CHES Exam Background and Scoring
The CHES exam is a criterion-referenced test. The criteria are a set score for passing the test as determined by NCHEC. The set score, or standard, represents a fixed standard of knowledge and is independent of candidate performance on the test. The passing point or passing score is set using the modified Angoff method; the most widely used criterion-referenced technique in the credentialing community. It is based on the judgments of content experts regarding the expected test performance of candidates who are minimally competent.
Determining the Passing Point on the CHES Exam
The passing point is determined using a variety of statistical techniques which take into account item difficulty. The passing point is reviewed and extensive statistics are computed and analyzed for every CHES exam.
Reliability and Validity of the CHES Exam
Extensive test statistics are calculated in the process of determining test reliability and validity, including item analysis for every test item on the CHES exam. Reliability is determined by using the Kuder-Richardson Formula 20 and split half reliability. Reliability coefficients above 0.80 are considered satisfactory for credentialing exams. The CHES exam reliability coefficient, as determined by the K-R 20 and split-half methods, has consistently met or exceeded the standard over the years.
| Number of Items |
150 |
150 |
| Pass Point |
94 |
95 |
| Average Raw Score |
106.79 |
109.62 |
| Standard Deviation |
16.72 |
16.98 |
| Range of Raw Scores |
52-141 |
49-142 |
| Average Percent Score |
71.19 |
73.08 |
| Number of Candidates |
890 |
526 |
| Number of Candidates who passed (pass rate) |
700 (78.7%) |
417 (79.3%) |
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