Applied linguistics research in three decades: a methodological synthesis of graduate theses in an EFL context

The recent years have witnessed an increasing awareness in methodological issues in the field of applied linguistics, which brought about what Byrnes (Mod Lang J 97:825–827, 2013) and Plonsky (The Routledge handbook of instructed second language research, Routledge, New York, pp 505–521, 2017) referred to as “methodological turn” and “methodological awareness”, respectively. To contribute to this fresh line of research, this review, drawing on the methodological synthetic techniques, sought to describe and evaluate the aggregative and developmental status of experimental research in an EFL context. Having developed an experimental coding sheet and a manual book, we selected the eligible studies based on informed included/excluded criteria. As a result, we analyzed 285 unpublished applied linguistics MA theses which were distributed over a 30-year period. The cumulative results revealed a set of strengths and deficiencies across the data set. Of notable findings were inconsistent reporting practices (e.g., low statistical power, the minimum use of confidence intervals and effect sizes, and inconsistent reporting of p values). However, signs of improvement over three decades were conspicuous (e.g., reporting effect sizes, checking statistical assumptions, etc.). Implications and recommendations for the research methodologists, postgraduate students, and policy makers are discussed.