An Empirical Comparison of Four Generalized Trust Scales: Test–Retest Reliability, Measurement Invariance, Predictive Validity, and Replicability

The Stranger Face Trust scale (SFT) and Imaginary Stranger Trust scale (IST) are two new self-report measures of generalized trust that assess trust in strangers—both real and imaginary—across four trust domains. Prior research has established the reliability and validity of SFT and IST, but a number of measurement validation tests remain. Across three separate studies, I assess the test–retest reliability, measurement invariance, predictive validity, and replicability of SFT and IST, with the misanthropy scale (MST) and generalized social trust scale (GST) serving as benchmarks. First, tests of internal consistency, test–retest reliability, and longitudinal measurement invariance established that all four generalized trust scales were acceptably reliable, with SFT and IST yielding greater overall reliability than MST and GST. Second, tests of multiple group measurement invariance revealed that SFT and IST were equivalent across gender, race, education, and age groups, while MST and GST were non-equivalent across the same sociodemographic groups. Third, an investment game established the predictive validity of SFT and MST, with IST and GST yielding poor predictive validity. Fourth, tests of factor structure and measurement invariance indicated that all four generalized trust scales replicated across samples. The present findings bolster the validity, reliability, and measurement equivalence of SFT and IST, while illustrating the compromised validity and measurement non-equivalence of MST and GST. Implications for the measurement of generalized trust are discussed.