Ugh, the famous NASA study that everyone loves to quotes and nobody ever reads :)
It’s freely available from the NASA website, and it looks like that Wikipedia page includes a link in the footnotes.
At the very least, skim through it: they chose the plants to test based on what they could find at a random garden shop in Mississippi. They didn’t use pots filled with dirt - they built their own pots that had electrically powered fans and ducts. There’s a drawing in the report, you can make your own!
It’s definitely good to have houseplants; the more the better! But this report isn’t really of much value to the average homeowner.