Development and Validation of a Training-Embedded Speaking Assessment Rating Scale: A Multifaceted Rasch Analysis in Speaking Assessment

Performance testing including the use of rating scales has become widespread in the evaluation of second/foreign oral language assessment. However, no study has used Multifaceted Rasch Measurement (MFRM) including the facets of test takers’ ability, raters’ severity, group expertise, and scale category, in one study. 20 EFL teachers scored the speaking performance of 200 test-takers prior and subsequent to a rater training program using an analytic rating scale consisting of fluency, grammar, vocabulary, intelligibility, cohesion, and comprehension categories. The outcome demonstrated that the categories were at different levels of difficulty even after the training program. However, this outcome by no means indicated the uselessness of the training program since data analysis reflected the constructive influence of training in providing enough consistency in raters’ rating of each category of the rating scale at the post-training phase. Such an outcome indicated that raters could discriminate the various categories of the rating scale. The outcomes also indicated that MFRM can result in enhancement in rater training and functionality validation of the rating scale descriptors. The training helped raters use the descriptors of the rating scale more efficiently of its various band descriptors resulting in a reduced halo effect. The findings conveyed that stakeholders had better establish training programs to assist raters in better use of the rating scale categories of various levels of difficulty in an appropriate way. Further research could be done to make a comparative analysis between the outcome of this study and the one using a holistic rating scale in oral assessment.