Despite the general criticisms of self-reports pointing out problems due to memory and cultural biases, self-reports remain a widespread method for assessing ritual attendance such as churchgoing. During an eight-month-long observation in a Fijian village, John Shaver, Thomas White, Patrick Vakaoti, and Martin Lang measured how self-report methods correlate with actual church attendance of the local population.
They found that self-report measures do not predict ritual attendance measured by observation and that people with parental duties were more likely to over-report their ritual attendance. Furthermore, the data suggested that third-part ratings of a person’s religiosity were the best predictor of that person’s frequency of ritual attendance.
You can find the article here:
https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0257160
Jana Nenadalová, Piotr Szymanek (Jagiellonian University), and Neil Van Leeuwen (Georgia State University) received a grant from the Open Science of Religion initiative (supported by the John Templeton Foundation) for a virtual reality study.
In his thesis, titled Costly signaling theory of pilgrimage: The case study of pilgrimage to Santiago de Compostela, he studied whether pilgrimages may function as costly signals of commitment to group norms.
