Comparative analysis of classical test theory and item response theory using chemistry test data

Abstract

Assessment of learning involves deciding whether or not the content and objectives of education are down pat by administering quality tests. This study assesses the standard of Chemistry action take a look at and compares the item statistics generated mistreatment CTT and IRT strategies. A descriptive survey was adopted involving a sample of N=530 students. The specialised XCALIBRE 4 and ITEMAN 4 softwares were used to conduct the item analysis. Results indicate that, both the two methods commonly identified 13(32.5%) items as “problematic” and 27(67.5%) were “good”. Similarly, a significantly higher correlation exists between item statistics derived from the CTT and IRT models, [(r=-0.985,) and (r=0.801) p<0.05] for item difficulty and discrimination respectively; the study concludes that the Chemistry Achievement test used do not pass through the processes of standardisation. Secondly, CTT and IRT frameworks appeared to be effective and reliable in assessing test items as the two frameworks provide similar and comparable results. The study recommends that the teacher made Chemistry tests used in measuring students' achievement should be made to pass through all the processes of standardisation. Meanwhile, CTT and IRT approaches of item analysis ought to be integrated within the aspects of item development and analysis because of their superiority within the investigation of reliability and minimising measurement errors.