Religion as a domain of exposure assessment in epidemiologic studies: History, meaning, and implications

For over a century, research findings have accumulated linking measures of religious identity and practice to rates of morbidity and mortality and other population-health outcomes. These studies have been conducted on every continent, have drawn on population samples of nearly all major religions and denominations, and have investigated associations with numerous overall and cause-specific rates of most major chronic diseases and acute conditions, both physical and psychiatric. Yet despite thousands of published studies and many comprehensive reviews, relatively less attention has been paid to conceptual, theoretical, and policy-related issues, notably what these studies are actually assessing, what resultant findings mean and do not mean, and why they should matter. This has contributed, in part, to the continued contentiousness of this subject within some segments of medicine and epidemiology. In an effort to clarify issues, this commentary outlines (a) the current status of exposure assessment related to religion; (b) the ways that the meaning of empirical findings are occasionally misjudged; (c) possible mediators of putative religious influences on morbidity and mortality; and (d) policy implications of existing findings. The latter includes implications for epidemiologic and population-health research, for clinical medicine, for congregational health promotion and disease prevention programs, for global health development and public health policy, and for human flourishing. In sum, this area of research can make a worthwhile contribution, but the burden is on investigators to ensure that their religious measures are validated and that findings are carefully unpacked in terms of their real-world implications for population health.