TABLE 2—
Factors Associated With Influenza Vaccination Uptake: Singapore, November 2017–July 2018
| Variable | Vaccinated (n = 473), No. (%) | Not Vaccinated (n = 8364), No. (%) | AOR (95% CI) |
| Clinic undergoing intervention period (vs control period) | 259 (54.8) | 4119 (49.2) | 1.43 (0.99, 2.07) |
| Study phase Nov–Feb (vs Apr–Jul) | 272 (57.5) | 4272 (51.1) | 1.27 (0.86, 1.87) |
| Age group, y | |||
| 65–69 | 211 (44.6) | 3386 (40.5) | 1 (Ref) |
| 70–74 | 128 (27.1) | 2283 (27.3) | 0.98 (0.77, 1.23) |
| 75–79 | 70 (14.8) | 1324 (15.8) | 0.99 (0.74, 1.32) |
| 80–84 | 44 (9.3) | 743 (8.9) | 1.00 (0.70, 1.42) |
| ≥ 85 | 20 (4.2) | 628 (7.5) | 0.58 (0.35, 0.94) |
| Male gender | 221 (46.7) | 3767 (45.0) | 1.08 (0.89, 1.31) |
| Ethnic group | |||
| Chinese | 413 (87.3) | 6670 (79.7) | 1 (Ref) |
| Malay | 20 (4.2) | 624 (7.5) | 0.63 (0.39, 1.00) |
| Indian | 13 (2.8) | 341 (4.1) | 0.70 (0.39, 1.25) |
| Others | 9 (1.9) | 217 (2.6) | 0.67 (0.33, 1.33) |
| Not stated | 18 (3.8) | 512 (6.1) | 0.85 (0.51, 1.41) |
| Rental or smaller housing flats | 19 (4.0) | 510 (6.1) | 0.63 (0.39, 1.03) |
| On follow-up for diabetes, hypertension, or hyperlipidemia | 170 (35.9) | 1868 (22.3) | 1.61 (1.29, 2.00) |
| On follow-up for COPD or asthma | 8 (1.7) | 83 (1.0) | 1.27 (0.60, 2.72) |
| No. of elderly patients (≥ 65 y) seen by clinic over 4 mo | |||
| 0–100 (5 clinics) | 18 (3.8) | 573 (6.9) | 0.28 (0.09, 0.88) |
| 101–200 (8 clinics) | 93 (19.7) | 2344 (28.0) | 0.39 (0.16, 0.94) |
| 201–300 (5 clinics) | 224 (47.4) | 2135 (25.5) | 1 (Ref) |
| > 300 (4 clinics) | 138 (29.2) | 3312 (39.6) | 0.41 (0.16, 1.10) |
Note. AOR = adjusted odds ratio; CI = confidence interval; COPD = chronic obstructive pulmonary disease. Multilevel logistic regression model with fixed intervention effect, fixed period effect, random cluster effect (by clinic), and random cluster-by-period effect.