Table 1.
Infant and Maternal Characteristics of JIA Cases and non-JIA Controls born in Washington State 1997–2010
| Characteristics | Cases (N = 1,252)a |
Controls (N = 6,072)a |
||
|---|---|---|---|---|
| n | % | n | % | |
| Infant Factors | ||||
| Female | 843 | 67.3 | 2,903 | 47.8 |
| Twin/multiple gestationb | 18 | 1.4 | 79 | 1.3 |
| Race/Ethnicity | ||||
| White | 984 | 81.3 | 4,425 | 74.8 |
| Black | 37 | 3.1 | 316 | 5.3 |
| Asian/Pacific Islander | 60 | 4.9 | 426 | 7.2 |
| Native American | 38 | 3.1 | 150 | 2.5 |
| Hispanic | 91 | 7.5 | 598 | 10.1 |
| Other | 1 | 0.1 | 3 | 0.1 |
| Maternal Factors | ||||
| Age (years) | ||||
| < 20 | 106 | 8.5 | 694 | 11.4 |
| 20–24 | 233 | 18.6 | 1,536 | 25.3 |
| 25–29 | 385 | 30.8 | 1,774 | 29.2 |
| 30–34 | 341 | 27.2 | 1,326 | 21.9 |
| 35+ | 187 | 14.9 | 739 | 12.2 |
| Education (years) | ||||
| < 12 | 100 | 12.9 | 639 | 18.0 |
| 12 | 227 | 29.3 | 1,092 | 30.8 |
| 12–16 | 188 | 24.2 | 927 | 26.1 |
| 16+ | 261 | 33.6 | 888 | 25.0 |
| Unmarried | 250 | 20.0 | 1,577 | 26.1 |
| Trimester of inception of prenatal care | ||||
| First | 987 | 85.9 | 4,591 | 81.1 |
| Second | 133 | 11.6 | 897 | 15.8 |
| Third | 29 | 2.5 | 175 | 3.1 |
| Medicaid insurance | 282 | 26.3 | 1,789 | 37.0 |
aNumbers may not add up to totals due to missing data
bOR for association with JIA = 1.04, 95% CI: 0.62–1.74