Effects of a Closed-Loop "Subspecialty-Mapping-Questioning" Model Based on Cognitive Load Theory on the Clinical Decision-Making Ability of ICU Nurses: A Mixed-Methods Study

Abstract Background: In intensive care unit (ICU), traditional training models fail to meet the integrated cognitive demands. Additionally, subspecialty training and mind mapping have rarely been applied with a unifying theoretical framework for knowledge retention. Aims : Based on the Cognitive Load Theory and experiential learning cycle, this study aimed to construct and validate a closed-loop training model (Subspecialty-Mind Mapping-Rolling Quiz) to enhance ICU nurses' clinical decision-making, knowledge retention, self-efficacy and critical thinking. Design : An explanatory sequential mixed-methods design. Methods : The quantitative phase consisted of a cluster randomized controlled trial involving 196 nurses from 4 ICU units randomly assigned to either an intervention group (2 units, n=102) receiving the closed-loop training or a control group (2 units, n=94) receiving traditional training from January to June 2025. Participants' Lasater Clinical Judgment Rubric (LCJR), theoretical and practical examination, General Self-Efficacy Scale (GSES), Critical Thinking Disposition Inventory-Chinese Version (CTDI-CV) scores, and knowledge retention rates were compared at 6-month follow-up. In the qualitative phase, 16 participants were sampled for semi-structured interviews. Results : Quantitative results showed that the intervention group had significantly higher LCJR scores (t=12.917, p<0.01), post-intervention and delayed post-test theoretical and practical, GSES, and CTDI-CV scores (all p<0.05). Qualitative analysis identified four themes: reconstruction of cognitive schema, shift in learning identity, sustained activation of metacognition and incentives coexisting with challenges in implementation. Conclusion : The Subspecialty-Mind Mapping-Rolling Quiz enhanced ICU nurses' clinical decision-making, knowledge retention, self-efficacy, and critical thinking ability. By fostering knowledge internalization and contextualized retrieval, this model serves as an effective training solution.