Synthesizing Research on Language Learning and Teaching (review)

What is research synthesis? In this first collection of work on research synthesis in applied linguistics, Norris and Ortega define it as a systematic secondary review of accumulated primary research studies. Under this definition, the evaluative characteristic is not considered as critical as in traditional meta-analysis. The primary purpose of research synthesis is to 'integrate available research, such that both patterns and inconsistencies may be identified with accuracy' (p. 6).

The book undertakes to elucidate diverse secondary research techniques with seven empirical synthesis studies in language learning and teaching. These studies demonstrate that synthesis can take a variety of forms. It can be a quantitative meta-analysis that seeks summative answers of main and moderating effects (e.g., chapter 2 by Dinsmore and chapter 6 by Taylor, Stevens, and Asher) and/or critical synthesis of research practices (e.g., chapter 3 by Keck and Iberri-Shea, chapter 4 by Russell and Spada, and chapter 5 by Jeon and Kaya). It can be a qualitative meta-synthesis that interpretively integrates and reconceptualizes ethnographic knowledge about a given topic (e.g., chapter 7 by Téllez and Waxman). It can even be in a form of historiography that investigates the shift in research findings and/or practices across time (e.g., chapter 8 by Thomas). Although the meta-synthesis approach is at its early stage of development, and historiography is still being introduced into research synthesis, this book brings to light the need for diversity in synthesizing primary studies and demonstrates the methodological potential of research synthesis in applied linguistics.

The book distinguishes itself with its emphasis on applications to language learning and teaching. Without assuming that readers have prior knowledge of the synthesis approach, Norris and Ortega target a wide range of readers, including graduate students, teachers, researchers, curriculum developers, and policy makers in applied linguistics. Elaborating on the key components of synthesis practices outlined in chapter 1, a major part of the book illustrates specific procedures of how to conduct research synthesis. Chapters 2 to 8 provide successful models from important domains of applied linguistics such as universal grammar, task-based interaction, corrective feedback, instructed pragmatic development, reading strategy training, effective teaching, and proficiency assessment. These models exemplify a variety of applications of specific forms of research synthesis. The models will not only appeal to those who are interested in the methodology of research synthesis but also to those who are interested in the different aspects of language discussed in this book.

Besides focusing on the values of research synthesis, the authors also point out its pitfalls. Some potential problems, especially those related to meta-analysis, are posed at the beginning of the book, such as publication bias in sampling primary studies, unreliable coding of studies, and inaccurate interpretation of effect sizes. Authors of the two final chapters approach these problems by reflecting on each of the models discussed, offering unique perspectives on the limitation in the conceptualization, methodology, and reporting of established research syntheses in applied linguistics. Ellis's argument in chapter 9 roots the bounds on human cognition in rationality, probability, and psychology. In chapter 10, Chaudron traces the historical development of research synthesis in second language research. Together, the authors in these three chapters identify the difficulties in furthering the applications of methods of synthesis to practical language research. More importantly they suggest a need for change in the actual interaction with language studies. To fulfil the potential of research synthesis in applied linguistics, Norris and Ortega point out, researchers need to acquire certain research ethics by 'thinking and acting synthetically.' This book provides an optimal basis for, and example of, such ethics. It systematically guides us to pursue theoretical and empirical grounds of both primary and secondary studies, to frame synthesis methods with key methodological features and epistemological affiliations, and to facilitate communication and dialogue among constituencies in a research community.

Most of the book is devoted to the investigation of quantitative meta-analysis. I thought it would have been more...