Table 1.
Distribution of Sample Characteristics by Mother’s Report of Cell Phone Exposure
| No Exposure (n = 21,507) | Prenatal Exposure Onlya (n = 10,690) | Postnatal Exposure Onlyb (n = 8,213) | Both Prenatal and Postnatal Exposurea,b (n = 9,781) | Unknown Exposure (n = 2,489) | Total (n = 52,680) | |||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
| ||||||||||||
| n | % | n | % | n | % | n | % | n | % | n | % | |
|
| ||||||||||||
| Sex of child | ||||||||||||
| Boy | 11,431 | 53.2 | 5,821 | 54.5 | 3,799 | 46.3 | 4,596 | 47.0 | 1,341 | 53.9 | 26,988 | 51.2 |
| Girl | 10,076 | 46.8 | 4,869 | 45.5 | 4,414 | 53.7 | 5,185 | 53.0 | 1,148 | 46.1 | 25,692 | 48.8 |
|
| ||||||||||||
| Social-occupational status | ||||||||||||
| High | 14,915 | 69.3 | 7,161 | 67.0 | 5,390 | 65.6 | 5,815 | 59.5 | 1,549 | 62.2 | 34,830 | 66.1 |
| Medium | 5,219 | 24.3 | 2,700 | 25.3 | 2,217 | 27.0 | 2,942 | 30.1 | 737 | 29.6 | 13,815 | 26.2 |
| Low | 487 | 2.3 | 343 | 3.2 | 251 | 3.1 | 503 | 5.1 | 95 | 3.8 | 1,679 | 3.2 |
| Missing | 886 | 4.1 | 486 | 4.5 | 355 | 4.3 | 521 | 5.3 | 108 | 4.3 | 2,356 | 4.5 |
|
| ||||||||||||
| Child exposed to tobacco smoke in home | ||||||||||||
| Often or daily | 1,513 | 7.0 | 876 | 8.2 | 830 | 10.1 | 1,241 | 12.7 | 204 | 8.2 | 4,664 | 8.9 |
| Rarely | 5,054 | 23.5 | 2,135 | 20.0 | 2,188 | 26.6 | 2,361 | 24.1 | 590 | 23.7 | 12,328 | 23.4 |
| Never | 14,899 | 69.3 | 7,658 | 71.6 | 5,182 | 63.1 | 6,155 | 62.9 | 1,528 | 61.4 | 35,422 | 67.2 |
| Missing | 41 | 0.2 | 21 | 0.2 | 13 | 0.2 | 24 | 0.3 | 167 | 6.7 | 266 | 0.5 |
|
| ||||||||||||
| Mother’s age at birth of child | ||||||||||||
| 25 years or younger | 1,475 | 6.9 | 1,258 | 11.8 | 759 | 9.2 | 1,752 | 17.9 | 271 | 10.9 | 5,515 | 10.5 |
| 26–30 years | 8,594 | 40.0 | 4,414 | 41.3 | 3,440 | 41.9 | 4,053 | 41.4 | 997 | 40.1 | 21,498 | 40.8 |
| 31–35 years | 8,324 | 38.7 | 3,697 | 34.6 | 2,952 | 35.9 | 2,924 | 29.9 | 882 | 35.4 | 18,779 | 35.6 |
| Older than 35 years | 3,114 | 14.5 | 1,321 | 12.4 | 1,062 | 12.9 | 1,052 | 10.8 | 339 | 13.6 | 6,888 | 13.1 |
| Mean (SD) | 31.1 (4.0) | 30.4 (4.3) | 30.7 (4.1) | 29.6 (4.6) | 30.7 (4.4) | 30.6 (4.3) | ||||||
|
| ||||||||||||
| Mother diagnosed with migraine (hospital register) | ||||||||||||
| Yes | 330 | 1.5 | 235 | 2.2 | 169 | 2.1 | 220 | 2.2 | 37 | 1.5 | 991 | 1.9 |
| No | 21,177 | 98.5 | 10,455 | 97.8 | 8,044 | 97.9 | 9,561 | 97.8 | 2,452 | 98.5 | 51,689 | 98.1 |
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| Mother’s feelings of stress, worry, or burden during pregnancy (0–54) | ||||||||||||
| Mean (SD) | 22.3 (3.6) | 22.4 (3.7) | 22.6 (3.9) | 23.0 (4.14) | 22.9 (4.0) | 22.5 (3.8) | ||||||
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| Child gets migraines (mother’s report) | ||||||||||||
| Yes | 176 | 0.8 | 116 | 1.1 | 89 | 1.1 | 120 | 1.2 | 22 | 0.9 | 523 | 1.0 |
| No | 20,993 | 97.6 | 10,398 | 97.3 | 7,989 | 97.3 | 9,472 | 96.8 | 2,349 | 94.4 | 51,201 | 97.2 |
| Missing | 338 | 1.6 | 176 | 1.6 | 135 | 1.6 | 189 | 1.9 | 118 | 4.7 | 956 | 1.8 |
|
| ||||||||||||
| Child has headache-related symptoms (mother’s report) | ||||||||||||
| Yes | 3,544 | 16.5 | 2,030 | 19 | 1,737 | 21.1 | 2,242 | 22.9 | 490 | 19.7 | 10,043 | 19.1 |
| No | 17,928 | 83.4 | 8,645 | 80.9 | 6,455 | 78.6 | 7,513 | 76.8 | 1,843 | 74 | 42,384 | 80.5 |
| Missing | 35 | 0.2 | 15 | 0.1 | 21 | 0.3 | 26 | 0.3 | 156 | 6.3 | 253 | 0.5 |
a
Mother reported using cell phone while pregnant.
b
Mother reported child uses cell phone at age seven years.