Jab fears explained: a base rate fallacy
Why increasing numbers of Covid infections among the vaccinated can be explained by a statistical phenomenon.
As some countries rapidly roll out vaccination programmes, there have been concerns that increases in infection rates amongst vaccinated groups mean vaccines are less effective than we hoped, especially in the face of the feared Delta variant.
Epidemiologist Dr Katelyn Jetelina from the University of Texas Health Science Centre School of Public Health explains why this isn’t what the numbers show – rather than decreasing vaccine effectiveness, increasing rates can be explained by a statistical phenomenon known as ‘base rate fallacy’.
Presenter: Charlotte McDonald
Producer: Nathan Gower
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- Sat 7 Aug 202104:50GMTBBC World Service except East Asia & South Asia
- Sun 8 Aug 202113:50GMTBBC World Service
- Sun 8 Aug 202121:50GMTBBC World Service except South Asia
- Mon 9 Aug 202109:50GMTBBC World Service
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