What does test-retest reliability assess?

Test-retest reliability assesses the consistency of a test over time. This concept is fundamental in measurement, as it evaluates whether a test produces stable and consistent results when the same individuals are tested multiple times under similar conditions. If a test has high test-retest reliability, it indicates that the test yields similar outcomes regardless of when it is administered, provided the condition being measured hasn’t changed.

This reliability is important in occupational therapy practice because it ensures that the results obtained from assessments are dependable over time. For instance, if an occupational therapist uses a particular assessment tool to determine a client's level of functioning and then administers the same tool again after a certain period, the expectation is that the scores should be similar if the client's functioning has not significantly changed. Consistent scores reinforce the credibility of the assessment results and aid in monitoring progress accurately.

Other options, while related to assessment and measurement, do not specifically focus on the aspect of consistency over time. They address different facets of testing, such as accuracy, variability, or validity, which are important in their own rights but do not capture the essence of what test-retest reliability evaluates.