Table 1.
Study population
| Study group | Control group | |
|---|---|---|
| Overall collectivea | 322 | 464 |
| Sexa | ||
| Male | 194 (60.2) | 287 (61.9) |
| Female | 128 (39.8) | 177 (38.1) |
| Age (mo)b | ||
| Minimum | 0 | 0 |
| Maximum | 198 | 203 |
| Mean ± SD | 26.4 ± 34.9 | 31.8 ± 43.0 |
| Median | 15.0 | 16.0 |
| 25%‐percentile | 4.0 | 4.0 |
| 75%‐percentile | 33.2 | 37.0 |
| Admission reasonsa | ||
| 1 | 257 (79.8) | 363 (78.2) |
| ≥2 | 65 (20.2) | 101 (21.8) |
| Lower respiratory tract infection | 199 (61.8) | 276 (59.5) |
| Upper respiratory tract infection | 97 (30.1) | 157 (33.4) |
| Nonrespiratory tract infection | 48 (14.9) | 43 (9.3) |
| Seizure | 29 (9.0) | 61 (13.1) |
| Influenza | 19 (5.9) | 44 (9.5) |
| Past medical historya | 98 (30.4) | 138 (29.7) |
a
Binary variables: absolute and relative number.
b
Continuous variables: median, minimum, maximum, mean ± standard deviation (SD).