Certification

There are three scales in the above example. The raw items scale is the actual number of test items that the candidate must answer to pass. The percentage scale is the raw scale converted to a percentage of the exam that the candidate must answer correctly to pass. And the scale score scale is the scale where the passing score has been converted to another number. To use the scale, let’s say a candidate must answer 87 of 135 test items correctly to pass the exam. This converts to a percentage score of 65%. SCSA would scale that number to a 70. Every score above and below the passing score would also be scaled similarly to a Fahrenheit and Celsius scale.

To pass the SCSA examination, the candidate must obtain a scaled score of 70. The actual passing score (raw score and percent score) was determined using a passing score study on a single form of the examination. The passing score study looked at the characteristics of the examination (such as the difficulty of the test items) and used the methodologies of Angoff and Hofstee in a facilitate group meeting, to establish what the point at which the group of experts felt a score higher would represent knowledge to be competent and a score lower would represent a lack of knowledge to be competent. Subsequent forms of the examination are statistically equated to the first form and the raw score necessary to pass adjusted as necessary.