The roles of suprasegmental features in assessing paired speaking tasks in high-stakes language assessment

In the realm of language assessment, the speaking abilities of second language (L2) speakers in communicative contexts have garnered increasing attention, as English serves as a lingua franca in our globalized world. In oral communication, suprasegmental features play a crucial role in shaping interactions. However, our comprehension of how proficient L2 speakers employ these suprasegmentals, particularly in the context of assessment, has been limited. This study investigated the utilization of suprasegmental features by L2 speakers, namely rate, pause, prominence, and pitch, to construct interactions and examined their connection to paired performance in a high-stakes oral assessment. This assessment is evaluated based on five criteria: Sensitivity to Situation, Language Use, Content Delivery, Discourse Management, and Engaging with Interaction. The study analyzed twenty-five paired interactions from the Cambridge English Language Assessment. The results, derived from mixed-effect modeling and stepwise regression analyses, highlight that rate and pitch measures are significant predictors of overall speaking scores. Furthermore, in-depth analysis identified specific suprasegmental features that contributed to the scores of each criterion: Sensitivity to Situation (rate), Language Use (pitch), Content Delivery (pitch), and Engaging with Interaction (rate). The findings of this study hold significant implications for language learning, speaking assessment, and pedagogy.