## 1. Introduction

“There may be much more complexity to the ‘95% effective’ announcement than meets the eye—or perhaps not. Only full transparency and rigorous scrutiny of the data will allow for informed decision making. The data must be made public.”

“Provide absolute risks, not just relative risks. Patients are unduly influenced when risk information is presented using a relative risk approach; this can result in suboptimal decisions. Thus, an absolute risk format should be used.”

## 2. Critical Appraisal of Vaccine Efficacy

## 3. 2 × 2 Contingency Tables and Epidemiologic Equations

## 4. Discussion

“…critical appraisal knowledge and skills are limited among physicians,” and “use of relative effect measures was associated with greater perceptions of medication effectiveness and intent to prescribe, compared with the use of absolute effect measures.”[29]

## 5. Conclusions

## Funding

## Institutional Review Board Statement

## Informed Consent Statement

## Data Availability Statement

## Acknowledgments

## Conflicts of Interest

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Infection | No Infection | ||
---|---|---|---|

Vaccine | a | b | a + b |

Placebo | c | d | c + d |

**Table 2.**2 × 2 contingency table for SARS-CoV-2 infection in Pfzier/BioNTech vaccine clinical trial.

Infection | No Infection | ||
---|---|---|---|

BNT162b2 | 8 | 21,712 | 21,720 |

Placebo | 162 | 21,564 | 21,726 |

Infection | No Infection | ||
---|---|---|---|

mRNA-1273 | 11 | 15,199 | 15,210 |

Placebo | 185 | 15,025 | 15,210 |

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