Although a small number of studies use longitudinal data, cross-sectional convenience samples are the most prevalent. Recent studies are beginning to use nationally representative data sets such as the National Education Longitudinal Study of 1988 and the National Longitudinal Study of Adolescent Health. Recent research has linked county-level data on current and historical religiosity and crime rates to explore the relationship between community religious membership and frequency of criminal acts such as murder, rape, larceny, and assault (Heaton, 2006).
The majority of studies on religion and crime use quantitative research or mixed methods that include both a quantitative and qualitative component. Most of these studies do not pay adequate attention to the direct and indirect effects of religiosity on crime and do not use random sampling or multiple indicators to control for measurement errors (Johnson, Larson, McCullough, 2000a). Recent research papers improve on these methods by testing causal models of the direct and indirect effects of religiosity as a protective or a risk factor (Jang & Johnson, 2008) as well as addressing selection issues using an instrumental variables approach (Heaton, 2006).
Religious measures have been used in a variety of ways in research exploring crime and religion. The number of factors used to measure religion is also important. In a systematic review of the religiosity and delinquency literature, Johnson and colleagues (2000) found that the majority of studies measure religiosity with a single-item measure, and this item is usually church attendance. When considering the dimensions of religious measures, six categories are typically used. These include:
- Attendance how often participants attend religious services;
- Salience the importance of religion in participants lives;
- Denomination denominational affiliation of the participants;
- Prayer the degree to which participants indicate that prayer is an active or meaningful part of their lives;
- Bible study the tendency to participate in the independent study of sacred texts; and
- Religious activities participation in religious activities both in and out of typical church settings.