What does the term "true score" refer to in assessment?

The term "true score" refers to an individual's actual score on the variable being measured, reflecting the score one would obtain if there were no errors in measurement. This concept stems from classical test theory, which posits that an observed score is comprised of the true score plus some measurement error.

Understanding true score is crucial in assessment as it represents the most accurate reflection of a person's abilities or knowledge. It isolates the actual capability from any influences that might distort the measurement, such as testing conditions or the individual's emotional state on the day of testing. Therefore, option B accurately captures this definition, highlighting the focus on the inherent ability or attribute being evaluated rather than the fluctuation caused by external factors.

Other choices do not encapsulate the essence of true score. An individual's obtained score simply reflects what they scored, but this includes any errors. Predetermined criteria refer to the standards against which assessments are evaluated, and the amount of error in a measured score pertains to the discrepancies between observed scores and true scores but does not define what a true score is.