indicated.
Abbreviations: ADI‐R, autism diagnostic interview‐revised; ADOS, autism diagnostic observation schedule.
a
Cohort 4 utilized both ADI‐R and ADOS to obtain ASD diagnosis.