Community Notes, which allows users to contribute notes that add context or corrections to posts, was introduced by X in late 2022 and the same model is increasingly being adopted by other tech platforms.
But researchers have repeatedly questioned its effectiveness in combating misinformation.
NewsGuard, a US watchdog that rates the credibility of news and information sites, identified dozens of posts on X that advanced false claims related to the elections, including bogus allegations of election fraud.
Only 13 of those posts were tagged with Community Notes.
"X's crowdsourced fact-checking program failed to flag 93.1 percent of false claims related to the US midterm elections," NewsGuard said.
"The uncorrected X posts have drawn millions of interactions ahead of the November 3 midterm elections."
The falsehoods included a post by a conservative commentator claiming that New York and California had made it illegal for voters to show -- and officials to ask for -- their voter ID. No such rule exists in either Democratic stronghold.
Musk has often promoted Community Notes, calling it "awesome" and asserting that all users, including himself, were subject to being corrected by the crowd-sourced model.
NewsGuard, however, said that Musk, who has 241.5 million followers on X, has advanced at least four false claims related to the midterm elections, none of which carried Community Notes.
X did not respond to AFP's request for comment.
Studies have shown Community Notes can...
Community Notes, which allows users to contribute notes that add context or corrections to posts, was introduced by X in late 2022 and the same model is increasingly being adopted by other tech pl...