I think the study is missing a condition. Both of the biographies they used suggest that the article was written by generic, if competent, journalist. Neither

I think the study is missing a condition. Both of the biographies they used suggest that the article was written by generic, if competent, journalist. Neither include details that might push you towards trusting this specific person. Since the test article was about a 'superbug', imagine one profile said "Jim completed a masters in immunology at Columbia University before moving to NYU'S Carter Journalism Institute." Without that, it's hard to know whether readers just ignore these blurbs altogether...