A behind-the-scenes blog about research methods at Pew Research Center. For our latest findings, visit pewresearch.org. Pew Research Center sometimes employs cognitive interviewing to help improve ...

During an interview set to air Thursday, former Vice President Joe Biden said that he had not taken a cognitive test and attacked the question as unfair, likening it to being asked if he was a “junkie ...

The president again tried to defend his own mental fitness for office — and disparage Joe Biden’s — by frequently repeating a memory sequence: “Person. Woman. Man. Camera. TV.” By Katie Rogers ...

Former U.S. Ambassador to the United Nations Nikki Haley suggested in an interview on Thursday that leaders in the government who are of an advanced age should undergo a “cognitive test.” The ...