Spaced Retrieval Effects on Learning Capacity in Patients With Mild-to-Moderate Cognitive Impairment

Abstract: Spaced retrieval (SR) improves the learning capacity of patients with memory deficits, while evidence on its long-term and generalization to other untrained measures is quite inconsistent. This systematic review was to analyze evidence on the SR effectiveness on recall performance, follow-up, and generalization measures in patients with cognitive impairment. A systematic search on PUBMED, MEDLINE, Web of Science, PubPsych, and ProQuest was performed between November 2020 and January 2021. The benefit effect of SR on direct, generalization, and long-term measures did not significantly differ from other learning techniques and the effect sizes even increased when SR was combined with another method. Effects on generalization depended on the similarity between the trained and untrained material. Existing evidence on SR remains quite scarce, mainly based on studies with moderate methodological quality giving rise to very heterogeneous results. Further investigation is still needed to overcome previous methodological limits and extend evidence to the immediate and long-term effects of the simultaneous application of different learning methods.