Comparing Analysis Blinding With Preregistration in the Many-Analysts Religion Project

In psychology, preregistration is the most widely used method to ensure the confirmatory status of analyses. However, the method has disadvantages: Not only is it perceived as effortful and time-consuming, but reasonable deviations from the analysis plan demote the status of the study to exploratory. An alternative to preregistration is analysis blinding, in which researchers develop their analysis on an altered version of the data. In this experimental study, we compare the reported efficiency and convenience of the two methods in the context of the Many-Analysts Religion Project. In this project, 120 teams answered the same research questions on the same data set, either preregistering their analysis (n = 61) or using analysis blinding (n = 59). Our results provide strong evidence (Bayes factor [BF] = 71.40) for the hypothesis that analysis blinding leads to fewer deviations from the analysis plan, and if teams deviated, they did so on fewer aspects. Contrary to our hypothesis, we found strong evidence (BF = 13.19) that both methods required approximately the same amount of time. Finally, we found no and moderate evidence on whether analysis blinding was perceived as less effortful and frustrating, respectively. We conclude that analysis blinding does not mean less work, but researchers can still benefit from the method because they can plan more appropriate analyses from which they deviate less frequently.