To understand how effective a vaccine is, it is essential not to compare it with others but to know what a vaccine is supposed to do in the first place. Here’s why it may not be the right way to determine which vaccine is more effective against Covid-19… (Image: News18 Creative)

These numbers are arguably not even the most important factors to determine how effective vaccines are. (Image: News18 Creative)

Vaccine efficacy rate is calculated in large clinical trials with a sample size of tens of thousands of people. Participants are broken into two groups. They are then monitored over several months to see how many got COVID-19 from each group. (Image: News18 Creative)

Let’s take a look at the Pfizer vaccine case study. Here’s to understand how the infected people falling in ach group (vaccinated or placebo) determines a vaccine’s efficacy. (Image: News18 Creative)

Real Pfizer vaccine efficacy is 95 percent which means significant percentage reduction of disease in the vaccinated group. (Image: News18 Creative)

Here are some other factors determining how effective a vaccine truly is. (Image: News18 Creative)

For head-to-head comparison of vaccines, the trials need to have the same inclusion criteria in the same parts of the world at the same time. (Image: News18 Creative)

According to the experts, the goal of COVID-19 vaccines is not to eliminate the virus, but to remove its ability to cause serious hospitalization and death. (Image: News18 Creative)

COVID-19 | A look at why not to compare vaccine efficacy to know its effectiveness

Should we compare effectiveness of vaccines on the basis of their efficacy rates? Here’s why it may not be the right way to determine which vaccine is more effective against Covid-19…