What does validity of a test specifically measure?

The validity of a test specifically measures whether the test accurately assesses what it is intended to measure. For example, if a test is designed to evaluate a student's math skills, high validity means that the test effectively evaluates those specific skills rather than unrelated knowledge. Validity ensures that the inferences made from test scores are relevant and appropriate for the intended purpose, reflecting the true capabilities or knowledge of the test-taker regarding the subject matter.

Alternative concepts like consistency over time relate to reliability, which ensures that a test yields stable outcomes across different administrations. Comparing a test against a standard reference relates to criterion validity, while assessing the difficulty level of test items deals with the complexity and strain required to solve or answer them, rather than the accuracy of what the test measures. Thus, validity is crucial for establishing the relevance and accuracy of assessment tools in educational settings.