Construct validity refers to the degree to which a test or measurement accurately represents the theoretical concept it is intended to measure. It ensures that the tool effectively captures the underlying construct, such as intelligence or anxiety, rather than unrelated factors. To establish construct validity, researchers often use various methods, including factor analysis and correlation studies. These methods help demonstrate that the test correlates with other measures of the same construct and diverges from measures of different constructs, confirming its relevance and accuracy in assessing the intended concept.