What indicates whether a test measures what it claims to measure?

Validity is the key concept that indicates whether a test measures what it claims to measure. It assesses the degree to which evidence and theory support the interpretations of test scores for proposed uses of the test. In other words, a valid test accurately captures the construct it is intended to assess, ensuring the results are meaningful and applicable.

Consider the other concepts briefly: reliability refers to the consistency of the test results over time or across different populations. A test can be reliable but not valid; it may yield consistent results without actually measuring what it is supposed to measure. Fairness focuses on ensuring that test outcomes are not biased against any group and that individuals have an equal opportunity to perform. Standardization refers to administering and scoring a test in a consistent way to ensure uniform conditions across all test-takers. While these components contribute to the overall quality of a test, validity is specifically concerned with the accuracy of what the test is intended to measure.