The degree to which a test measures what it is intended to measure and nothing else and is supported by evidence is called:

The degree to which a test measures what it is intended to measure and nothing else and is supported by evidence is called: Options: (a) Reliability (b) The confidence interval (c) Validity (d) Standard error of measurement ✅ Correct Option: (c) Validity Explanation (200+ words): Validity refers to the extent to which a test accurately measures what it is designed to measure and does not measure irrelevant factors. It is one of the most fundamental concepts in educational assessment. A test may be reliable (i.e., give consistent results), but it is not necessarily valid. For example, if a mathematics test consistently measures reading ability instead of math skills, it is reliable but invalid. Validity is not a single property of a test; rather, it is supported by evidence. This evidence can be content-related, criterion-related, or construct-related. Content validity ensures that the test items adequately cover the subject matter. Criterion-related validity examines how well test scores relate to an external criterion, such as future performance. Construct validity determines whether the test truly measures an abstract trait like intelligence or motivation. In educational testing, validity ensures fairness, accuracy, and meaningful interpretation of scores. Without validity, test results can mislead teachers, students, and policymakers, resulting in poor educational decisions. Therefore, validity is always a primary concern in test development, classroom assessment, and standardized testing systems. 10 Related PPSC Facts: Validity answers the question: Does the test measure what it claims to measure? Reliability is a prerequisite for validity. Content validity is ensured through a table of specifications. Criterion validity includes predictive and concurrent validity. Construct validity is the most comprehensive type. A valid test reduces assessment bias. Validity is evidence-based, not absolute. Teacher-made tests must ensure content validity. Standardized tests require extensive validity studies. Invalid tests lead to unfair educational decisions.