Teachers must ensure that student assessments are valid and reliable to make fair evaluations. Validity refers to how well an assessment measures what it is intended to measure. There are several methods for establishing validity, including face validity which considers readability, content validity which examines how well content matches what is being tested, and construct validity which determines if the test covers the relevant behavior domain. Criterion-related validity compares test scores to external criteria and has two types: predictive validity which indicates how well scores predict future performance, and concurrent validity which shows how closely scores relate to other valid assessment measures.