This graphic is an example of religion Gallup polls. In 2006, 2007, and 2008, representative samples in 143 countries and territories were asked whether religion was an important part of their daily lives. This map is based on the results, and shows religiosity by country, ranging from the least religious to the most religious on a relative basis. // graphic from Creative Commons user Sbw01f
Religious polling is facing the same loss of confidence from the public and other problems as polling in general, but surveys on religion may face particular challenges, writes sociologist Robert Wuthnow in First Things magazine (Aug./Sept.). In an article adapted from his forthcoming book on religion and polling, Wuthnow writes that religion polling’s use of a single method rather than multiple methods without extensive knowledge of religion itself has plagued the enterprise from its beginnings in the 1940s. There has been growing distrust of polling results, with public approval dropping from 80 percent in the 1980s to 34 percent in 2006. In a similar way, the response rates in polling have decreased significantly — from the 65 to 75 percent range in the 1980s to about 10 percent today. This is especially problematic since religion polling does not have the benchmarks used by political polling provided by election results. Wuthnow notes that those who tend to respond to surveys are also more likely to volunteer for other things as well.
Such responders are also more likely to attend religious services, to be evangelical Protestant, and to regard themselves as personally religious. This flaw in polling can cause serious inaccuracies in estimating church attendance. Gallup polls and similar surveys that have estimated attendance around 40 percent (100 million attendees) stand in contrast to academic surveys with good response rates, which find that the estimates are by about 30 million. When national surveys are inaccurate, regional polls are likely to be off the mark also. “Reporting that the population of one state is more religiously active than the population of another state, for example, is meaningless unless the bias from low response rates in the two states is known to be equal,” Wuthnow writes. Even the polling results about the growth of the non-affiliated may be missing a more important development: “The responses particular individuals give when pollsters call do not hold steady apart from minor incremental changes associated with aging or marriage…Between a third and a half of pollees give different responses a year later even to relatively straightforward questions about religious preferences and attendance.”
(First Things, 35 E. 21st St., Sixth Fl., New York, NY 10010)