Validation of Test Construction Skills Inventory through the lens of Item Response Theory (IRT)
Keywords:Item response theory, 3-parameter logistic model, Test construction skills, Test of maximal/optimal performance, Test construction skill inventory, Likert-type scale.
The Item Response Theory (IRT) examines how testees at different ability levels respond to an item. The theory assumes that latent traits that are fewer in number than the test items account for responses to the items. This study validated the test construction skills inventory through the lens of IRT. Also, the study assessed teachers’ level of skills in test construction. The descriptive survey design was employed for the study. Using the cluster sampling, 583 senior high school teachers in the Cape Coast Metropolis were engaged in the study. The 3-parameter logistic model (3-PLM) through the IRTPRO software was used to validate the test construction skills inventory. Eighteen out of 25 items were deemed valid and used to assess teachers’ skills in test construction. It was found that the majority of the teachers had higher skills in test construction. Recommendations were made to the Ministry of Education, Ghana (MoE), Ghana Education Service (GES), and heads of the various SHSs in the Cape Coast Metropolis.