When are fact-checks effective? An experimental study on the inclusion of the misinformation source and the source of fact-checks in 16 European countries

Despite increasing academic attention, several questions about fact-checking remain unanswered. First, it remains unclear to what extent fact-checks are effective across different political and media contexts. Second, we know little on whether features of the fact-check itself influence its success. Conducting an experiment in 16 European countries, this study aims to fill these gaps by examining two features of fact-checks that may affect their success: whether fact-checks include the political source of the misinformation, and the source of the fact-check itself. We find that fact-checks are successful in debunking misperceptions. Moreover, this debunking effect is consistent across countries. Looking at features of fact-checks, we find no indication that it matters whether fact-checks include the political source of the misinformation claim. Comparing fact-checks from independent organizations with those from public broadcasters, we do find, however, that who the fact-checker is matters, especially in combination with trust in this source.