Table 2.
Demographic Characteristics and Comorbid Medical Disorders for the Trivalent Influenza Vaccine Vaccination and Non-Vaccination Groups Before Propensity Score Matching
| 2007 | 2008 | ||||||
|---|---|---|---|---|---|---|---|
| Vaccinated (36,433) | Non-Vaccinated (57,112) | p-value | Vaccinated (40,702) | Non-Vaccinated (59,820) | p-value | ||
| Gender | Male | 50.8% | 49.6% | 0.0003 | 50.4% | 49.6% | 0.012 |
| Female | 49.2% | 50.4% | 49.6% | 50.4% | |||
| Age (years) | 65–74 | 45.8% | 42.2% | <0.001 | 43.9% | 41.6% | <0.001 |
| 75–84 | 45.7% | 42.2% | 47.0% | 40.5% | |||
| >85 | 8.5% | 15.6% | 9.2% | 17.9% | |||
| Geographic region | North | 35.9% | 45.4% | <0.001 | 37.1% | 44.7% | <0.001 |
| Central | 29.2% | 23.0% | 28.7% | 23.1% | |||
| South | 30.5% | 27.3% | 29.9% | 27.7% | |||
| East | 4.4% | 4.4% | 4.3% | 4.5% | |||
| Urbanization level | 1 (Most urbanized) | 19.2% | 26.6% | <0.001 | 20.2% | 26.4% | <0.001 |
| 2 | 23.1% | 25.5% | 23.5% | 25.5% | |||
| 3 | 16.2% | 16.7% | 16.4% | 16.6% | |||
| 4 | 21.7% | 17.6% | 21.3% | 17.7% | |||
| 5 | 5.0% | 3.3% | 4.7% | 3.4% | |||
| 6 | 14.7% | 10.3% | 14.0% | 10.5% | |||
| Socioeconomic status | Low | 30.7% | 38.6% | <0.001 | 31.2% | 38.2% | <0.001 |
| Moderate | 19.5% | 20.5% | 18.5% | 19.8% | |||
| High | 49.8% | 40.9% | 50.3% | 42.0% | |||
| Number of comorbidities | 0 | 17.3% | 24.5% | <0.001 | 17.2% | 24.6% | <0.001 |
| 1–3 | 69.4% | 63.8% | 70.2% | 64.0% | |||
| >3 | 13.4% | 11.6% | 12.6% | 11.3% | |||
| URI OPD in prior year | 1.6 | 1.1 | <0.001 | 1.5 | 0.9 | <0.001 | |
| Number of outpatient visits | 29.1 | 18 | <0.001 | 28.8 | 16.6 | <0.001 | |
| Catastrophic illness | Yes | 12.4% | 19.4% | <0.001 | 12.4% | 21.4% | <0.001 |
| No | 87.6% | 80.6% | 87.6% | 78.7% | |||
| Recent intestinal disorder | Yes | 14.2% | 9.0% | <0.001 | 12.7% | 7.5% | <0.001 |
| No | 85.8% | 91.1% | 87.3% | 92.5% | |||
Abbreviation: URI OPD, outpatient department visit for upper respiratory infection.