Demonstrating the Difference between Classical Test Theory and Item Response Theory Using Empirical Data: Implication for Educational Research

The study demonstrated by determining among others the reliability; mean score difference between male and female candidates in 2019/2020 Katsina State BECE in mathematics scores/items using CTT and IRT. Expose facto design was used for the study. The population of the study consisted of 65,797 (42,110 male and 23,687 female) candidates. A multi-stage stratified random sampling technique was used to select 500(290 male and 210 female) candidates. Data for the study was obtained from the KSERC Examination Officer. Hypotheses were tested at = 0.05 level of significance. The data were analyzed using SPSS and WINSTEPS version 4.8.2.0 software. Some of the findings from the study revealed a reliability coefficient of 0.99 using both CCT and IRT; it is a statistically significant (t = 5.663, df = 449, p = 0.000) difference between the mean score of male and female candidates; and 57% (34) of the BECE Items in Mathematics have different difficulty levels for male and female candidates. Implications from the findings for educational research were also discussed. A similar study in a different field to determine the possibility or otherwise of combined CTT and IRT analysis was the recommendation made from the study.