Certified Rehabilitation Counselor Practice

What does test retest reliability measure?

1. Internal consistency

2. Consistency over time

3. Content representation

4. Item correlation

The correct answer is: Consistency over time

Test-retest reliability measures the consistency of a test over time. This concept entails administering the same test to the same group of individuals on two different occasions and then comparing the scores obtained from both administrations. If the scores are similar, it indicates that the test produces stable and reliable results, suggesting that the construct being measured is consistent over time. This is particularly important in various fields, including psychology and education, where stable measures are crucial for assessing changes or outcomes. For example, if a psychological assessment yields significantly different results on repeated administrations without any real change in the individual's state, the reliability of that test could be questioned. Other options address different aspects of reliability or test development: internal consistency pertains to how well the items on a test measure the same construct, content representation focuses on how well the test encompasses the full domain of the subject being assessed, and item correlation refers to the degree to which responses to individual test items relate to each other. Each of these is important in its own right but does not capture the temporal aspect that test-retest reliability focuses on.