TABLE 1

Characteristics of the Cohort, Their Mothers, and Their Health Care Providers According to Influenza Immunization Status (N = 762 977)

CharacteristicnInfluenza Vaccination Status
Fully Vaccinated (n = 48 511)Partially Vaccinated (n = 58 144)Not Vaccinated (n = 656 322)
Normal birth wt without chronic conditions706 47343 774 (6.2%)52 968 (7.5%)609 731 (86.3%)
Normal birth wt with chronic conditions11 4921026 (8.9%)1239 (10.8%)9227 (80.3%)
Low birth wt45 0123711 (8.2%)3937 (8.7%)37 364 (83.0%)
Gender
 Female371 17123 426 (6.3%)27 939 (7.5%)319 806 (86.2%)
 Male391 80625 085 (6.4%)30 205 (7.7%)336 516 (85.9%)
Age at FEW
 6–8 mo203 66811 134 (5.5%)11 743 (5.8%)180 791 (88.8%)
 9–11 mo176 92212 850 (7.3%)14 297 (8.1%)149 775 (84.7%)
 ≥12 mo382 38724 527 (6.4%)32 104 (8.4%)325 756 (85.2%)
No. of primary care visits 1 year after birth
 3–6 visits142 2053294 (2.3%)5938 (4.2%)132 973 (93.5%)
 7–11 visits360 65520 613 (5.7%)25 415 (7.0%)314 627 (87.2%)
 ≥12 visits260 11724 604 (9.5%)26 791 (10.3%)208 722 (80.2%)
PCP
 FP: low volume271 23513 839 (5.1%)18 002 (6.6%)239 394 (88.3%)
 FP: high volume280 82514 827 (5.3%)20 580 (7.3%)245 418 (87.4%)
 Pediatrician210 91719 845 (9.4%)19 562 (9.3%)171 510 (81.3%)
Continuity of care
 Very low (<50%)66 7203381 (5.1%)5153 (7.7%)58 186 (87.2%)
 Low (50%–67%)114 5506225 (5.4%)8683 (7.6%)99 642 (87.0%)
 Medium (67%–86%)198 96112 912 (6.5%)15 662 (7.9%)170 387 (85.6%)
 High (86%–100%)382 74625 993 (6.8%)28 646 (7.5%)328 107 (85.7%)
Neighborhood income quintilea
 Quintile 1 (lowest)166 6188699 (5.2%)12 798 (7.7%)145 121 (87.1%)
 Quintile 2151 1718852 (5.9%)10 971 (7.3%)131 348 (86.9%)
 Quintile 3156 1349792 (6.3%)11 408 (7.3%)134 934 (86.4%)
 Quintile 4159 29711 141 (7.0%)11 931 (7.5%)136 225 (85.5%)
 Quintile 5 (highest)129 75710 027 (7.7%)11 036 (8.5%)108 694 (83.8%)
Rural residence
 No689 92745 271 (6.6%)54 050 (7.8%)590 606 (85.6%)
 Yes73 0503240 (4.4%)4094 (5.6%)65 716 (90.0%)
Mom vaccinated for influenza in year after delivery
 No651 19828 013 (4.3%)35 968 (5.5%)587 217 (90.2%)
 Yes111 77920 498 (18.3%)22 176 (19.8%)69 105 (61.8%)
Mom aged <20 y at first childbirth
 No695 43946 184 (6.6%)54 088 (7.8%)595 167 (85.6%)
 Yes67 5382327 (3.4%)4056 (6.0%)61 155 (90.5%)
  • a Income level of quintiles varies because income quintiles are adjusted for household and community size.