A reliability generalization meta-analysis of coefficient alpha and test-retest coefficient for the aging males' symptoms (AMS) scale.

PURPOSE: The aging males' symptoms (AMS) scale is an instrument used to determine the health-related quality of life in adult and elderly men. The purpose of this study was to synthesize internal consistency (Cronbach's alpha) and test-retest reliability for the AMS scale and its three subscales. METHODS: Of the 123 studies reviewed, 12 provided alpha coefficients which were then used in the meta-analyses of internal consistency. Seven of the 12 included studies provided test-retest coefficients, and these were used in the meta-analyses of test-retest reliability. RESULTS: The AMS scale had excellent internal consistency [α = 0.89 (95% CI 0.88-0.90)]; the mean alpha estimates across the AMS subscales ranged from 0.79 to 0.82. The AMS scale also had good test-retest reliability [r = 0.85 (95% CI 0.82-0.88]; the test-retest reliability coefficients of the AMS subscales ranged from 0.76 to 0.83. There was significant heterogeneity among the included studies. CONCLUSIONS: The AMS scale and the three subscales had fairly good internal consistency and test-retest reliability. Future psychometric studies of the AMS scale should report important characteristics of the participants, details of item scores, and test-retest reliability.