Integrated PBL-CBL-CTTM Teaching to Enhance Clinical Self-Efficacy in Endocrine Critical Illness Among Internal Medicine Residents: An RCT

Online-Offline Integrated Multimodal Teaching Combining PBL, CBL, and CTTM to Enhance Clinical Self-Efficacy in Endocrine and Metabolic Critical Illness Among Internal Medicine Residents: A Convergent Parallel Mixed-Methods Randomized Controlled Trial

This randomized controlled trial evaluates whether an integrated online-offline multimodal teaching approach combining Problem-Based Learning (PBL), Case-Based Learning (CBL), and Case Three-Dimensional Teaching Method (CTTM) improves clinical self-efficacy and hands-on proficiency in managing endocrine and metabolic critical illness among internal medicine residents, compared to traditional lecture-based learning (LBL).

Ninety internal medicine residents on their first endocrine rotation will be randomly assigned in a 1:1:1 ratio to three groups: (1) Control group receiving traditional LBL alone; (2) Experimental group 1 receiving PBL plus LBL; (3) Experimental group 2 receiving the integrated PBL-CBL-CTTM closed-loop teaching program. All groups receive a standardized 12-hour curriculum on endocrine and metabolic critical illness, including diabetic ketoacidosis, hyperosmolar hyperglycemic syndrome, thyroid storm, and refractory hypoglycemia.

The primary outcome is the clinical skills assessment score (0-50 points). Secondary outcomes include theoretical examination scores, General Self-Efficacy Scale (GSES) scores, a self-developed Endocrine High-Risk Management Self-Efficacy Source Questionnaire (four dimensions based on Bandura's self-efficacy theory), teaching satisfaction, and semi-structured focus group interviews.

The study was conducted from September 2025 to August 2026 at the Fourth Affiliated Hospital of Anhui Medical University, Chaohu, China. This study aims to establish an evidence-based, replicable teaching model that addresses the gap between theoretical knowledge and clinical confidence in managing endocrine emergencies among residents.

Inclusion Criteria:

• Full-time internal medicine residents undergoing their first endocrine rotation at the Fourth Affiliated Hospital of Anhui Medical University
• No prior endocrine remedial training or advanced study experience
• No independent management experience with endocrine and metabolic critical cases
• Ability to complete all 12 hours of standardized curriculum and all post-intervention assessments
• Voluntary participation with written informed consent

Exclusion Criteria:

• Prior completion of an endocrine rotation or specialized endocrine training
• Prior independent management experience in diabetic ketoacidosis, hyperosmolar hyperglycemic syndrome, thyroid storm, or refractory hypoglycemia
• Inability to complete the full 12-hour teaching schedule due to clinical duties, leave, or rotation transfer
• Concurrent participation in other teaching intervention research projects
• Decline to provide written informed consent or withdrawal before randomization