There are many reasons that will determine whether a test is valid or invalid. Most importantly is test reliability. If the test yields inconsistent scores—when it is repeated many times and scores vary widely it is considered invalid. Secondly, the person taking the test may slant their answers in a particular way for any number of reasons, whic include: inclination for the person taking the test to say “yes” or agree to most of the questions, but the person also may not understandwhat is being asked; the person taking the test answers questions in suc a way that they will look good; the person taking the test says “no” or answers to look bad intentionally for reasons suc as getting some kind of compensation.

Cultural bias will invalidate a test if the questions do not have the same meaning across cultures. Face validity, the actual content of the test, may have different meanings to people from other cultures. Bias in the test will occur if the test is measuring a specific quality and the test content is slanted to favor one group over another, suc as racial and gender differences. Many tests measure future performance (predictive validity), and experts believe that many tests inaccurately assess performance for minority groups and women. The reasons given for invalidity are also ones that many critics of standardized tests give in their arguments against psycological testing.