Selected newborn and maternal characteristics of healthy full term infants with a hospitalization in the first 90 days and comparison infants, Washington State 1989–1996
| Early hospitalization (n=29 466) | No early hospitalization (n=29 750) | ||||
|---|---|---|---|---|---|
| No | Injury rate* | No | Injury rate* | Stratum specific RR (95% CI) | |
| Columns may not add up to total No because of missing data. | |||||
| *Cumulative injury rate/10 000 children ages 3–24 months. | |||||
| †Estimate of common relative risk (Mantel-Haenszel). | |||||
| ‡Maternal education was available on the birth certificate beginning in 1992. From 1992–95 11% of the data were missing. | |||||
| All children | 29 466 | 76 | 29 750 | 47 | 1.6 (1.3 to 2.0) |
| Infant gender | 1.6 (1.3 to 2.0)† | ||||
| Male | 16 821 | 84 | 15 098 | 52 | 1.6 (1.2 to 2.1) |
| Female | 12 645 | 70 | 14 652 | 43 | 1.6 (1.2 to 2.3) |
| Birth weight (g) | 1.6 (1.3 to 2.0)† | ||||
| 2000–2499 | 996 | 80 | 559 | 54 | 1.5 (0.4 to 5.6) |
| 2500–4000 | 24 708 | 78 | 24 768 | 50 | 1.5 (1.2 to 1.9) |
| >4000 | 3 752 | 77 | 4 414 | 32 | 2.4 (1.3 to 4.6) |
| Any malformation at birth | 2 202 | 77 | 1 383 | 72 | 1.1 (0.5 to 2.3) |
| Maternal characteristics | |||||
| Age (years) | 1.5 (1.2 to 1.9)† | ||||
| <20 | 4 192 | 112 | 3 039 | 79 | 1.4 (0.9 to 2.3) |
| 20–24 | 8 411 | 101 | 7 492 | 63 | 1.6 (1.1 to 2.3) |
| 25–34 | 14 212 | 60 | 16 113 | 39 | 1.5 (1.1 to 2.1) |
| 35+ | 2 633 | 30 | 3 084 | 23 | 1.3 (0.5 to 3.7) |
| Race | 1.6 (1.3 to 2.0)† | ||||
| White, non-Hispanic | 22 916 | 76 | 23 683 | 46 | 1.6 (1.3 to 2.1) |
| White, Hispanic | 2 678 | 49 | 2 150 | 42 | 1.2 (0.5 to 2.7) |
| African American | 902 | 122 | 1 027 | 58 | 2.1 (0.8 to 5.6) |
| Marital status | 1.6 (1.3 to 2.0)† | ||||
| Not married | 8 659 | 98 | 6 890 | 58 | 1.7 (1.2 to 2.5) |
| Married | 20 763 | 70 | 22 821 | 45 | 1.6 (1.2 to 2.0) |
| Education‡ | 1.5 (1.0 to 2.1)† | ||||
| Less than high school | 1 768 | 79 | 1 295 | 61 | 1.3 (0.7 to 2.5) |
| High school | 3 683 | 69 | 3 824 | 56 | 1.2 (0.7 to 2.1) |
| > High school | 4 569 | 45 | 5 689 | 20 | 2.3 (1.1 to 4.6) |
| Employment | 1.7 (1.4 to 2.1)† | ||||
| Teen | 1 320 | 129 | 937 | 75 | 2.3 (1.1 to 4.6) |
| Unemployed | 11 751 | 90 | 11 313 | 55 | 1.6 (1.2 to 2.2) |
| Employed | 13 496 | 62 | 14 944 | 36 | 1.7 (1.2 to 2.4) |
| Source of insurance | 1.5 (1.2 to 1.9)† | ||||
| Medicaid | 11 268 | 93 | 8 293 | 58 | 1.6 (1.1 to 2.3) |
| Other | 16 406 | 69 | 18 336 | 46 | 1.5 (1.1 to 2.0) |
| County of residence | 1.6 (1.3 to 2.0)† | ||||
| Rural | 3 799 | 97 | 3 543 | 54 | 1.8 (1.0 to 3.2) |
| Suburban/small urban | 8 451 | 64 | 7 128 | 52 | 1.2 (0.8 to 1.9) |
| Metropolitan | 16 948 | 78 | 18 748 | 45 | 1.7 (1.3 to 2.3) |
| No of prior deliveries | 1.6 (1.3 to 2.0)† | ||||
| 2+ | 7 996 | 96 | 7 694 | 55 | 1.8 (1.2 to 2.6) |
| 1 | 9 522 | 83 | 9 755 | 48 | 1.7 (1.2 to 2.5) |
| 0 | 11 579 | 60 | 11 975 | 42 | 1.4 (1.0 to 2.1) |
| Month prenatal care began | 1.6 (1.3 to 2.0)† | ||||
| 7–10 | 1 095 | 146 | 913 | 33 | 4.4 (1.3 to 15.2) |
| 4–6 | 4 934 | 99 | 4 681 | 62 | 1.6 (1.0 to 2.5) |
| 0–3 | 22 055 | 67 | 22 874 | 45 | 1.5 (1.2 to 1.9) |