Degree Type


Date of Award


Degree Name

Doctor of Philosophy


Industrial Education and Technology

First Advisor

Dennis W. Field


The purpose of this study was to analyze the quality of the National Association of Industrial Technology (NAIT) certification examination quality control section, which contains forty items, using the methodologies of classical test theory (CTT) and item response theory (IRT). The ultimate goal of this research project is to evaluate the quality control portion of the NAIT certification exam by looking at the questions or items for errors. The project goal through this analysis was to identify the item problems and make recommendations to correct them.;The following conclusions were made based on a moderate sample of 996 examinees: (1) The test is still being developed. (a) The tests validity needs to be evaluated. (b) Objectives formulated need to be examined based on quality control. (2) Using classical test methodology, the test's reliability was originally.59. (a) It was improved to .74 by eliminating poor item discrimination questions. (3) Item response theory methodology revealed item characteristics that included: (a) Only a few items contributed to total test information results. (b) Item discrimination was considered to acceptable for approximately half of the items. (4) The examinee ability ratings mean was -0.0147 with a standard deviation of 1.15. (a) The correlation between examinee scores and their ability rating was .92. (5) The test was found to be unidimensional after removing the poor discriminating items.



Digital Repository @ Iowa State University,

Copyright Owner

Douglas Lyle McCue



Proquest ID


File Format


File Size

136 pages