Table 1.
Subject Demographics
| Characteristic | Total (n = 106) | Mild (n = 42) | Severe (n = 64) | Mild vs Severe | Correlation With GRSS | ||
|---|---|---|---|---|---|---|---|
| t Statistics | P Value | Pearson Correlation Coefficient | P Value | ||||
| Continuous variable, mean ± SD |
|||||||
| Age, mo | 3.35 ± 2.22 | 3.52 ± 1.99 | 3.24 ± 2.37 | 0.6579 | .5122 | −0.2081 | .0323 |
| Gestational age, wk | 38.90 ± 1.37 | 39.05 ± 1.25 | 38.8 ± 1.44 | 0.9515 | .3437 | −0.1003 | .3064 |
| Birth weight, kg | 3.34 ± 0.61 | 3.32 ± 0.68 | 3.36 ± 0.57 | −0.3240 | .7468 | 0.0721 | .4625 |
| Family size | 4.16 ± 2.25 | 4.43 ± 2.86 | 3.98 ± 1.73 | 0.9027 | .3703 | −0.0494 | .6150 |
| Viral load, log10 NS titer | 2.43 ± 1.16 | 2.48 ± 1.11 | 2.40 ± 1.20 | 0.3191 | .7504 | 0.0209 | .8346 |
| Mild vs Severe | Comparison With GRSS | ||||||
| Fisher Odds Ratio | P Value | t Statistics | P Value | ||||
| Categorical variable, No. (%) | |||||||
| Sex, female | 54 (51) | 19 (45) | 35 (55) | 0.687 | .4275 | 0.5493 | .584 |
| White | 62 (58) | 23 (55) | 39 (61) | 1.5276 | .3115 | −0.5511 | .5832 |
| Tobacco smoke exposure, true | 36 (34) | 14 (33) | 22 (34) | 1.0472 | 1 | −0.7605 | .4492 |
| RSV strain, A | 59 (56) | 23 (55) | 36 (56) | 0.9939 | 1 | 0.207 | .8365 |
| Bacterial colonization, true | 79 (75) | 30 (71) | 49 (77) | 1.3033 | .6498 | −1.2747 | .2092 |
| Viral coinfection, truea | 18 (17) | 9 (21) | 9 (14) | 0.603 | .4285 | 0.6068 | .5495 |
Data represent samples collected at the time of acute infection (1–10 d after onset of clinical symptoms) from 106 subjects. Data are mean ± SE for continuous variables and the frequency in both groups for categorical variables. P values were computed by statistical tests that are appropriate to the nature of the variables (see section “Statistical Analysis of Clinical Data”).
Abbreviations: GRSS, global respiratory severity score; NS, neutralization serum; RSV, respiratory syncytial virus.
aCoinfecting viruses were adenovirus (3), bocavirus (1), coronaviruses (11), human metapneumovirus (1), parechovirus (1), and rhinovirus (6).