Join us for a conversation with Professor Daniel Olson from Purdue University as he discusses the following:

Control groups are widely recognized as an essential component of experimental research, yet surprisingly little attention has been paid to how control groups are designed in second language acquisition (SLA). This talk presents findings from a large-scale systematic review of control group practices in experimental research on second language pronunciation. The review examines the different control group types found in SLA research, their relative frequency, and key characteristics of randomization and matching for exposure. The results highlight nine distinct control group types, each providing fundamentally different information about instructional effectiveness, maturation, exposure, and alternative explanations for observed change. The findings reveal substantial variation in how researchers conceptualize, describe, and implement control conditions, with important implications for the interpretation of intervention effects and the comparability of findings across studies. We will discuss preliminary recommendations for designing, reporting, and interpreting control groups, as well as broader implications for refining methodological practices in SLA research.