Table 3.
Characteristics of cohort participants who completed at least one surveillance report and among these surveillance participants, the percentage of weekly reports completed
| Cohort Enrollees (Year 1) | Completed One or More Surveillance Reports | Among Surveillance Participants, Percentage (95% CI) of Weeks with Completed Reports a | |||
|---|---|---|---|---|---|
| N (Col. %) | N (Row %) | p-value b | p-value c | ||
| Total N | 1374 (100) | 1106 (80) | 55 (53–56) | ||
| Medical Record Variables | |||||
| Study Site | p < .0005 | p < .0005 | |||
| Site 1 | 565 (41) | 503 (89) | 63 (61–65) | ||
| Site 2 | 809 (59) | 603 (75) | 47 (46–49) | ||
| Race (White) | p < .0005 | p < .0005 | |||
| White | 934 (68) | 785 (84) | 57 (56–59) | ||
| Non-White | 440 (32) | 321 (73) | 48 (45–50) | ||
| Ethnicity | p < .0005 | p < .0005 | |||
| Hispanic/Latina | 173 (13) | 122 (71) | 48 (44–52) | ||
| Non-Hispanic | 1201 (87) | 984 (82) | 55 (54–57) | ||
| High Risk Medical Conditions | |||||
| Chronic Condition (prior to pregnancy) | 277 (20) | 228 (82) | p = .39 | 57 (54–60) | p = .08 |
| No condition | 1097 (80) | 878 (80) | 54 (52–56) | ||
| Pregnancy Complication | 1034 (75) | 830 (80) | p = .72 | 54 (53–56) | p = .50 |
| No complication | 340 (25) | 276 (81) | 55 (53–58) | ||
| Medical visits for ARI (1 or more) | |||||
| Year Prior to Study (12 months) | 320 (23) | 255 (80) | p = .68 | 55 (53–56) | p = .69 |
| No visit | 1054 (77) | 851 (81) | 55 (53–56) | ||
| Study Period (6 months) | 307 (22) | 234 (76) | p = .03 | 55 (53–56) | p = .76 |
| No visit | 1067 (78) | 872 (82) | 55 (53–56) | ||
| Study Season’s Influenza Vaccine (received) | 1038 (76) | 847 (82) | p = .07 | 55 (52–58) | p = .88 |
| Not received | 336 (24) | 259 (77) | 55 (53–56) | ||
| Interview variables, N (Col. %) | |||||
| Woman’s Age (at start of season), Years d | p = .04 | p = .04 | |||
| < 25 | 112 (8) | 93 (83) | 49 (44–54) | ||
| 25–29 | 317 (23) | 261 (82) | 55 (52–58) | ||
| 30–34 | 558 (41) | 459 (82) | 56 (54–58) | ||
| ≥ 35 | 387 (28) | 293 (76) | 54 (51–56) | ||
| Gestational Age (at start of season), Days d | p < .0005 | p < .0005 | |||
| < 137 | 339 (25) | 306 (90) | 65 (53–67) | ||
| 137–172 | 363 (26) | 283 (78) | 56 (54–59) | ||
| 173–224 | 356 (26) | 301 (85) | 53 (51–55) | ||
| ≥ 225 | 316 (23) | 216 (68) | 40 (37–43) | ||
| Race (Self-Reported) | p < .0005 | p < .0005 | |||
| White | 934 (68) | 785 (84) | 57 (56–59) | ||
| Asian | 205 (15) | 154 (75) | 52 (48–55) | ||
| Black | 64 (5) | 40 (63) | 44 (37–51) | ||
| Mixed or Other | 171 (12) | 127 (74) | 44 (40–48) | ||
| Marital Status | p = .61 | p = .003 | |||
| Married or Partnered | 1286 (94) | 1037 (81) | 55 (54–57) | ||
| Not Married and Not Partnered | 88 (6) | 69 (78) | 47 (41–52) | ||
| Education | p = .14 | p = .08 | |||
| High school or less | 119 (9) | 92 (77) | 50 (42–54) | ||
| Some college or bachelor’s degree | 744 (54) | 589 (79) | 55 (53–57) | ||
| Advanced degree | 511 (37) | 425 (83) | 55 (53–57) | ||
| Subjective social status | p = .23 | p = .77 | |||
| 1 to 3 (low) | 25 (2) | 20 (80) | 51 (41–61) | ||
| 4 to 6 (medium) | 697 (51) | 555 (80) | 55 (53–57) | ||
| 7 to 9 (high) | 632 (46) | 518 (82) | 54 (52–56) | ||
| Missing or refused | 20 (1) | 13 (65) | 57 (43–71) | ||
| Child(ren) aged < 13 years at home | p < .0005 | p = .001 | |||
| No | 644 (47) | 549 (85) | 57 (55–59) | ||
| Yes child | 730 (53) | 557 (76) | 52 (51–54) | ||
| Self-rated Health Status | p = .11 | p = .24 | |||
| Poor, fair, or good | 301 (22) | 234 (78) | 52 (49–55) | ||
| Very good | 548 (40) | 435 (79) | 55 (53–57) | ||
| Excellent | 525 (38) | 437 (83) | 55 (53–54) | ||
| Smoking | p = .34 | p = .68 | |||
| Never smoked | 1016 (74) | 824 (81) | 55 (53–56) | ||
| Previously or currently smoke | 358 (26) | 282 (79) | 54 (51–57) | ||
| Stressful events in past year (number) | p = .11 | p = .001 | |||
| 0 | 276 (20) | 231 (84) | 55 (54–58) | ||
| 1 | 349 (25) | 290 (83) | 56 (54–59) | ||
| 2 | 310 (23) | 243 (78) | 57 (55–60) | ||
| 3 or more | 439 (32) | 342 (78) | 51 (48–53) | ||
Abbreviations: CI Confidence interval, ARI Acute respiratory illness
aSince some women had delivery dates during the surveillance period, women differ in the number of eligible surveillance weeks; we report the percentage of eligible surveillance weeks when at least one surveillance report was completed
bp-value is from Chi-square test of difference between groups in percentage completing at least one surveillance
cp-value is from Student’s t-test or F-ratio comparing the mean percentage of weeks when surveillance was completed between groups
dWomen’s age and age of fetus were calculated using a common reference date, which was the start of the influenza season at each study site; gestational age is reported in quartiles