Business
Behind the numbers: what does it mean if a Covid vaccine has ‘90% efficacy’? – The Guardian
Confusion surrounds the vaccines’ effectiveness. The leading Cambridge professor clarifies the data behind the trials

Imagine 100 people are ill with Covid-19. 90% efficacy means if only theyd had the vaccine, on average only 10 would have got ill. Vaccine efficacy is the relative reduction in the risk: whatever your risk was before, it is reduced by 90% if you get vaccinated. There is a lot of confusion about this number: it does not mean there is a 10% chance of getting Covid-19 if vaccinated that chance will be massively lower than 10%.
Researchers estimate efficacy by comparing numbers of new cases in vaccinated…
-
General19 hours ago
German backpacker Carolina Wilga found alive in WA’s outback
-
Noosa News21 hours ago
Australian NFL player Laki Tasi comes home to convince kids to switch codes
-
Business21 hours ago
How $1,000 a month in this ASX ETF could turn into $500,000
-
Business22 hours ago
Here’s my big problem with the ASX’s Vanguard International Shares ETF (VGS)