Abstract
In this systematic review and meta-analysis, researchers' operationalizations of romantic infidelity and the techniques that they employed to measure it were surveyed along with the demographic characteristics of their respondent samples. A meta-analytic synthesis of infidelity prevalence estimates and their moderators is provided. The APA PsycINFO, PubMed, ISI Web of Science, and ERIC databases were searched for peer-reviewed, English-language studies reporting infidelity prevalence rates that were published as of September 2022. Weighted aggregate estimates of different forms of infidelity were calculated and the moderating effects of certain methodological variables on these estimates were examined. Study-level risk of bias was assessed using the Appraisal tool for Cross-Sectional Studies (AXIS). A total of 305 studies met the inclusion criteria, with an aggregate sample size of 508,241 respondents across 47 countries. Multiple forms of infidelity were identified, with sexual infidelity receiving the most research attention and many studies lacking clear infidelity operationalization. Anonymous data collection and convenience sampling were found to result in greater report of sexual, but not emotional, infidelity. The findings indicate that nonsexual forms of infidelity remain underexplored. Additionally, operational ambiguity and sample demographic homogeneity are widespread in the existing infidelity research literature. Research practices in this field raise concern regarding the effects of impression management, self-selection, and response biases.