The First Twenty Years of the Will and the Ways: An Examination of Score Reliability Distribution on Snyder’s Dispositional Hope Scale

C. R. Snyder has established hope theory as an important contributor to positive psychology. As the empirical evidence continues to grow, hope researchers need to have confidence that their measures will produce reliable scores. This study presents a reliability generalization on both the internal consistency and test–retest reliability estimates from Snyder’s dispositional hope scale. While over 300 published works were found to have cited the target article 74 present internal consistency scores and 17 reported scores for test–retest reliability. The results of the reliability generalization suggest support for the score reliabilities produced by the dispositional hope scale. However, internal consistency was higher for studies using the eight-item response format (α = 0.82) compared to those using the four-item response format (α = 0.77). Additionally, the test–retest score reliability was high 0.80 with no statistically significant differences by response format. Findings also demonstrated that score reliability estimates were not significantly influenced by the coded sample characteristics.