Multisite research (MSR) offers the key advantages of greater statistical power and external validity via larger and more diverse participant pools. In second language acquisition (SLA) research, recent developments in meta-analysis have created a robust foundation for MSR. Although logistical and financial obstacles can complicate expansion…

The involvement load hypothesis (ILH) was designed to predict the effectiveness of instructional tasks for incidental L2 vocabulary learning. In this meta-analysis we examined 398 effect sizes from 42 empirical studies (N = 4,628) to explore (a) the overall predictive ability of the ILH, (b) the relative effects of different components of the ILH…

We propose a new framework for conceptualizing measures of instructed second language (L2) pronunciation performance according to three sets of parameters: (a) the constructs (focused on global vs. specific aspects of pronunciation), (b) the scoring method (human raters vs. acoustic analyses), and (c) the type of knowledge elicited (controlled vs.…

This study applied systematic meta-analytic procedures to summarize findings from experimental and quasi-experimental investigations into the effectiveness of using the tools and techniques of corpus linguistics for second language learning or use, here referred to as data-driven learning (DDL). Analysis of 64 separate studies representing 88…

This article reports a meta-analysis of studies that investigated the relative effectiveness of comprehension-based instruction (CBI) and production-based instruction (PBI). The meta-analysis only included studies that featured a direct comparison of CBI and PBI in order to ensure methodological and statistical robustness. A total of 35 research…

This study employed synthetic and meta-analytic techniques to review the literature on the Cognition Hypothesis, which predicts that increasing task complexity influences the quality of second language production. Based on 8 inclusion criteria, 17 published studies were synthesized according to key features. A subset of these studies (k = 9) was…

A meta-analysis was conducted to investigate the effects of explicit and implicit instruction on the acquisition of simple and complex grammatical features in English. The target features in the 41 studies contributing to the meta-analysis were categorized as simple or complex based on the number of criteria applied to arrive at the correct target…