| No asthma | Lifetime asthma | p Value‡ | |||
| N† | (%) | N† | (%) | ||
| Sex | |||||
| Girls | 1454 | (54.9) | 211 | (44.3) | <0.001 |
| Boys | 1194 | (45.1) | 265 | (55.7) | |
| Age (years) | |||||
| ⩽10 | 1458 | (55.1) | 255 | (53.6) | 0.37 |
| 11–12 | 512 | (19.3) | 85 | (17.9) | |
| >12 | 678 | (25.6) | 136 | (28.5) | |
| Ethnicity | |||||
| Non-Hispanic white | 1823 | (68.8) | 338 | (71.0) | 0.35 |
| Hispanic white | 825 | (31.2) | 138 | (29.0) | |
| Parental history of asthma | |||||
| No | 2075 | (83.1) | 265 | (58.6) | <0.001 |
| Yes | 422 | (16.9) | 187 | (41.4) | |
| Child’s atopic status§ | |||||
| No | 1687 | (68.3) | 131 | (31.2) | <0.001 |
| Yes | 782 | (31.7) | 289 | (68.8) | |
| In utero exposure to maternal smoking | |||||
| No | 2149 | (83.0) | 380 | (80.7) | 0.23 |
| Yes | 441 | (17.0) | 91 | (19.3) | |
| Number of smokers at home | |||||
| 0 | 1819 | (71.0) | 313 | (67.7) | 0.26 |
| 1 | 502 | (19.6) | 96 | (20.8) | |
| ⩾2 | 240 | (9.4) | 53 | (11.5) | |
| Annual family income ($) | |||||
| <15000 | 317 | (13.9) | 49 | (11.7) | 0.15 |
| 15000–49999 | 969 | (42.5) | 167 | (39.9) | |
| ⩾50000 | 994 | (43.6) | 207 | (48.4) | |
| Parent/guardian education | |||||
| <12th grade | 320 | (12.4) | 33 | (7.0) | 0.005 |
| 12th grade | 494 | (19.2) | 95 | (20.2) | |
| Some college | 1160 | (45.0) | 242 | (51.5) | |
| College | 268 | (10.4) | 46 | (9.8) | |
| Some graduate | 336 | (13.0) | 54 | (11.5) | |
| Health insurance coverage | |||||
| No | 400 | (15.3) | 37 | (7.9) | <0.001 |
| Yes | 2208 | (84.7) | 430 | (92.1) | |
*Participants include non-Hispanic and Hispanic white children of the Children’s Health Study with and without asthma with available EPHX1 Tyr113His and His139Arg genotypes obtained from buccal samples collected during 1998–2006.
†Totals differ due to missing data.
‡p values from Pearson χ2 tests comparing children with asthma with those without asthma.
§Child’s atopic status was determined based on parental report of allergy and hay fever.