Measuring religious identities in surveys

The purpose of this article is to acquaint the broader public opinion research audience with what has been a salient issue within the community of scholars of religion. We address the question of how best to conceptualize and measure religious identities in research on contemporary American society. We consider the main approaches to the measurement of religious identification with regard to their backgrounds, their assumptions about the importance of understanding religious identities in historically relevant terms, and the practical considerations of survey measurement. Using data from the General Social Survey, particularly recent innovative efforts to obtain information on subjective association with particular religious traditions and/or movements (e.g., Pentecostal, fundamentalist, evangelical, mainline, or liberal Protestant), we compare the two main approaches: the traditional "denominational" approach, where religious identities are assumed to be associated with religious denominations, and the subjective approach, where religious identities are assumed to be captured by a set of "nondenominational" reference categories linked to particular historical religious traditions or social movements. We conclude that both approaches have substantial predictive validity, and the most effective strategy for future research may be one that uses a combination of approaches, rather than one that relies entirely on a single method of measurement.