What defines a written test that has reliability?

A written test exhibits reliability when it yields consistent results across different administrations, or when it is taken by different groups of people under similar conditions. This means that if the same test is administered multiple times to the same group, or if it is given to different groups that are comparable in ability, the scores should reflect similar outcomes. Consistency in results indicates that the test measures the same construct each time, regardless of external factors that might influence performance, such as the time of day or the specific setting in which the test takes place.

Other factors, like visual appeal or extensive subject coverage, may contribute to a test's effectiveness or validity but do not necessarily speak to its reliability. Grading by multiple instructors can help reduce bias in evaluation, but it does not guarantee that the test itself is designed to produce consistent results across varying contexts. Therefore, a test's reliability fundamentally revolves around its ability to provide stable and uniform scores under similar circumstances.