"If it's difficult to believe that people embrace a flat Earth, it's going to be difficult to trust a poll that claims to validate that belief," wrote NCSE's Glenn Branch and Craig A. Foster of the US Air Force Academy in a blog post for Scientific American (October 24, 2018).
Continuing their previous discussion of what seems to have been the first systematic attempt to assess the American population's views on the shape of the Earth, Branch and Foster wrote, "readers of our previous column were skeptical of the poll's results — suspicious about the way in which the participants were selected, critical of the question used to assess belief about the shape of the Earth, and speculating about the possibility of insincerity skewing the outcome."
"There were genuine flaws in YouGov's poll, and there is clearly room for improvement," Branch and Foster concluded. But they added that the poll credibly indicates that belief in a flat Earth is present, if at a low level, in the American population.