Table 1 Infant and maternal characteristics of JIA cases and non-JIA controls
From: Association of juvenile idiopathic arthritis with maternal infection: a case control study
Characteristics | Cases (N = 1290) | Controls (N = 6072) |
|---|---|---|
n(%) | n(%) | |
Infant | ||
Female | 871 (68) | 2903 (48) |
Birthweight (grams) | ||
< 2500 | 73 (6) | 339 (6) |
2500–3999 | 1067 (83) | 4912 (81) |
4000 + | 148 (11) | 803 (13) |
Missing | 2 (0.2) | 18 (0.3) |
Gestational age (weeks) | ||
< 37 | 82(7) | 389 (7) |
37–42 | 1071 (85) | 4943 (83) |
> 42 | 104 (8) | 588 (10) |
Missing | 33 (3) | 152 (3) |
Number of older siblings | ||
None | 541 (43) | 2517 (42) |
1 | 442 (35) | 1942 (33) |
2 + | 276 (22) | 1474 (25) |
Missing | 31 (2) | 139 (2) |
Mother | ||
Age (years) | ||
< 20 | 108 (8) | 694 (11) |
20–34 | 991 (77) | 4636 (76) |
≥35 | 191 (15) | 739 (12) |
Missing | 0 | 3 (0.05) |
Race/Ethnicity | ||
White | 1039 (84) | 4638 (78) |
Black | 24 (2) | 233 (4) |
Native American | 37 (3) | 123 (2) |
Asian/Pacific Islander | 59 (5) | 402 (7) |
Hispanic | 79 (6) | 526 (9) |
Missing | 52 (4) | 150 (2) |
Education (years) | ||
< 13 | 329 (42) | 1731 (49) |
13 to 15 | 189 (24) | 927 (26) |
≥16 | 265 (34) | 888 (25) |
Missing | 507 (39) | 2526 (42) |
Married | 1032 (80) | 4469 (74) |
Missing | 2 (0.2) | 26 (0.4) |
Trimester prenatal care began | ||
1st | 1017 (86) | 4591 (81) |
2nd | 138 (12) | 897 (16) |
3rd | 31 (3) | 175 (3) |
Missing | 104 (8) | 409 (7) |
Cesarean section | 277 (22) | 1151 (19) |
Missing | 1 (0.1) | 5 (0.1) |
Other | ||
Medicaid or Medicare billed for labor and delivery | 284 (26) | 1789 (37) |
Missing | 195 (15) | 1240 (20) |
Residence | ||
Urban | 820 (76) | 3787 (77) |
Rural | 252 (24) | 1127 (23) |
Missing | 218 (17) | 1158 (19) |