Table 1.
Demographic characteristics and potentialconfounders by parent report of doctor-diagnosed asthma.
| Without asthma (n = 1,934) | With asthma (n = 209) | |||
|---|---|---|---|---|
| Characteristic | Mean ± SD or % | Mean ± SD or % | ||
| FeNO (ppb)a | 13.1 (1.8) | 16.2 (2.1) | ||
| Age (years) | 9.3 ± 0.6 | 9.3 ± 0.6 | ||
| Percent male | 47.1 | 55.5 | ||
| Body mass index percentile | 66.0 ± 29.2 | 69.7 ± 28.7 | ||
| Percent missing | 0.6 | 0.5 | ||
| Race/ethnicity (%) | ||||
| White/non-Hispanic | 33.7 | 32.1 | ||
| Hispanic | 56.8 | 55.0 | ||
| Black | 1.8 | 2.9 | ||
| Asian/Hawaiian/Pacific Islander | 3.1 | 3.3 | ||
| Other | 4.6 | 6.7 | ||
| Missing | 0.1 | 0.0 | ||
| Parent education (%) | ||||
| < 12th grade | 20.4 | 15.3 | ||
| Completed 12th grade | 17.1 | 16.7 | ||
| > 12th grade | 58.0 | 64.6 | ||
| Missing | 4.5 | 3.3 | ||
| Respiratory allergy (%) | ||||
| Never | 47.6 | 17.7 | ||
| No current | 28.3 | 29.7 | ||
| Current | 24.0 | 52.6 | ||
| Missing | 0.1 | 0.0 | ||
| Asthma medication (%) | ||||
| None | 97.4 | 62.7 | ||
| Rescue only | 2.2 | 28.2 | ||
| Control only | 0.2 | 3.3 | ||
| Rescue and control | 0.2 | 5.7 | ||
| Exposed to secondhand smoke (%) | 5.1 | 3.8 | ||
| Missing | 0.6 | 1.4 | ||
| Time of FeNO collection [hours (%)] | ||||
| 0800–0859 | 6.3 | 5.3 | ||
| 0900–1159 | 85.7 | 81.8 | ||
| 1200–1359 | 7.4 | 12.0 | ||
| 1400–1559 | 0.7 | 1.0 | ||
| Percent outdoor test | 3.2 | 2.4 | ||
| aGeometric mean (SD). | ||||