Experimental and Observational | Categories by vaccine or variant | No. Studies (Sample Size) | Pooled Risk Ratio | Between studies, heterogeneity assessment (%) | |
---|---|---|---|---|---|
\({\text{I}}^{2}\) | P | ||||
Total: Experimental | - | 9 (71,487) | 0.50 (0.35, 0.71) | 79.68% | 0.001 |
Total: Observational | - | 17 (353,425) | 0.28 (0.18, 0.45) | 99.29% | 0.001 |
Experimental by Vaccine | Astra | 9 (142,974) | 0.50 (0.35, 0.71) | 79.68% | 0.001 |
Observational by Vaccine | Baharat | 1 (2136) | 0.82 (0.75, 0.89) | - | - |
Janssen | 1 (3689) | 0.53 (0.41, 0.69) | - | - | |
Moderna | 2 (79,235) | 0.19 (0.17, 0.22) | - | - | |
Astra | 4 (72,382) | 0.18 (0.04, 0.84) | 44.19% | 0.074 | |
Pfizer | 8 (195,706) | 0.28 (0.18, 0.44) | 77.02% | 0.058 | |
SARS COV-2 vaccine | 1 (277) | 1.01 (0.64, 1.60) | - | - | |
Experimental by Variant | Alpha | 1 (17,662) | 0.44 (0.36, 0.53) | - | - |
Beta | 1 (1467) | 0.79 (0.43, 1.44) | - | - | |
Gamma | 2 (18,866) | 0.31 (0.18, 0.54) | - | - | |
Other | 2 (18,866) | 0.31 (0.22, 0.45) | - | - | |
Un determined | 1 (9433) | 0.45 (0.27, 0.74) | - | - | |
Non-Beta | 1 (1467) | 0.79 (0.43, 1.44) | - | - | |
Observational by Variant | Alpha | 3 (259,812) | 0.20 (0.17, 0.23) | 76.62% | 0.003 |
Delta | 5 (8747) | 0.52 (0.27, 1.01) | 63.89% | 0.049 | |
Gamma | 1 (61,360) | 0.02 (0.02, 0.02) | - | - | |
NR | 2 (9862) | 0.31 (0.18, 0.54) | - | - |