Table 3.
Descriptive Characteristics of the Medical and Environmental Variables
| Na | Mean | (SD) | Percent | |
|---|---|---|---|---|
| Allergies: 2 months | 96 | 3.1% | ||
| 6 months | 97 | 7.2% | ||
| 9 months | 88 | 14.8% | ||
| 13 months | 86 | 8.1% | ||
| 18 months | 91 | 14.3% | ||
| 22 months | 83 | 14.5% | ||
| 27 months | 55 | 21.8% | ||
| Upper respiratory tract infections: 2 months | 98 | 36.7% | ||
| 6 months | 98 | 78.6% | ||
| 9 months | 90 | 64.4% | ||
| 13 months | 88 | 77.3% | ||
| 18 months | 94 | 83.0% | ||
| 22 months | 81 | 80.3% | ||
| 27 months | 57 | 86.0% | ||
| Pneumonia in first 13 months | 111 | 9.9% | ||
| Weight for Length2: Early Ages | 107 | 1.7 | (0.2) | |
| Later Ages | 72 | 1.6 | (0.2) | |
| Cesarean Delivery | 113 | 54.0% | ||
| HOME Sub-Scale I | 109 | 10.0 | (0.9) | |
| Home Sub-Scale II | 109 | 6.5 | (1.3) |
a
The N varies over time because of missing contacts, study withdrawals, and incomplete questionnaires.