A new PRRI study, “I Know What You Did Last Sunday: Measuring Social Desirability Bias in Self-Reported Religious Behavior, Belief, and Belonging,” asked random samples of Americans identical questions about religious attendance, affiliation, salience and belief in God on two surveys – one via telephone and the other online – and compared the results. The research shows that every subgroup of Americans inflates their levels of religious participation, with young adults, Catholics and white mainline Protestants particularly likely to inflate the frequency of their attendance at religious services.
Among the findings:
- On the telephone survey, 36 percent of Americans report attending religious services weekly or more, compared to 31 percent on the online survey.
- Compared to 30 percent of telephone respondents, 43 percent of online survey respondents say they attend religious services seldom or never.
- When interviewed by telephone, fewer than 3-in-10 (29 percent) white mainline Protestants report that they seldom or never attend religious services, compared to 45 percent of white mainline Protestants who took the self-administered online survey.
- Catholics are less than half as likely to report seldom or never attending religious services when responding on the telephone versus online (15 percent vs. 33 percent).
- Nine percent of white evangelical Protestants report they seldom or never attend religious services when speaking with an interviewer by phone, compared to 17 percent who report the same in a self-administered online survey.
- Only 14 percent of black Protestants report seldom or never attending on a telephone survey, compared to nearly one-quarter (24 percent) on the online survey.
- Surprisingly, the social desirability effects are strong among the religiously unaffiliated. While 73 percent say they seldom or never attend religious services in a telephone survey, that number jumps nearly 20 percentage points to 91 percent on an online survey.
- The study also found significant differences between younger and older Americans, as well as among different regions of the country, in the degree to which they inflate religious participation.