Table 3.
Univariate logistic regression models of potential variables associated with influenza vaccination (n = 816).
| Correlates associated with influenza vaccination | Vaccinated (n = 509) | Non-vaccinated (n = 307) | Odds ratio (OR) (95%CI) | p-Value |
|---|---|---|---|---|
| % (n) | % (n) | |||
| Demographic characteristics | ||||
| Gender: female (vs. male) | 82.3 (419) | 78.8 (242) | 1.250 (0.876–1.785) | 0.219 |
| Age: <85 (vs. ≥85) | 88.8 (452) | 83.7 (257) | 1.543 (1.024–2.323) | 0.038* |
| Living condition: living with family members (vs. living alone) | 68.2 (347) | 73.9 (227) | 1.325 (0.966–1.816) | 0.081 |
| Education: primary to tertiary (vs. no education) | 51.9 (264) | 57.3 (176) | 1.247 (0.937–1.658) | 0.130 |
| Objective assessments | ||||
| The Chinese version of Mini-Mental State Examination (CMMSE) | ||||
| 19–24 (vs. ≤18) | 32.4 (165) | 26.1 (80) | 2.108 (1.410–3.154) | <0.001** |
| 25–30 (vs. ≤18) | 56.4 (287) | 52.1(160) | 2.424 (1.557–3.774) | <0.001** |
| The Chinese version of Modified Barthel Index (CMBI) | ||||
| 61–80 (vs. ≤60) | 3.3 (17) | 9.1 (28) | 1.214 (0.384–3.836) | 0.741 |
| 81–100(vs. ≤60) | 95.5 (486) | 87.0 (267) | 3.640 (1.351–9.808) | 0.011* |
| Self perceived health status | ||||
| Good (vs. very good) | 26.5 (135) | 30.6 (94) | 1.632 (1.007–2.646) | 0.047* |
| Fair to poor (vs. very good) | 64.8 (330) | 53.1 (163) | 2.300 (1.472–3.595) | <0.001** |
| Chronic illness | ||||
| Number of chronic illnesses | ||||
| Three or above (vs. <3) | 17.7 (90) | 11.4 (35) | 0.599 (0.394–0.911) | 0.017* |
| Types of chronic illness | ||||
| Diabetes mellitus (yes vs. no) | 18.3 (93) | 16.6 (51) | 1.122 (0.771–1.633) | 0.547 |
| Hypertension (yes vs. no) | 45.4 (231) | 35.8 (110) | 1.488 (1.112–1.991) | 0.008** |
| Asthma/chronic obstructive airway disease (COAD) (yes vs. no) | 9.0 (46) | 2.9 (9) | 3.289 (1.587–6.818) | 0.001** |
| Heart disease (yes vs. no) | 12.8 (65) | 10.1 (31) | 1.303 (0.828–2.051) | 0.251 |
| Immuno-compromised disease condition (yes vs. no) | 0.2 (1) | 0.3 (1) | 0.602 (0.038–9.665) | 0.720 |
| Medication allergy (yes vs. no) | 2.9 (15) | 5.5 (17) | 0.518 (0.255–1.053) | 0.065 |
| Dementia (yes vs. no) | 0.4 (2) | 0.3 (1) | 1.207(0.109–13.366) | 0.878 |
| Depression (yes vs. no) | 2.2 (11) | 2.6 (8) | 0.826 (0.328–2.076) | 0.683 |
| Others (yes vs. no) | 44.8 (228) | 37.1 (114) | 1.374 (1.028–1.836) | 0.032* |
| Hospitalization in past 12 months | ||||
| Hospital out-patient in past 12 months (vs. no out-patient follow up in past 12 months) | 75.2 (383) | 61.9 (190) | 1.872 (1.378–2.541) | <0.001** |
| Hospital in-patient in past 12 months (vs. non-hospital in-patient in past 12 months) | 23.4 (119) | 26.4 (81) | 0.851 (0.614–1.180) | 0.334 |
| Advisor of influenza vaccination | ||||
| Nursing staff of elderly center (vs. no nursing staff of elderly centers’ advice) | 81.5 (415) | 33.9 (104) | 8.493 (6.136–11.757) | <0.001** |
| Medical staff of elderly centers (vs. no medical staff's advice) | 33.0 (168) | 10.1 (31) | 4.385 (2.897–6.638) | <0.001** |
| Family members or friends (vs. no family members or friends’ advice) | 24.0 (122) | 7.2 (22) | 4.083 (2.529–6.591) | <0.001** |
| Others (vs. no others’ advice) | 9.6 (49) | 2.3 (7) | 4.559 (2.039–10.195) | <0.001** |
| Perception of influenza illness, vaccine efficacy and safety | ||||
| Know the symptom of influenza (yes vs. no) | 73.1 (372) | 61.2 (188) | 1.719 (1.271–2.324) | <0.001** |
| High chance to get influenza (yes vs. no) | 34.0 (173) | 22.8 (70) | 1.743 (1.261–2.409) | 0.001** |
| Vaccination useful (yes vs. no) | 92.3 (470) | 83.1 (255) | 2.457 (1.579–3.824) | <0.001** |
| “It is safe to receive vaccination” (yes vs. no) | 98.8 (503) | 94.8 (291) | 4.604 (1.782–11.894) | 0.002** |
| Agree recommendation that elderly over 64 should be vaccinated (yes vs. no) | 96.5 (491) | 87.9 (270) | 3.737 (2.087–6.692) | <0.001** |
| Agree free vaccination policy/recommendation for elderly | ||||
| (a) Under comprehensive social security assistance (CSSA) scheme (yes vs. no) | 95.7 (487) | 88.9 (273) | 2.757 (1.580–4.809) | <0.001** |
| (b) Living in old age home (OAH) (yes vs. no) | 95.9 (488) | 88.3 (271) | 3.087 (1.766–5.395) | <0.001** |
| (c) With chronic illness/pulmonary disease (yes vs. no) | 97.1 (494) | 88.9 (273) | 4.100 (2.194–7.661) | <0.001** |
| Consider vaccination if all >64 years old elderly eligible to receive free vaccination (yes vs. no) | 96.5 (491) | 63.5 (193) | 15.656 (9.266–26.454) | <0.001** |
| Consider vaccination in the subsequent years (yes vs. no) | 90.4 (460) | 33.2 (102) | 18.865 (12.923–27.541) | <0.001** |
| Reasons to be considered before vaccination | ||||
| (a) Is it free? (yes vs. no) | 36.3 (185) | 42.3 (130) | 0.777 (0.582–1.039) | 0.088 |
| (b) Is it safe? (yes vs. no) | 73.9 (376) | 54.7 (168) | 2.339 (1.734–3.155) | <0.001** |
| (c) Is it effective? (yes vs. no) | 58.4 (297) | 44.6 (137) | 1.738 (1.306–2.314) | <0.001** |
| (d) Others (e.g. distance, time or no specific reason)? (yes vs. no) | 11.2 (57) | 30.0 (92) | 0.295 (0.204–0.426) | <0.001** |
| After SARS and Avian influenza | ||||
| “There is a need on influenza vaccination after Severe Acute Respiratory Syndrome (SARS) and Avian influenza” (yes vs. no) | 91.9 (468) | 63.8 (196) | 6.464 (4.354–9.597) | <0.001** |
| “Influenza vaccination effectively reduce the chance to get SARS and Avian influenza” (yes vs. no) | 92.9 (473) | 69.4 (213) | 5.798 (3.822–8.797) | <0.001** |
*
p ≤ 0.05.
**
p ≤ 0.01.