From the article:
“…two new studies published in the New England Journal of Medicine shed further light on the profound toll of COVID-19 on cognitive health.” And in other studies cases “with mild to moderate COVID-19 showed significant prolonged inflammation of the brain and changes that are commensurate with seven years of brain aging.”
Did they ask the exact same questions as before? If they did, it would probably skew the results. If they didn’t, it would also probably skew the results.