COVID-19 vaccine effectiveness

If you want to see all comparisons, please click here

SARS-CoV-2 strain HBO2 vs Placebo

You will find below the forest plots for this comparison with the general characteristics and risk of bias assessment for all RCTs identified.
Of note all trials may not be included in the synthesis.

Forest plots

Evidence profile

Summary of findings

Trial Type Comparisons Design Participants Sample size Overall risk
of bias
Highest assessment
Full description
Intervention 1 Intervention 2
NCT04510207, ChiCTR2000034780
Sinopharm - China National Biotec Group Company Limited
Al Kaabi N, JAMA, 2021

Full text
Inactivated virus




Phase 3
Healthy adults free of known COVID-19 or HIV infection at 3 centres in United Arab Emirates and Bahrain N=40411
Some concerns

Full description

For risk of bias assessment, we are considering the “effect of assignment to intervention” which might not be the analysis planned and reported by investigators. Consequently, when investigators planned to assess and report the “per-protocol” effect, the risk of bias for domain 2 may be evaluated as “some concerns”. We will contact investigators to obtain the results of the intent-to-treat analysis.