Table 3.
Crudea and adjustedb ORs for visiting a health service, by severity indicator
| Severity Indicator | Crude ORs (95% CI)a | Fully-adjusted ORs (95% CI) | Likelihood Ratio Test P-value for fully-adjusted model |
|---|---|---|---|
| Symptoms | |||
| ARI | 1 | 1 | <0.0001 |
| ILI-No Fever | 2.72 (2.12–3.48) | 1.58 (1.11–2.25) | |
| ILI-Fever | 6.34 (4.82–8.35) | 2.52 (1.67–3.80) | |
| ILI-Fever, with phlegm | 17.82 (12.95–24.51) | 5.99 (3.75–9.56) | |
| Duration (days) | |||
| 0–3 | 1 | 1 | <0.0001 |
| 4–7 | 2.35 (1.92–2.86) | 2.18 (1.63–2.91) | |
| 8–14 | 3.59 (2.82–4.56) | 4.03 (2.81–5.79) | |
| ≥ 15 | 6.99 (5.22–9.36) | 4.62 (3.03–7.03) | |
| Health-score decrease (%) | |||
| 0–10 | 1 | 1 | <0.0001 |
| 10.1–20 | 1.46 (1.00–2.11) | 1.56 (1.00–2.43) | |
| 20.1–30 | 2.58 (1.76–3.79) | 2.49 (1.56–3.97) | |
| 30.1–50 | 5.32 (3.70–7.65) | 3.73 (2.39–5.81) | |
| ≥ 50.1 | 14.38 (9.45–21.88) | 5.54 (3.41–8.99) | |
aThe crude ORs include all four years of data. Due to the inclusion of health-score, for which data was not collected in the 2011–12 season, the fully-adjusted model excludes 2011–12. Crude analyses excluding 2011–12 showed similar results to the crude analyses presented here (Additional file 6: Table S3). bAdjusted for all other severity indicators and confounders