January 14, 2021

Measuring Religion in Pew Research Center’s American Trends Panel

Methodology

The data in this report comes mainly from three different sources: The aggregated set of all of the random-digit dial (RDD) telephone surveys the Center conducted between January 2019 and July 2020; the annual profile survey (conducted Aug. 3 to 16, 2020) the Center administers to respondents in its American Trends Panel (ATP), which is an online survey panel recruited through national, random sampling of residential addresses; and the 2020 National Public Opinion Reference Survey (NPORS), conducted online and by mail June 1 to Aug. 11, 2020.

Details about how the Center conducts its RDD telephone surveys is available here. Specific information about how the March 20 to 25, 2019, RDD survey was conducted is available here.

Details about methods used for ATP surveys are available here.

Details about how the NPORS was conducted are available here.

The complete text of the wording of the questions analyzed in this report is available in the questionnaire.

The following table shows the unweighted sample sizes and the error attributable to sampling that would be expected at the 95% level of confidence for the data sources analyzed here:

In addition to sampling error, one should bear in mind that question wording and practical difficulties in conducting surveys can introduce error or bias into the findings of opinion polls.

Pew Research Center undertakes all polling activity, including calls to mobile telephone numbers, in compliance with the Telephone Consumer Protection Act and other applicable laws.

Pew Research Center is a nonprofit, tax-exempt 501(c)(3) organization and a subsidiary of The Pew Charitable Trusts, its primary funder.