U.S. Religious Landscape Survey - Continental Dataset

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The U.S. Religious Landscape Survey completed telephone interviews with a nationally representative sample of 35,556 adults living in continental United States households. The survey was conducted by Princeton Survey Research Associates International (PSRAI). This extensive survey by the Pew Forum on Religion & Public Life details the religious makeup, religious beliefs and practices as well as social and political attitudes of the American public.

Information on this page was adapted from the Pew Forum's methodology report for this survey.

Data File
Cases: 35,556
Variables: 133
Weight Variable: WEIGHT
Data Collection
Date Collected: May 8 - August 17, 2007
Funded By
Pew Forum on Religion & Public Life
Collection Procedures
The U.S. Religious Landscape Survey included telephone interviews with a nationally representative sample of 35,556 adults living in continental United States telephone households. The survey was conducted by Princeton Survey Research Associates International (PSRAI). Interviews were done in English and Spanish by Princeton Data Source, LLC (PDS), and Schulman, Ronca and Bucuvalas, Inc. (SRBI), from May 8 to Aug. 13, 2007. Statistical results are weighted to correct known demographic discrepancies.

As many as 10 attempts were made to contact every sampled telephone number. Calls were staggered over times of day and days of the week to maximize the chance of making contact with potential respondents. Each household received at least one daytime call in an attempt to find someone at home. Calling procedures and sample management were kept as consistent as possible between two phone rooms.

In each contacted household, interviewers asked to speak with the youngest adult male currently at home. If no male was available, interviewers asked to speak with the youngest adult female at home. This systematic respondent selection technique has been shown to produce samples that closely mirror the population in terms of age and gender.

For each contacted household in the callback sample, interviewers first identified the person who was previously contacted when he or she was screened out of the Muslim American survey sample. Then the respondent was asked screening questions to verify his or her religious affiliation. Once the respondent’s religion was confirmed as Buddhist, Hindu or Orthodox Christian, the full interview was administered, including an abbreviated battery of religious affiliation questions. As many as 10 attempts were made to contact every sampled telephone number. Calls were staggered over times of day and days of the week to maximize the chance of making contact with potential respondents. Each household received at least one daytime call in an attempt to find someone at home. Calling procedures and sample management were kept as consistent as possible between two phone rooms.

In each contacted household, interviewers asked to speak with the youngest adult male currently at home. If no male was available, interviewers asked to speak with the youngest adult female at home. This systematic respondent selection technique has been shown to produce samples that closely mirror the population in terms of age and gender.

For each contacted household in the callback sample, interviewers first identified the person who was previously contacted when he or she was screened out of the Muslim American survey sample. Then the respondent was asked screening questions to verify his or her religious affiliation. Once the respondent’s religion was confirmed as Buddhist, Hindu or Orthodox Christian, the full interview was administered, including an abbreviated battery of religious affiliation questions.
Sampling Procedures
The vast majority of the interviews (n=35,009) came from standard list-assisted random digit dialing (RDD) sample. This sample was provided by Survey Sampling International, LLC, according to PSRAI specifications. Active blocks of telephone numbers (area code + exchange + two-digit block number) that contained three or more residential directory listings were equally likely to be selected; after selection, two more digits were added randomly to complete the number. This method guaranteed coverage of every assigned phone number regardless of whether that number was directory listed, purposely unlisted or too new to be listed. After selection, the numbers were compared against business directories and matching numbers were purged.

To supplement the RDD interviews, an additional 547 interviews were completed from households that were initially contacted and screened out during data collection for the Pew Research Center’s survey of Muslim Americans that was released in May 2007. Specifically, households that were identified as being Hindu, Buddhist or Orthodox Christian were recontacted. This helped boost the sample size of these low-incidence groups. All the callback interviewing was conducted at PDS.
Principal Investigators
Pew Forum on Religion & Public Life
Weighting
Weighting is generally used in survey analysis to adjust for effects of the sample design and to compensate for patterns of nonresponse that might bias results. The weighting for the Landscape Survey was accomplished in two stages. The first stage of weighting corrected for two disproportionate sample elements. First, it corrected for the fact that the original sample used for the Pew Research Center’s Muslim American survey, from which the callback sample was pulled, overrepresented some parts of the country and underrepresented other parts. Second, it corrected for the oversampling of Buddhists, Hindus and Orthodox Christians.

After the first stage of weighting, the sample demographics were balanced to match national population parameters for sex, age, education, race, Hispanic origin, region, country of birth (for Latinos) and population density. These parameters came from a special analysis of the U.S. Census Bureau’s 2006 Annual Social and Economic Supplement, which included all households in the continental United States that had a telephone.

The second stage of weighting was accomplished using Sample Balancing, a special iterative sample weighting program that simultaneously balances the distributions of all variables using a statistical technique called the Deming Algorithm. Weights were trimmed to prevent individual interviews from having too much influence on the final results. The use of these weights in statistical analysis ensures that the demographic characteristics of the sample closely approximate the demographic characteristics of the national population.
Response Rate
The response rate estimates the fraction of all eligible respondents in the sample that were ultimately interviewed. PSRAI calculated it by taking the product of three component rates:

1. Contact rate – the proportion of working numbers where a request for interview was made – of 80 percent

2. Cooperation rate – the proportion of contacted numbers where a consent for interview was at least initially obtained, versus those refused – of 35 percent

3. Completion rate – the proportion of initially cooperating and eligible interviews that were completed – of 86 percent

Thus the response rate for this survey was 24 percent.