Al-Hikmah University Journal

The research was conducted using a descriptive survey research design. The study's population were all Osun State senior secondary school three Physics students. Six hundred and thirty-one senior secondary school Physics students were chosen using a multistage sampling technique for the study sample. NECO 2018 physics practical examination was used to collect relevant data for the study. The -2loglikelihood chi-square value, Generalized Partial Credit Model, Standard Error of Estimate (SE), standardized fit index (Zh) and limited-information fit measure were used to analyze the collected data. The results showed that only five out of the 37 the tasks required to judge the proficiency of students in Physics practical were of adequate level of difficulty. However, 28 out of the 37 tasks required to judge the proficiency of students in Physics practical has high discrimination parameter estimates that were greater than the benchmark of 0.35. The result also showed that out of the 37 tasks used in assessing the proficiency of students in Physics practical by NECO, 34 items fitted the generalized partial credit model used in the calibration of the test. The study concluded that the psychometric properties of 2018 NECO physics practical examination items were adequate but with deficiency in the difficulty level. The study therefore concluded that information provided by IRT model on the estimates of the test were dependable and can be reliably used in the evaluation of the quality of Physics practical test items.