Which statement best describes Reliability in testing?

• A. The degree to which a test measures different constructs
• B. How dependable or consistent a test is
• C. The difference between observed and true scores
• D. The speed at which a test is administered

Answer: (B)

Reliability is about consistency and dependability of test scores across occasions, forms, or scorers. A reliable test yields similar results under consistent conditions; the same person would score similarly if retested, different items measuring the same trait agree with each other, and scorers apply scoring rules consistently. Reliability doesn’t address whether the test measures what it intends (that’s validity); it focuses on stability and repeatability despite random error. The idea of a difference between observed and true scores relates to measurement error that reliability must contend with, but the core is the dependable, repeatable nature of the results. Options about speed of administration or about measuring different constructs pertain to other properties, not reliability.