Which method is NOT commonly used to assess reliability?

The method identified here as the one that is not commonly used to assess reliability is indeed appropriate, as bivariate analysis primarily focuses on the relationship between two variables rather than on measuring the consistency of a specific measurement instrument. Reliability refers to the degree to which an assessment tool produces stable and consistent results over time.

In contrast, the test-retest method assesses reliability by measuring the same subjects at two different points in time and evaluating how similar the results are. The split-half method involves dividing a test into two halves and correlating the scores on each half to determine internal consistency. Using established measures refers to employing already validated instruments to ensure reliability based on prior evidence of consistency. Each of these methods directly addresses the degree of reliability of a measurement instrument, whereas bivariate analysis does not evaluate the reliability of a tool but rather explores patterns or correlations between two different variables.