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Each row is one question a systematic review asked: who, what, compared with what, and which outcome, with the effect it found and how certain that is. Words match anywhere in the field.

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Intervention or exposure

Comparison

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Review versions

915 questions in 93 reviews · Emergency and Critical Care

current versions

No studies 141 · 15.4%Ungraded 22 · 2.4%Very low 216 · 23.6%Low 272 · 29.7%Moderate 188 · 20.5%High 76 · 8.3%

Ungraded means an effect was reported without a GRADE rating; it is not a gap. No studies means the review found nothing to answer the question. The six categories are a display order, not a score.

Question	Effect	Evidence	Status / GRADE
ChAdOx1 – AstraZeneca + University of Oxford vs placebo Confirmed symptomatic COVID‐19b Efficacy and safety of COVID‐19 vaccines (2022) · Cochrane	no estimate extracted	5 studies · 43390 participants	High
ChAdOx1 – AstraZeneca + University of Oxford vs placebo Severe or critical COVID‐19 Efficacy and safety of COVID‐19 vaccines (2022) · Cochrane	no estimate extracted	NR	No studies
ChAdOx1 – AstraZeneca + University of Oxford vs placebo All‐cause mortalityf Efficacy and safety of COVID‐19 vaccines (2022) · Cochrane	RR 0.48 [0.2, 1.14]	5 studies · 56727 participants	Low
ChAdOx1 – AstraZeneca + University of Oxford vs placebo Systemic reactogenicity eventsi Efficacy and safety of COVID‐19 vaccines (2022) · Cochrane	RR 3.93 [2.11, 7.29]	1 study · 256 participants	Moderate
BNT162b2 – Pfizer/BioNTech + Fosun Pharma vs placebo Severe or critical COVID‐19e Efficacy and safety of COVID‐19 vaccines (2022) · Cochrane	no estimate extracted	1 study · 46077 participants	High
ChAdOx1 – AstraZeneca + University of Oxford vs placebo Any adverse eventl Efficacy and safety of COVID‐19 vaccines (2022) · Cochrane	no estimate extracted	7 studies · 57580 participants	Low
ChAdOx1 – AstraZeneca + University of Oxford vs placebo Serious adverse eventso Efficacy and safety of COVID‐19 vaccines (2022) · Cochrane	RR 0.88 [0.72, 1.07]	7 studies · 58182 participants	Moderate
ChAdOx1 – AstraZeneca + University of Oxford vs placebo Local reactogenicity eventsi Efficacy and safety of COVID‐19 vaccines (2022) · Cochrane	RR 6.44 [2.98, 13.92]	1 study · 256 participants	Moderate
SII‐ChAdOx1 – Serum Institute of India/AstraZeneca + University of Oxford vs ChAdOx1 – University of Oxford Confirmed SARS‐CoV‐2 infectionÂ Efficacy and safety of COVID‐19 vaccines (2022) · Cochrane	no estimate extracted	NR	No studies
SII‐ChAdOx1 – Serum Institute of India/AstraZeneca + University of Oxford vs ChAdOx1 – University of Oxford Confirmed symptomatic COVID‐19 Efficacy and safety of COVID‐19 vaccines (2022) · Cochrane	no estimate extracted	NR	No studies
SII‐ChAdOx1 – Serum Institute of India/AstraZeneca + University of Oxford vs ChAdOx1 – University of Oxford Severe or critical COVID‐19 Efficacy and safety of COVID‐19 vaccines (2022) · Cochrane	no estimate extracted	NR	No studies
SII‐ChAdOx1 – Serum Institute of India/AstraZeneca + University of Oxford vs ChAdOx1 – University of Oxford All‐cause mortalityÂ Efficacy and safety of COVID‐19 vaccines (2022) · Cochrane	no estimate extracted	NR	No studies
SII‐ChAdOx1 – Serum Institute of India/AstraZeneca + University of Oxford vs ChAdOx1 – University of Oxford Systemic reactogenicity eventsb Efficacy and safety of COVID‐19 vaccines (2022) · Cochrane	RR 0.73 [0.54, 0.98]	1 study · 400 participants	Moderate
SII‐ChAdOx1 – Serum Institute of India/AstraZeneca + University of Oxford vs ChAdOx1 – University of Oxford Any adverse evente Efficacy and safety of COVID‐19 vaccines (2022) · Cochrane	RR 0.83 [0.52, 1.33]	1 study · 400 participants	Low
SII‐ChAdOx1 – Serum Institute of India/AstraZeneca + University of Oxford vs ChAdOx1 – University of Oxford Serious adverse eventsg Efficacy and safety of COVID‐19 vaccines (2022) · Cochrane	RR 0.5 [0.08, 2.95]	1 study · 400 participants	Low
BNT162b2 – Pfizer/BioNTech + Fosun Pharma vs placebo All‐cause mortalityg Efficacy and safety of COVID‐19 vaccines (2022) · Cochrane	RR 1.07 [0.52, 2.22]	1 study · 43847 participants	Low
SII‐ChAdOx1 – Serum Institute of India/AstraZeneca + University of Oxford vs ChAdOx1 – University of Oxford Local reactogenicity eventsb Efficacy and safety of COVID‐19 vaccines (2022) · Cochrane	RR 0.76 [0.55, 1.05]	1 study · 400 participants	Low
AD26.COV2.S – Janssen Pharmaceutical Companies vs placebo Confirmed SARS‐CoV‐2 infection Efficacy and safety of COVID‐19 vaccines (2022) · Cochrane	no estimate extracted	NR	No studies
AD26.COV2.S – Janssen Pharmaceutical Companies vs placebo Confirmed symptomatic COVID‐19b Efficacy and safety of COVID‐19 vaccines (2022) · Cochrane	no estimate extracted	1 study · 39058 participants	High
AD26.COV2.S – Janssen Pharmaceutical Companies vs placebo Severe or critical COVID‐19b Efficacy and safety of COVID‐19 vaccines (2022) · Cochrane	no estimate extracted	1 study · 39058 participants	High
AD26.COV2.S – Janssen Pharmaceutical Companies vs placebo All‐cause mortalityb Efficacy and safety of COVID‐19 vaccines (2022) · Cochrane	RR 0.25 [0.09, 0.67]	1 study · 43783 participants	High
AD26.COV2.S – Janssen Pharmaceutical Companies vs placebo Serious adverse eventsb Efficacy and safety of COVID‐19 vaccines (2022) · Cochrane	RR 0.92 [0.69, 1.22]	1 study · 43783 participants	Moderate
AD26.COV2.S – Janssen Pharmaceutical Companies vs placebo Systemic reactogenicity eventse Efficacy and safety of COVID‐19 vaccines (2022) · Cochrane	RR 1.83 [1.29, 2.6]	2 studies · 7222 participants	High
AD26.COV2.S – Janssen Pharmaceutical Companies vs placebo Any adverse eventh Efficacy and safety of COVID‐19 vaccines (2022) · Cochrane	no estimate extracted	2 studies · 7222 participants	Low
Gam‐COVID‐VAC – Sputnik V vs placebo Confirmed SARS‐CoV‐2 infection Efficacy and safety of COVID‐19 vaccines (2022) · Cochrane	no estimate extracted	NR	No studies
Gam‐COVID‐VAC – Sputnik V vs placebo Confirmed symptomatic COVID‐19b Efficacy and safety of COVID‐19 vaccines (2022) · Cochrane	no estimate extracted	1 study · 18695 participants	Moderate
BNT162b2 – Pfizer/BioNTech + Fosun Pharma vs placebo Systemic reactogenicity events Efficacy and safety of COVID‐19 vaccines (2022) · Cochrane	no estimate extracted	NR	No studies
Gam‐COVID‐VAC – Sputnik V vs placebo Severe or critical COVID‐19b Efficacy and safety of COVID‐19 vaccines (2022) · Cochrane	no estimate extracted	1 study · 19866 participants	Moderate
Gam‐COVID‐VAC – Sputnik V vs placebo All‐cause mortalityf Efficacy and safety of COVID‐19 vaccines (2022) · Cochrane	RR 0.99 [0.1, 9.54]	1 study · 21862 participants	Very low
Gam‐COVID‐VAC – Sputnik V vs placebo Systemic reactogenicity events Efficacy and safety of COVID‐19 vaccines (2022) · Cochrane	no estimate extracted	NR	No studies
Gam‐COVID‐VAC – Sputnik V vs placebo Any adverse event Efficacy and safety of COVID‐19 vaccines (2022) · Cochrane	no estimate extracted	NR	No studies
Gam‐COVID‐VAC – Sputnik V vs placebo Serious adverse eventsf Efficacy and safety of COVID‐19 vaccines (2022) · Cochrane	RR 0.65 [0.39, 1.07]	1 study · 21862 participants	Low
Gam‐COVID‐VAC – Sputnik V vs placebo Local reactogenicity events Efficacy and safety of COVID‐19 vaccines (2022) · Cochrane	no estimate extracted	NR	No studies
CoronaVac – Sinovac vs placebo Confirmed SARS‐CoV‐2 infectionÂ Efficacy and safety of COVID‐19 vaccines (2022) · Cochrane	no estimate extracted	NR	No studies
CoronaVac – Sinovac vs placebo Confirmed symptomatic COVID‐19b Efficacy and safety of COVID‐19 vaccines (2022) · Cochrane	no estimate extracted	2 studies · 19852 participants	Low
CoronaVac – Sinovac vs placebo Severe or critical COVID‐19b Efficacy and safety of COVID‐19 vaccines (2022) · Cochrane	no estimate extracted	2 studies · 19852 participants	Low
CoronaVac – Sinovac vs placebo All‐cause mortalityh Efficacy and safety of COVID‐19 vaccines (2022) · Cochrane	RR 0.5 [0.05, 5.52]	2 studies · 22610 participants	Low
BNT162b2 – Pfizer/BioNTech + Fosun Pharma vs placebo Any adverse eventi Efficacy and safety of COVID‐19 vaccines (2022) · Cochrane	no estimate extracted	3 studies · 46149 participants	Low
CoronaVac – Sinovac vs placebo Systemic reactogenicity eventsj Efficacy and safety of COVID‐19 vaccines (2022) · Cochrane	RR 1.19 [1, 1.42]	6 studies · 23966 participants	Low
CoronaVac – Sinovac vs placebo Any adverse evento Efficacy and safety of COVID‐19 vaccines (2022) · Cochrane	RR 1.09 [1.07, 1.11]	6 studies · 23367 participants	High
CoronaVac – Sinovac vs placebo Serious adverse eventsr Efficacy and safety of COVID‐19 vaccines (2022) · Cochrane	RR 0.97 [0.62, 1.51]	4 studies · 23139 participants	Low
CoronaVac – Sinovac vs placebo Local reactogenicity eventsj Efficacy and safety of COVID‐19 vaccines (2022) · Cochrane	RR 1.76 [1.69, 1.82]	6 studies · 23962 participants	High
WIBP‐CorV – Sinopharm‐Wuhan vs placebo Confirmed SARS‐CoV‐2 infectionb Efficacy and safety of COVID‐19 vaccines (2022) · Cochrane	no estimate extracted	1 study · 25449 participants	High
WIBP‐CorV – Sinopharm‐Wuhan vs placebo Confirmed symptomatic COVID‐19b Efficacy and safety of COVID‐19 vaccines (2022) · Cochrane	no estimate extracted	1 study · 25480 participants	High
WIBP‐CorV – Sinopharm‐Wuhan vs placebo Severe or critical COVID‐19 Efficacy and safety of COVID‐19 vaccines (2022) · Cochrane	no estimate extracted	NR	No studies
WIBP‐CorV – Sinopharm‐Wuhan vs placebo All‐cause mortalityÂ Efficacy and safety of COVID‐19 vaccines (2022) · Cochrane	no estimate extracted	NR	No studies
WIBP‐CorV – Sinopharm‐Wuhan vs placebo Systemic reactogenicity eventse Efficacy and safety of COVID‐19 vaccines (2022) · Cochrane	RR 0.99 [0.95, 1.03]	2 studies · 27029 participants	High
WIBP‐CorV – Sinopharm‐Wuhan vs placebo Any adverse eventh Efficacy and safety of COVID‐19 vaccines (2022) · Cochrane	RR 0.96 [0.93, 0.98]	2 studies · 27029 participants	High
BNT162b2 – Pfizer/BioNTech + Fosun Pharma vs placebo Serious adverse eventsi Efficacy and safety of COVID‐19 vaccines (2022) · Cochrane	RR 1.3 [0.55, 3.07]	2 studies · 46107 participants	Low
WIBP‐CorV – Sinopharm‐Wuhan vs placebo Serious adverse eventsi Efficacy and safety of COVID‐19 vaccines (2022) · Cochrane	RR 0.83 [0.6, 1.15]	2 studies · 27029 participants	Low