Question

COVID-19 vaccine was tested in a randomised controlled trial in which 400,000 adults selected from the population were divided into two similar groups. Adults in one group were given the vaccine while those in the other group were given a placebo. At a later date the number of adults contracting COVID-19 in each group were determined. In the vaccine group, there were 56 cases of COVID-19 out of 200,000 adults while in the placebo group, there were 142 cases of COVID-19 of the 200,000 adults. a) Draw a 2 by 2 table [2 marks] b) Carry out a significance test to compare the incidence of COVID-19 in the two groups [7 marks] c) Write a brief report on your conclusion about the effectiveness of the COVID-19 vaccine. [2

Answer 1