Word Play – Raw Scores vs. Scaled Scores
Test scores convey performance on a test to candidates. Scores are usually reported as either a raw score or a scaled score.
A raw score is a score that represents the total number of items on an exam that a candidate has answered correctly. Raw scores are easily interpreted by candidates and provide clarity, meaningful feedback, and transparency. Scaled scores are used to report performance on an exam on a consistent scale. They are calculated by using statistical methodologies to adjust and convert raw scores onto a common scale. Scaled scores take into account the differences in difficulty between the forms and allow scores on different forms of the exam to be comparable.
For example, consider an exam that reports scores on a scale of 200 – 800 with 500 as the passing score. If Form A of the exam is slightly more difficult than Form B of the exam, a process of equating can be used to determine equivalency of scores. A passing score of 64 on Form A may be equivalent to a 67 on Form B. Raw scores on both forms can be converted across a common scale so that the two equivalent scores will be reported to candidates as the same scaled score of 500.