Why is important to maintain an assessment’s validity, reliability, and equity in testing?

Why is important to maintain an assessment’s validity, reliability, and equity in testing?

Reliability refers to the degree to which scores from a particular test are consistent from one use of the test to the next. ... Ultimately then, validity is of paramount importance because it refers to the degree to which a resulting score can be used to make meaningful and useful inferences about the test taker

4, -4 is the other point it would pass through