Randomized Controlled Trial of Multi-Patient CT-Derived Digital Twin Anatomical Variability Training to Shorten the Clinical Learning Curve for Bronchoscopy

Inclusion Criteria: Trainee Participants: 1. Residents, fellows, or specialty trainees in pulmonary medicine, critical care medicine, thoracic surgery, anesthesiology, or related specialties whose training programs require flexible bronchoscopy training. 2. Previously performed ≤5 flexible bronchoscopies as primary operator. 3. No prior formal bronchoscopy simulation training course experience. 4. Able and willing to provide written informed consent and permit use of training logs, procedural videos, Ontario Bronchoscopy Assessment Tool (OBAT) scores, and clinical learning curve data for research purposes. Patient Participants: 1. Age ≥18 years. 2. Scheduled to undergo elective low-risk or low-to-moderate-risk diagnostic flexible bronchoscopy. 3. Clinically suitable for supervised novice-performed airway inspection, bronchoalveolar lavage, simple brushing, or other low-risk sampling procedures considered safe by the supervising bronchoscopist. 4. Able to understand and provide written informed consent and willing to complete pre-procedure anxiety and post-procedure experience questionnaires. Exclusion Criteria: Trainee Participants: 1. Previously performed \>5 flexible bronchoscopies or previously completed a structured bronchoscopy simulation training program. 2. Planned departure from the training program during the study period or anticipated inability to complete follow-up through at least clinical cases 1-30. 3. Unable to participate in simulation training or unwilling to permit procedural video recording. 4. Significant additional bronchoscopy training exposure outside the study protocol; such cases may not necessarily be excluded but will be documented and addressed in sensitivity analyses. Patient Participants: 1. Emergency bronchoscopy, intubated intensive care unit patients, severe hypoxemia, or significant hemodynamic instability. 2. Therapeutic bronchoscopy, complex central airway stenosis, high bleeding risk, procedures requiring advanced interventional techniques, or cases considered unsuitable for novice participation. 3. Complex sampling procedures such as EBUS-TBNA, transbronchial lung biopsy, or cryobiopsy will not be included in the primary endpoint case set and may be analyzed separately as exploratory subgroups or in future studies. 4. Refusal of trainee participation or refusal of procedural recording and/or questionnaire completion.