Abstract
Digital flashcards are widely used in foreign language vocabulary learning. Research attributes their effectiveness to retrieval practice, where learners actively recall target information, thereby enhancing learning performance. The superiority of retrieval practice over non-retrieval methods such as restudying is referred to as the retrieval practice effect (RPE). Despite extensive research on the RPE, two key questions remain underexplored: how the number of learning rounds modulates the RPE in digital flashcard learning and whether the benefits of retrieval practice are consistently observed across different test modalities, a factor related to the context-dependence of memory. To address these questions, 108 Chinese-English bilinguals learned 60 Swahili-Chinese word pairs using two study methods (retrieval practice vs. restudying) under 3- or 4-round learning conditions, followed by cued-recall tests administered 30 min after learning, using both paper- and computer-based formats. Results showed that the RPE increased with more learning rounds. Additionally, retrieval practice consistently outperformed restudying method across different test modalities. These findings underscore the robustness of retrieval-based digital flashcard learning and provide practical insights for optimizing vocabulary instruction through strategic repetition scheduling.