Computerized Dynamic Assessment (CDA), encouraged by Brown and colleagues’ graduated prompt approach, is grounded in Vygotsky’s Socio-Cultural Theory (SCT) of mind and its concept of the zone of proximal development (ZPD). It emerged to respond to the challenge of implementing DA in large classes and to meet the psychometric properties of assessment. To this end, the present study attempted to design a unique computerized dynamic assessment tool to diagnose learners’ development of pragmatic competence, specifically their knowledge of the speech acts of apology and request. To conduct the research, a number of 60 BSc students of engineering, aged 18-24, participated in the study. They had different proficiency levels, including pre-intermediate, intermediate and upper-intermediate levels. In the course of CDA, they were provided with 30 multiple choice discourse completion tests of apology and request and they were required to choose what they would say in that specific situation. The participants received pre-established meditational hints for each of the unacceptable responses, which were arranged from the most implicit to the most explicit. Finally, to diagnose learners’ development, their test performance, including their actual score, mediated score and learning potential score (LPS), was instantly displayed. Paired samples t-test showed development in learners’ mediated score. The results of the univariate analysis of variance showed that there is no interaction between mediation and proficiency level. Teachers can use this supplementary dynamic assessment tool to diagnose learners’ development of pragmatic competence.
