Research Methods for IDs and TBLT: A Substantive and Methodological Review

Abstract As part of ongoing efforts to characterize the extent to which tasks and interaction-driven language learning are influenced by individual differences (IDs), task-based researchers have thus far examined variables like learners’ levels of L2 anxiety, motivation, cognitive creativity, working memory capacity, and aptitude. Building on a tradition of prior syntheses in task-based language teaching (TBLT, e.g., Plonsky & Kim, 2016), we carried out a methodological review of the practices used by researchers who have examined learners’ IDs in task-based language learning. We searched journal articles published between 2000 and 2023 and identified 135 unique samples for analysis. Each empirical study was coded for relevant contextual and demographic variables as well as for methodological features related to the investigation of individual differences. We observed that of 30 individual differences investigated in TBLT research over the last two decades, the top five most common were motivation, working memory, L2 proficiency, anxiety, and aptitude. Interesting patterns related to operationalizations, instruments, coding, analyses, and reporting practices. In this paper, we report these results and summarize the most and least common methodological practices, also pointing out gaps and possibilities for future directions. We conclude with recommendations for researchers interested in embarking on empirical investigations of individual differences and TBLT based on best practices.