The time between tasks in task repetition research: a systematic review

This article reports on a systematic review of oral task repetition research carried out between 1996 and 2023. This review focuses on the methodological features of these studies, specifically on issues related to how tasks have been spaced and repeated within this body of research. This review starts with an overview of the concept of input spacing and the major methodological paradigms that have been used to investigate it across the psychological sciences. It then discusses task repetition, providing definitions and elaborations of theoretical models, discussing why spacing might influence task performance, and how this informs the synthesized research. The article then presents a synthesis of the methods and results of the 107 studies that have been analysed as part of the synthesis. The methodological synthesis includes analyses of how spacing has been implemented, the number of times tasks were repeated, and how researchers have justified their methodological decisions. The results of the synthesis highlight the need for greater systematicity and theoretical rationales for choice of spacing intervals, number of task repetitions, and transparency in reporting practices. The methods and results are discussed by identifying trends, exemplifying practices, and recommending solutions.