COVID-19 Vaccines — Study Scorecard

Pfizer-BioNTech BNT162b2 Phase 3

Polack et al., NEJM 2020

7/9

Sample size N = 43,548

Follow-up 2 months (median)

Reported efficacy 95% against symptomatic COVID-19

Funding BioNTech / Pfizer (manufacturer)

7/9 criteria met (78%)

Criterion	Met
Control Group	✅
Randomized	✅
Double-Blind	✅
Placebo-Controlled	✅
Large Sample (1,000+)	✅
Long Follow-up (1yr+)	❌
Independent Funding	❌
Peer-Reviewed	✅
Results Reproduced	✅

Moderna mRNA-1273 Phase 3

Baden et al., NEJM 2021

7/9

Sample size N = 30,420

Follow-up 2 months (median)

Reported efficacy 94.1% against symptomatic COVID-19

Funding NIAID (federal) + Moderna

7/9 criteria met (78%)

Criterion	Met
Control Group	✅
Randomized	✅
Double-Blind	✅
Placebo-Controlled	✅
Large Sample (1,000+)	✅
Long Follow-up (1yr+)	❌
Independent Funding	❌
Peer-Reviewed	✅
Results Reproduced	✅

Johnson & Johnson Ad26.COV2.S Phase 3

Sadoff et al., NEJM 2021

7/9

Sample size N = 43,783

Follow-up 1 month

Reported efficacy 66.9% against moderate-to-severe COVID-19 (at 28 days)

Funding Janssen / J&J (manufacturer)

7/9 criteria met (78%)

Criterion	Met
Control Group	✅
Randomized	✅
Double-Blind	✅
Placebo-Controlled	✅
Large Sample (1,000+)	✅
Long Follow-up (1yr+)	❌
Independent Funding	❌
Peer-Reviewed	✅
Results Reproduced	✅

Oxford-AstraZeneca ChAdOx1 Phase 2/3

Voysey et al., Lancet 2021

5/9

Sample size N = 11,636

Follow-up 3 months

Reported efficacy 70.4% (pooled across dose regimens)

Funding UK Vaccine Taskforce / University of Oxford

5/9 criteria met (56%)

Criterion	Met
Control Group	✅
Randomized	✅
Double-Blind	❌
Placebo-Controlled	❌
Large Sample (1,000+)	✅
Long Follow-up (1yr+)	❌
Independent Funding	✅
Peer-Reviewed	✅
Results Reproduced	❌

Active vaccine control (meningococcal) used instead of saline placebo.

Side-by-Side Comparison

Criterion	Pfizer-BioNTech BNT162b2 Phase 3	Moderna mRNA-1273 Phase 3	Johnson & Johnson Ad26.COV2.S Phase 3	Oxford-AstraZeneca ChAdOx1 Phase 2/3
Control Group	✅	✅	✅	✅
Randomized	✅	✅	✅	✅
Double-Blind	✅	✅	✅	❌
Placebo-Controlled	✅	✅	✅	❌
Large Sample (1,000+)	✅	✅	✅	✅
Long Follow-up (1yr+)	❌	❌	❌	❌
Independent Funding	❌	❌	❌	✅
Peer-Reviewed	✅	✅	✅	✅
Results Reproduced	✅	✅	✅	❌
Total score	7/9	7/9	7/9	5/9

Methodology note: A lower score does not mean a vaccine is unsafe or ineffective. It means the published evidence has methodological gaps — shorter follow-up, manufacturer funding, or non-standard controls. We evaluate methodology only. Consult your healthcare provider about vaccination decisions.

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