Skip to main content
. 2018 Feb 1;2018(2):CD004876. doi: 10.1002/14651858.CD004876.pub4

Comparison 8. Influenza vaccines versus no vaccination: cohort studies in community‐dwellers.

Outcome or subgroup title No. of studies No. of participants Statistical method Effect size
8.1 Influenza 2 18249 Risk Ratio (M‐H, Random, 95% CI) 0.19 [0.02, 2.01]
8.1.1 Epidemic year ‐ vaccine matching 1 427 Risk Ratio (M‐H, Random, 95% CI) 0.05 [0.01, 0.37]
8.1.2 Epidemic year ‐ vaccine matching absent or unknown 0 0 Risk Ratio (M‐H, Random, 95% CI) Not estimable
8.1.3 Non‐epidemic year ‐ vaccine matching 1 17822 Risk Ratio (M‐H, Random, 95% CI) 0.50 [0.27, 0.91]
8.1.4 Non‐epidemic year ‐ vaccine matching absent or unknown 0 0 Risk Ratio (M‐H, Random, 95% CI) Not estimable
8.2 Influenza‐like illness 4 9613 Risk Ratio (M‐H, Random, 95% CI) 0.75 [0.42, 1.33]
8.2.1 Epidemic year ‐ vaccine matching 0 0 Risk Ratio (M‐H, Random, 95% CI) Not estimable
8.2.2 Epidemic year ‐ vaccine matching absent or unknown 0 0 Risk Ratio (M‐H, Random, 95% CI) Not estimable
8.2.3 Non‐epidemic year ‐ vaccine matching 2 4636 Risk Ratio (M‐H, Random, 95% CI) 1.08 [0.58, 2.03]
8.2.4 Non‐epidemic year ‐ vaccine matching absent or unknown 1 268 Risk Ratio (M‐H, Random, 95% CI) 0.85 [0.16, 4.55]
8.2.5 Epidemic year ‐ vaccine not matching 1 4709 Risk Ratio (M‐H, Random, 95% CI) 0.44 [0.24, 0.81]
8.3 Pneumonia 2 18090 Risk Ratio (M‐H, Random, 95% CI) 0.88 [0.64, 1.20]
8.3.1 Epidemic year ‐ vaccine matching 0 0 Risk Ratio (M‐H, Random, 95% CI) Not estimable
8.3.2 Epidemic year ‐ vaccine matching absent or unknown 0 0 Risk Ratio (M‐H, Random, 95% CI) Not estimable
8.3.3 Non‐epidemic year ‐ vaccine matching 1 17822 Risk Ratio (M‐H, Random, 95% CI) 0.87 [0.63, 1.19]
8.3.4 Non‐epidemic year ‐ vaccine matching absent or unknown 1 268 Risk Ratio (M‐H, Random, 95% CI) 3.00 [0.16, 57.42]
8.4 Hospitalisation for flu or pneumonia 9 784643 Risk Ratio (M‐H, Random, 95% CI) 0.73 [0.62, 0.85]
8.4.1 Epidemic year ‐ vaccine matching 6 727776 Risk Ratio (M‐H, Random, 95% CI) 0.74 [0.62, 0.88]
8.4.2 Epidemic year ‐ vaccine matching absent or unknown 0 0 Risk Ratio (M‐H, Random, 95% CI) Not estimable
8.4.3 Non‐epidemic year ‐ vaccine matching 1 25532 Risk Ratio (M‐H, Random, 95% CI) 0.55 [0.37, 0.83]
8.4.4 Non‐epidemic year ‐ vaccine matching absent or unknown 1 26626 Risk Ratio (M‐H, Random, 95% CI) 0.73 [0.54, 0.99]
8.4.5 Epidemic year ‐ vaccine not matching 1 4709 Risk Ratio (M‐H, Random, 95% CI) 0.89 [0.33, 2.40]
8.5 Hospitalisation for any respiratory disease 5 567299 Risk Ratio (M‐H, Random, 95% CI) 0.88 [0.54, 1.43]
8.5.1 Epidemic year ‐ vaccine matching 3 515141 Risk Ratio (M‐H, Random, 95% CI) 0.78 [0.37, 1.64]
8.5.2 Epidemic year ‐ vaccine matching absent or unknown 0 0 Risk Ratio (M‐H, Random, 95% CI) Not estimable
8.5.3 Non‐epidemic year ‐ vaccine matching 1 25532 Risk Ratio (M‐H, Random, 95% CI) 0.94 [0.79, 1.12]
8.5.4 Non‐epidemic year ‐ vaccine matching absent or unknown 1 26626 Risk Ratio (M‐H, Random, 95% CI) 1.16 [1.01, 1.34]
8.6 Deaths from flu or pneumonia 1 163391 Risk Ratio (M‐H, Random, 95% CI) 0.87 [0.70, 1.09]
8.6.1 Epidemic year ‐ vaccine matching 1 163391 Risk Ratio (M‐H, Random, 95% CI) 0.87 [0.70, 1.09]
8.6.2 Epidemic year ‐ vaccine matching absent or unknown 0 0 Risk Ratio (M‐H, Random, 95% CI) Not estimable
8.6.3 Non‐epidemic year ‐ vaccine matching 0 0 Risk Ratio (M‐H, Random, 95% CI) Not estimable
8.6.4 Non‐epidemic year ‐ vaccine matching absent or unknown 0 0 Risk Ratio (M‐H, Random, 95% CI) Not estimable
8.7 Deaths from respiratory disease 1 426668 Risk Ratio (M‐H, Random, 95% CI) 1.32 [1.25, 1.39]
8.7.1 Epidemic year ‐ vaccine matching 1 426668 Risk Ratio (M‐H, Random, 95% CI) 1.32 [1.25, 1.39]
8.8 All deaths 8 409468 Risk Ratio (M‐H, Random, 95% CI) 0.61 [0.47, 0.80]
8.8.1 Epidemic year ‐ vaccine matching 4 300332 Risk Ratio (M‐H, Random, 95% CI) 0.59 [0.50, 0.70]
8.8.2 Epidemic year ‐ vaccine matching absent or unknown 0 0 Risk Ratio (M‐H, Random, 95% CI) Not estimable
8.8.3 Non‐epidemic year ‐ vaccine matching 3 104427 Risk Ratio (M‐H, Random, 95% CI) 0.65 [0.30, 1.39]
8.8.4 Non‐epidemic year ‐ vaccine matching absent or unknown 0 0 Risk Ratio (M‐H, Random, 95% CI) Not estimable
8.8.5 Epidemic year ‐ vaccine not matching 1 4709 Risk Ratio (M‐H, Random, 95% CI) 3.89 [0.90, 16.89]
8.9 Hospitalisation for heart disease 6 433934 Risk Ratio (M‐H, Random, 95% CI) 0.87 [0.67, 1.12]
8.9.1 Epidemic year ‐ vaccine matching 4 381776 Risk Ratio (M‐H, Random, 95% CI) 0.74 [0.56, 0.97]
8.9.2 Epidemic year ‐ vaccine matching absent or unknown 0 0 Risk Ratio (M‐H, Random, 95% CI) Not estimable
8.9.3 Non‐epidemic year ‐ vaccine matching 1 25532 Risk Ratio (M‐H, Random, 95% CI) 1.06 [0.81, 1.38]
8.9.4 Non‐epidemic year ‐ vaccine matching absent or unknown 1 26626 Risk Ratio (M‐H, Random, 95% CI) 1.59 [1.07, 2.36]
8.10 Combined outcome: all deaths or severe respiratory illness 3 290819 Risk Ratio (M‐H, Random, 95% CI) 0.71 [0.58, 0.85]
8.10.1 Epidemic year ‐ vaccine matching 2 132365 Risk Ratio (M‐H, Random, 95% CI) 0.80 [0.42, 1.55]
8.10.2 Epidemic year ‐ vaccine matching absent or unknown 1 158454 Risk Ratio (M‐H, Random, 95% CI) 0.74 [0.69, 0.80]