Table 3. Factors predicting time to SA colonization of the nasopharynx from age one month onwards (n=1765 cultures from 367 infants).
| Univariate analysis | Multivariate analysis | |||
|---|---|---|---|---|
|
| ||||
| Factor | Coefficient (95% CI) | P value | Effect | P value |
|
| ||||
| Gender | -0.13 (-0.44, 0.17) | 0.39 | -0.13 | 0.38 |
|
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| Race/ethnicity | 0.09 | 0.13 | ||
| White* | 0.028 (-0.31, 0.47) | Comparator | ||
| Hispanic | 0.24 (-0.064, 0.54) | 0.14 (-0.22, 0.49) | ||
| Black | -0.45 (-0.84, 0.065) | -0.37 (-0.84, 0.10) | ||
| Asian | 0.39 (-1.09, 1.87) | 0.38 (-1.10, 1.86) | ||
|
| ||||
| Breastfeeding | -0.11 (-0.42, 0.19) | 0.46 | -0.24 (-0.55, 0.065) | 0.12 |
|
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| Cigarette smoke exposure | 0.0024 (-0.36, 0.36) | 0.99 | 0.027 (-0.34, 0.40) | 0.89 |
|
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| Daycare attendance | -0.30 (-0.79, 0.18) | 0.22 | -0.075 (-0.24, -0.024) | 0.015 |
|
| ||||
| NTHI Colonization | -0.74 (-1.25, 0.23) | 0.004 | -0.60 (-1.12, -0.085) | 0.023 |
|
| ||||
| MC colonization | -0.53 (-0.84, -0.21) | 0.001 | -0.45 (-0.44, -0.12) | 0.007 |
|
| ||||
| SP colonization | -0.33 (-0.78, -0.04) | 0.009 | -0.071 (-0.48, 0.34) | 0.74 |
*
Non-Hispanic white
Above statistical analysis used Cox proportionate hazards model. This model took into account a child with multiple positive SA samples. All of the factors were present prior to the positivity of SA colonization. NS = not significant; SA = S. aureus, SP = S. pneumoniae, NTHI = non-typeable H. influenzae, MC = M. catarrhalis; CI = confidence interval.