Test-Retest Reliability Behavior Rating Profile
Test-retest reliability measures the stability of test scores over time. To estimate this type of reliability, a test is administered twice to a group of examinees-generally with a week or two between the two administrations. The degree of reliability is usually expressed with a correlation coefficient. Note that when a correlation coefficient is used to describe reliability, it is called a "reliability coefficient," or, in this case, a "test-retest reliability coefficient." See Appendix A to review the correlation coefficient before attempting this exercise.