From my new Monkey Cage post (co-authored with Yusaku Horiuchi):

State-sponsored propaganda like the recently unmasked @TEN_GOP Twitter account is of very real concern for our democracy. But we should not allow the debate over Russian interference to crowd out concerns about homegrown misinformation, which was vastly more prevalent during and after the 2016 election…

One promising approach [to countering misinformation] is summary fact-checking — an increasingly popular format that presents an overview of fact-checking ratings for a politician. This is distinct from focusing on whether a single statement is true or false; rather, it evaluates a group of such statements, assessing a speaker’s overall truthfulness and reliability as a source. Though the statements in question are of course not randomly chosen, the format may be an effective way to increase the costs of repeatedly making false statements.

One of us (Nyhan) investigated the effect of this format in three experimental studies conducted in 2016 and 2017 in collaboration with different undergraduate co-authors at Dartmouth.