Anxiety is one of the most pervasive symptoms seen in clinical psychological disorders. The Beck Anxiety Inventory (BAI) is a popular measure to assess the construct of anxiety. This study was concerned with an examination of potential study factors that are associated with the variability of the reliability estimates of the BAI scores. A review of the literature involving the BAI showed that more than 57% of the publications either did not mention reliability estimates for BAI scores or presented secondary reliability estimates. This meta-analysis of coefficient alpha and test-retest reliability estimates showed that diagnostic classification of participants and the within-study BAI score variability were related to the magnitude of the reliability estimates.