Sciencenorway.no and several other media outlets wrote that the study showed that people who have had Covid-19 have a poorer memory than people who have not had it.
But is this correct?
“The way newspapers, including both journalists and the research team, have interpreted the study does not hold up,” says [Christoffer] Olsen, who researches medical statistics at Oslo University Hospital (OUS).
The findings of the study could be attributed to factors other than the infection itself.
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Those who have tested positive for Covid-19 may simply perceive their own memory to be worse than it actually is.
“When you know you’ve had Covid-19 and have heard all the talk about brain fog, you might respond a bit differently than if you haven’t had it, but have had the exact same symptoms,” Olsen explains.
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“If it had been completely random who did or did not respond, then it would have been a representative sample. But if it’s the case that those who have had Covid-19 and are experiencing brain fog respond more often, then there will be a bias,” Olsen says.
The researchers behind the study have mentioned these two weaknesses in the original study, but the caveat has disappeared in the media’s reporting of the findings, the statistician points out.
