Do Thi Ha, HCMC University of Technology and Education, Vietnam; University of Technology, Sydney
The Implementation of Testlet Models into Evaluating a Reading Comprehension Test

Testlets, groups of test items that share the common input, are widely used in language testing. However, there lies a problem of Local Item Dependence (LID) which may result in adverse consequences for test score perception. This study analyzed the reading comprehension section of an English multiple-choice test to determine whether, and to what extent, testlet effects are inherent by using Testlet Response Theory (TRT). The data was gathered from 1653 non-English majors taking that final test at a university in Vietnam. The comparison of item difficulty and discrimination between Testlet Response model and Item Response Theory (IRT) model was made to illustrate the testlet effects. The paper, therefore, demonstrated how these models can be utilized into the test development process so that test developers can choose the best-fitting model and minimize inaccuracies of ability estimation.

Do Thi Ha has worked as a lecturer at HCMC University of Technology and Education in Vietnam. She is currently doing her PhD at University of Technology, Sydney in Australia. Her research interests lie in Motivation, Language Testing and CALL.