How to test if a vaccine has been effective?
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Vaccine effectiveness can be assessed through various methods. One approach is to conduct randomized controlled trials (RCTs) . RCTs involve comparing the outcomes of individuals who receive the vaccine with those who do not, allowing for a direct measurement of the vaccine's efficacy. Another method is the use of observational designs, such as cohort and case-control studies, which are useful when evaluating vaccines with large effectiveness . Additionally, regression discontinuity design (RDD) using observational data can be employed to estimate vaccine effects when eligibility for the intervention is based on a defined cutoff, such as age . This approach provides a higher level of causal inference evidence and more realistic results. Furthermore, assessing vaccine effectiveness may involve analyzing immune responses post-vaccination and considering the type of infecting agent, which can be done through correlate of protection (CoP) and sieve analyses . These methods allow for a comprehensive evaluation of the vaccine's effect in preventing disease and reducing its severity.
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1 Citations | The paper proposes a unified framework for evaluating vaccine efficacy by assessing the correlate of protection (CoP) and sieve effects. It outlines hypothesis testing procedures and suggests using flexible parametric models to estimate the effects. However, it does not explicitly mention how to test if a vaccine has been effective. |
10 Feb 2022 | The paper discusses using a regression discontinuity design (RDD) to evaluate the real-world effectiveness of a vaccine. RDD is a method to quantify the effect of an intervention, such as a vaccine, when eligibility is based on a defined cutoff, such as age. This approach provides a higher level of causal inference evidence and more realistic results compared to randomized controlled trials. |
5 Citations | The paper proposes two adaptive tests to assess vaccine effectiveness: the weighted two-part test and the randomized test. These tests consider both disease incidence and disease severity as outcomes to evaluate the vaccine effect. |
5 Citations | The paper does not provide a direct answer to the query. The paper discusses proxies for assessing the vaccine effect on transmission at a point in time, but it does not provide specific guidelines on how to test if a vaccine has been effective. |
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