Simulation in Surgical Endoscopy

  • Sarah B. Placek
  • Brenton R. Franklin
  • E. Matthew RitterEmail author
Part of the Comprehensive Healthcare Simulation book series (CHS)


Simulation-based training has become a critical component for surgical endoscopy training. The different classes of platforms available include mechanical or physical, virtual reality, composite, and live animal models. Deciding which platform is appropriate is heavily dependent on the desired learning objectives and individual tasks or skills being practiced. This chapter will outline the various platforms available for basic and advanced endoscopy simulation, including their validity evidence as an assessment tool and demonstrated efficacy as a training modality. The simulation platforms will be compared with regard to their advantages and disadvantages when incorporating them into a training program, as well as their features, capabilities, targeted skills, and feedback potential. Additionally, endoscopy-specific curriculum development, feedback methodologies, and assessment will be discussed to promote best practices when employing surgical endoscopy into a trainee’s simulation experience. Simulation continues to advance, and the following can be used as a framework to aid in the development of an effective simulation training program for surgical endoscopy.


Surgical endoscopy Mastery learning Endoscopy simulators Simulation 


  1. 1.
    Reznick RK, MacRae H. Teaching surgical skills: changes in the wind. N Engl J Med. 2006;355:2664–9.CrossRefPubMedGoogle Scholar
  2. 2.
    Sweller J. Cognitive load during problem solving: effects on learning. Cogn Sci. 1988;12:257–85.CrossRefGoogle Scholar
  3. 3.
    van Merriënboer JJ, Sweller J. Cognitive load theory in health professional education: design principles and strategies. Med Educ. 2010;44:85–93.CrossRefPubMedGoogle Scholar
  4. 4.
    McCashland T, Brand R, Lyden E, de Garmo P. The time and financial impact of training fellows in endoscopy. CORI Research Project. Clinical Outcomes Research Initiative. Am J Gastroenterol. 2000;95:3129–32.CrossRefPubMedGoogle Scholar
  5. 5.
    Bini EJ, Firoozi B, Choung RJ, et al. Systematic evaluation of complications related to endoscopy in a training setting: a prospective 30-day outcomes study. Gastrointest Endosc. 2003;57:8–16.CrossRefPubMedGoogle Scholar
  6. 6.
    ACGME Program requirements for graduate medical education in general surgery. 2016. Accessed on 14 Aug 2016.
  7. 7.
    ABS establishes new requirement for endoscopic training and assessment. 2014. Accessed 06 Jun 2016.
  8. 8.
    Zuckerman R, Doty B, Bark K, Heneghan S. Rural versus non-rural differences in surgeon performed endoscopy: results of a national survey. Am Surg. 2007;73:903–5.PubMedGoogle Scholar
  9. 9.
    Heneghan SJ, Bordley J 4th, Dietz PA, et al. Comparison of urban and rural general surgeons: motivations for practice location, practice patterns, and education requirements. J Am Coll Surg. 2005;201:732–6.CrossRefPubMedGoogle Scholar
  10. 10.
    Cass OW, Freeman ML, Peine CJ, et al. Objective evaluation of endoscopy skills during training. Ann Intern Med. 1993;118:40–4.CrossRefPubMedGoogle Scholar
  11. 11.
    Vargo JJ. North of 100 and south of 500: where does the “sweet spot” of colonoscopic competence lie? Gastrointest Endosc. 2010;71:325–6.CrossRefPubMedGoogle Scholar
  12. 12.
    Spier BJ, Benson M, Pfau PR, et al. Colonoscopy training in gastroenterology fellowships: determining competence. Gastrointest Endosc. 2010;71:319–24.CrossRefPubMedGoogle Scholar
  13. 13.
    Wexner SD, Garbus JE, Singh JJ. SAGES Colonoscopy Study Outcomes Group. A prospective analysis of 13,580 colonoscopies. Reevaluation of credentialing guidelines. Surg Endosc. 2001;15:251–61.CrossRefPubMedGoogle Scholar
  14. 14.
    Hazey JW, Marks JM, Mellinger JD, et al. Why fundamentals of endoscopic surgery (FES)? Surg Endosc. 2014;28:701–3.CrossRefPubMedGoogle Scholar
  15. 15.
    Poulose BK, Vassiliou MC, Dunkin BJ, et al. Fundamentals of endoscopic surgery cognitive examination: development and validity evidence. Surg Endosc. 2014;28:631–8.CrossRefPubMedGoogle Scholar
  16. 16.
    Vassiliou MC, Dunkin BJ, Fried GM, et al. Fundamentals of endoscopic surgery: creation and validation of the hands-on test. Surg Endosc. 2014;28:704–11.CrossRefPubMedGoogle Scholar
  17. 17.
    Singh S, Sedlack RE, Cook DA. Effects of simulation-based training in gastrointestinal endoscopy: a systematic review and meta-analysis. Clin Gastroenterol Hepatol. 2014;12:1611–23.CrossRefPubMedGoogle Scholar
  18. 18.
    Markman HD. A new system for teaching proctosigmoidoscopic morphology. Am J Gastroenterol. 1969;52:65–9.PubMedGoogle Scholar
  19. 19.
    Classen M, Ruppin H. Practical training using a new gastrointestinal phantom. Endoscopy. 1974;6:127–31.CrossRefGoogle Scholar
  20. 20.
    Buscaglia JM, Fakhoury J, Loyal J, et al. Simulated colonoscopy training using a low-cost physical model improves responsiveness of surgery interns. Color Dis. 2015;17:530–5.CrossRefGoogle Scholar
  21. 21.
    Sedlack RE. Simulators in training: defining the optimal role for various simulation models in the training environment. Gastrointest Endosc Clin N Am. 2006;16:553–63.CrossRefPubMedGoogle Scholar
  22. 22.
    Sturm LP, Windsor JA, Cosman PH, et al. A systematic review of skills transfer after surgical simulation training. Ann Surg. 2008;248:166–79.CrossRefPubMedGoogle Scholar
  23. 23.
    Tsuda S, Scott D, Doyle J, Jones DB. Surgical skills training and simulation. Curr Probl Surg. 2009;46:271–370.CrossRefPubMedGoogle Scholar
  24. 24.
    Colonoscopy (Lower GI Endoscopy) simulator type II. Accessed on 14 Aug 2016.
  25. 25.
    Colonoscope training model. Accessed on 14 Aug 2016.
  26. 26.
    EGD (EsophagoGastroDuodenoscopy) simulator. Accessed on 14 Aug 2016.
  27. 27.
    Plooy AM, Hill A, Horswill MS, et al. Construct validation of a physical model colonoscopy simulator. Gastrointest Endosc. 2012;76:144–50.CrossRefPubMedGoogle Scholar
  28. 28.
    Cox TC, Pearl JP, Ritter EM. SCOPE simulated colonoscopy objective performance evaluation. Surg Endosc. 2011;25(Suppl):s284.Google Scholar
  29. 29.
    Ritter EM, Cox TC, Trinca KD, Pearl JP. Simulated colonoscopy objective performance evaluation (SCOPE): a non-computer based tool for assessment of endoscopic skills. Surg Endosc. 2013;27:4073–80.CrossRefPubMedGoogle Scholar
  30. 30.
    Trinca KD, Cox TC, Pearl JP, Ritter EM. Validity evidence for the simulated colonoscopy objective performance evaluation scoring system. Am J Surg. 2014;207:218–25.CrossRefPubMedGoogle Scholar
  31. 31.
    Jirapinyo P, Kumar K, Thompson C. Validation of an endoscopic part-task training box as a skill assessment tool. Gastrointest Endosc. 2015;81:967–72.CrossRefPubMedGoogle Scholar
  32. 32.
    Thompson C, Jirapinyo P, Kumar N, et al. Development and initial validation of an endoscopic part-task training box. Endoscopy. 2014;46:735–44.CrossRefPubMedPubMedCentralGoogle Scholar
  33. 33.
    Wilcox V, Trus T, Salas N, et al. A proficiency-based skills training curriculum for the SAGES surgical training for endoscopic proficiency (STEP) program. J Surg Educ. 2014;71:282–9.CrossRefPubMedGoogle Scholar
  34. 34.
    Berger-Richarson D, Kurashima Y, von Renteln D, et al. Description and preliminary evaluation of a low-cost simulator for training and evaluation of flexible endoscopic skills. Surg Innov. 2016;23:183–8.CrossRefGoogle Scholar
  35. 35.
    Leung JW, Lee JG, Rojany M, et al. Development of a novel ERCP mechanical simulator. Gastrointest Endosc. 2007;65:1056–62.CrossRefPubMedGoogle Scholar
  36. 36.
    Frimberger E, von Delius S, Rösch T, et al. A novel and practicable ERCP training system with simulated fluoroscopy. Endoscopy. 2008;40:517–20.CrossRefPubMedGoogle Scholar
  37. 37.
    von Delius S, Thies P, Meining A, et al. Validation of the X-vision ERCP training system and technical challenges during early training of Sphincterotomy. Clin Gastroenterol Hepatol. 2009;7:389–96.CrossRefGoogle Scholar
  38. 38.
    Williams CB, Baillie J, Gillies DF, et al. Teaching gastrointestinal endoscopy by computer simulation: a prototype for colonoscopy and ERCP. Gastrointest Endosc. 1990;36:49–54.CrossRefPubMedGoogle Scholar
  39. 39.
    Noar MD. Robotics interactive endoscopy simulation of ERCP/sphincterotomy and EGD. Endoscopy. 1992;24(Suppl 2):539–41.CrossRefPubMedGoogle Scholar
  40. 40.
  41. 41.
    EndoVR interventional simulator. Accessed on 14 Aug 2016.
  42. 42.
    Bittner JG 4th, Marks JM, Dunkin BJ, et al. Resident training in flexible gastrointestinal endoscopy: a review of current issues and options. J Surg Educ. 2007;64:399–409.CrossRefPubMedGoogle Scholar
  43. 43.
    King N, Kunac A, Merchant A. A review of endoscopic simulation: current evidence on simulators and curricula. J Surg Educ. 2016;73(1):12–23.CrossRefPubMedGoogle Scholar
  44. 44.
    Triantafyllou K, Lazaridis L, Dimitriades G. Virtual reality simulators for gastrointestinal endoscopy training. World J Gastrointest Endosc. 2014;6:6–12.CrossRefPubMedPubMedCentralGoogle Scholar
  45. 45.
    Desilets DJ, Banerjee S, Barth BA, et al. Endoscopic simulators. Gastrointest Endosc. 2011;73:861–7.CrossRefPubMedGoogle Scholar
  46. 46.
    Mueller CL, Kaneva P, Fried GM, et al. Validity evidence for a new portable, lower-cost platform for the fundamentals of endoscopic surgery skills test. Surg Endosc. 2016;30:1107–12.CrossRefPubMedGoogle Scholar
  47. 47.
    Sedlack RE, Kolars JC. Colonoscopy curriculum development and performance-based assessment criteria on a computer-based endoscopy simulator. Acad Med. 2002;77:750–1.CrossRefPubMedGoogle Scholar
  48. 48.
    Sedlack RE, Kolars JC. Validation of a computer-based colonoscopy simulator. Gastrointest Endosc. 2003;57:214–8.CrossRefPubMedGoogle Scholar
  49. 49.
    Grantcharov TP, Carstensen L, Schulze S. Objective assessment of gastrointestinal endoscopy skills using a virtual reality simulator. JSLS. 2005;9:130–3.PubMedPubMedCentralGoogle Scholar
  50. 50.
    Mahmood T, Darzi A. A study to validate the colonoscopy simulator. Surg Endosc. 2003;17:1583–9.CrossRefPubMedGoogle Scholar
  51. 51.
    Eversbusch A, Grantcharov TP. Learning curves and impact of psychomotor training on performance in simulated colonoscopy: a randomized trial using a virtual reality endoscopy trainer. Surg Endosc. 2004;18:1514–8.CrossRefPubMedGoogle Scholar
  52. 52.
    Felsher JJ, Olesevich M, Farres H, et al. Validation of a flexible endoscopy simulator. Am J Surg. 2005;189:497–500.CrossRefPubMedGoogle Scholar
  53. 53.
    Koch AD, Buzink SN, Heemskerk J, et al. Expert and construct validity of the Simbionix GI Mentor II endoscopy simulator for colonoscopy. Surg Endosc. 2008;22:158–62.CrossRefPubMedGoogle Scholar
  54. 54.
    Ansell J, Mason J, Warren N, et al. Systematic review of validity testing in colonoscopy simulation. Surg Endosc. 2012;26:3040–52.CrossRefPubMedGoogle Scholar
  55. 55.
    Di Guilio E, Fregonese D, Casetti T, et al. Training with a computer-based simulator achieves basic manual skills for upper endoscopy: a randomized controlled trial. Gastrointest Endosc. 2004;60:196–200.CrossRefGoogle Scholar
  56. 56.
    Ahlberg G, Hultcrantz R, Jaramillo E, et al. Virtual reality colonoscopy simulation: a compulsory practice for the future colonoscopist? Endoscopy. 2005;37:1198–204.CrossRefPubMedGoogle Scholar
  57. 57.
    Haycock A, Koch AD, Familiari P, et al. Training and transfer of colonoscopy skills: a multinational, randomized, blinded, controlled trial of simulator versus bedside training. Gastrointest Endosc. 2010;71:298–307.CrossRefPubMedGoogle Scholar
  58. 58.
    Cohen J, Cohen S, Vora KC, et al. Multicenter, randomized, controlled trial of virtual-reality simulator training in acquisition of competency in colonoscopy. Gastrointest Endosc. 2006;64:361–8.CrossRefPubMedGoogle Scholar
  59. 59.
    Ende A, Zopf Y, Konturek P, et al. Strategies for training in diagnostic upper endoscopy: a prospective, randomized trial. Gastrointest Endosc. 2012;75:254–60.CrossRefPubMedGoogle Scholar
  60. 60.
    Ferlitsch A, Glauninger P, Gupper A, et al. Evaluation of a virtual endoscopy simulator for training in gastrointestinal endoscopy. Endoscopy. 2002;34:698–702.CrossRefPubMedGoogle Scholar
  61. 61.
    Moorthy K, Munz Y, Jiwanji M, et al. Validity and reliability of a virtual reality upper gastrointestinal simulator and cross validation using structured assessment of individual performance with video playback. Surg Endosc. 2004;18:328–33.CrossRefPubMedGoogle Scholar
  62. 62.
    Sedlack RE. Validation of computer simulation training for esophagogastroduodenoscopy: pilot study. J Gastroenterol Hepatol. 2007;22:1214–9.CrossRefPubMedGoogle Scholar
  63. 63.
    Hassan I, Osei-Agymang T, Radu D, et al. Simulation of laparoscopic surgery—four years’ experience at the Department of Surgery of the University Hospital Marburg. Wien Klin Wochenschr. 2008;120:70–6.CrossRefPubMedGoogle Scholar
  64. 64.
    Maschuw K, Hassan I, Bartsch DK. Surgical training using simulator. Virtual reality Chirurg. 2010;81:19–24.PubMedGoogle Scholar
  65. 65.
    Hochberger J, Neumann M, Hohenberger W, et al. Neuer Endoskopie-Trainer für die therapeutische flexible Endoskopie. Z Gastroenterol. 1997;35:722–3.Google Scholar
  66. 66.
    Hochberger J, Neumann M, Maiss J, et al. Erlanger Ausbildungssimulator für die interventionelle Endoskopie(EASIE): Eine neue Perspektive für die qualitdtsorientierte praktische Ausbildung. Endoskopie heute. 1998;4:23–5.Google Scholar
  67. 67.
    Maiss J, Hildebrand V, Bayer J, et al. Mini-EASIE: Ein neues, auf die Belange der interventionellen endoskopie reduziertes trainingsmodell. Endoskopie heute. 1999;12:53.Google Scholar
  68. 68.
    Hochberger J, Matthes K, Maiss J, et al. Training with the compactEASIE biologic endoscopy simulator significantly improves hemostatic technical skill of gastroenterology fellows: a randomized controlled comparison with clinical endoscopy training alone. Gastrointest Endosc. 2005;61:204–15.CrossRefPubMedGoogle Scholar
  69. 69.
    Maiss J, Millermann L, Heinemann K, et al. The compactEasie® is a feasible training model for endoscopic novices: a prospective randomized trial. Dig Liver Dis. 2007;39:70–8.CrossRefPubMedGoogle Scholar
  70. 70.
    Sedlack R, Baron T, Downing S, Schwartz A. Validation of a colonoscopy simulation model for skills assessment. Am J Gastroenterol. 2007;102:64–74.CrossRefPubMedGoogle Scholar
  71. 71.
    Ansell J, Arnaoutakis K, Goddard S, et al. The WIMAT colonoscopy suitcase model: a novel porcine polypectomy trainer. Color Dis. 2013;15:217–23.CrossRefGoogle Scholar
  72. 72.
    Ansell J, Hurley J, Horwood J, et al. The Welsh Institute for Minimal Access Therapy colonoscopy suitcase has construct and concurrent validity for colonoscopic polypectomy skills training: a prospective, cross-sectional study. Gastrointest Endosc. 2014;79:490–7.CrossRefPubMedGoogle Scholar
  73. 73.
    Sedlack R, Petersen B, Binmoeller K, Kolars J. A direct comparison of ERCP teaching models. Gastrointest Endosc. 2003;57:886–90.CrossRefPubMedGoogle Scholar
  74. 74.
    ASGE endoscopy simulator review. Gastrointest Endosc. 2011;73:861–7.Google Scholar
  75. 75.
    Cohen J, Nuckolls L, Mourant RR. Endoscopy simulators: lessons from the aviation and automobile industries. Gastrointest Endosc Clin N Am. 2006;16:407–23.CrossRefPubMedGoogle Scholar
  76. 76.
    Gomez PP, Willis RE, Sickle K. Evaluation of two flexible colonoscopy simulators and transfer of skills into clinical practice. J Surg Educ. 2015;72:220–7.CrossRefPubMedGoogle Scholar
  77. 77.
    Hill A, Horswill MS, Plooy AM, et al. Assessing the realism of colonoscopy simulation: the development of an instrument and systematic comparison of 4 simulators. Gastrointest Endosc. 2012;75:631–40.CrossRefPubMedGoogle Scholar
  78. 78.
    Bittner JG, Mellinger JD, Imam T, et al. Face and construct validity of a computer-based virtual reality simulator for ERCP. Gastrointest Endosc. 2010;71:357–64.CrossRefPubMedGoogle Scholar
  79. 79.
    Sorbi D, Vazquez-Sequeiros E, Wiersema MJ. A simple phantom for learning EUS-guided FNA. Gastrointest Endosc. 2003;57:580–3.CrossRefPubMedGoogle Scholar
  80. 80.
    Kim GH, Bang SJ, Hwang JH. Learning models for endoscopic ultrasonography in gastrointestinal endoscopy. World J Gastroenterol. 2015;21:5176–82.CrossRefPubMedPubMedCentralGoogle Scholar
  81. 81.
    Lujber L, Gerlinger I, Fábián G, et al. A novel and inexpensive model for practicing upper gastrointestinal endoscopy and percutaneous endoscopic gastrostomy techniques. Endoscopy. 2008;40(Suppl2):E73.CrossRefPubMedGoogle Scholar
  82. 82.
    Mittal MK, Kreitz KA, Resnick AS, et al. A novel approach for augmenting percutaneous endoscopic gastrostomy tube placement training. Simul Healthc. 2010;5:346–9.CrossRefPubMedGoogle Scholar
  83. 83.
    Yoshida N, Fernandopulle N, Inada Y, et al. Training methods and models for colonoscopic insertion, endoscopic mucosal resection, and endoscopic submucosal dissection. Dig Dis Sci. 2014;59:2081–90.CrossRefPubMedGoogle Scholar
  84. 84.
    Haycock AV, East JE, Swain D, Thomas-Gibson S. Development of a novel esophageal stricture simulation. Dig Dis Sci. 2010;55:321–7.CrossRefPubMedGoogle Scholar
  85. 85.
    Ritter EM, Scott DJ. Design of a proficiency-based skills training curriculum for the fundamentals of laparoscopic surgery. Surg Innov. 2007;14:107–12.CrossRefPubMedGoogle Scholar
  86. 86.
    Scott DJ, Ritter EM, Tesfay ST, et al. Certification pass rate of 100% for fundamentals of laparoscopic surgery skills after proficiency-based training. Surg Endosc. 2008;22:1887–93.CrossRefPubMedGoogle Scholar
  87. 87.
    Rosenthal ME, Ritter EM, Goova MT, et al. Proficiency-based fundamentals of laparoscopic surgery skills training results in durable performance improvement and a uniform certification pass rate. Surg Endosc. 2010;24:2453–7.Google Scholar
  88. 88.
    McGaghie WC, Siddall VJ, Mazmanian PE, et al. Lessons for continuing medical education from simulation research in undergraduate and graduate medical education. Chest. 2009;135(Suppl):62S–8S.CrossRefPubMedGoogle Scholar
  89. 89.
    McGaghie WC, Issenberg SB, Barsuk JH, Wayne DB. A critical review of simulation-based mastery learning with translational outcomes. Med Educ. 2014;48:375–85.CrossRefPubMedGoogle Scholar
  90. 90.
    Ericsson KA. Deliberate practice and the acquisition and maintenance of expert performance in medicine and related domains. Acad Med. 2004;79(Suppl):S70–81.CrossRefPubMedGoogle Scholar
  91. 91.
    Cook DA, Brydges R, Zendejas B, et al. Mastery learning for health professionals using technology-enhanced simulation: a systematic review and meta-analysis. Acad Med. 2013;88:1178–86.CrossRefPubMedGoogle Scholar
  92. 92.
    Barsuk JH, Cohen ER, Caprio T, et al. Simulation-based education with mastery learning improves residents’ lumbar puncture skills. Neurology. 2012;79:132–7.CrossRefPubMedPubMedCentralGoogle Scholar
  93. 93.
    Zendejas B, Cook DA, Bingener J, et al. Simulation-based mastery learning improves patient outcomes in laparoscopic inguinal hernia repair. Ann Surg. 2011;254:502–9.CrossRefPubMedGoogle Scholar
  94. 94.
    Barsuk JH, Cohen ER, Potts S, et al. Dissemination of a simulation-based mastery learning intervention reduces central line-associated bloodstream infections. BMJ Qual Saf. 2014;23:749–56.CrossRefPubMedGoogle Scholar
  95. 95.
    Barsuk JH, Cohen ER, McGaghie WC, Wayne DB. Long-term retention of central venous catheter insertion skills after simulation-based mastery learning. Acad Med. 2010;85(Suppl):S9–12.CrossRefPubMedGoogle Scholar
  96. 96.
    Issenberg SB, McGaghie WC, Petrusa ER, et al. Features and uses of high-fidelity medical simulations that lead to effective learning: a BEME systematic review. Med Teach. 2005;27:10–28.CrossRefPubMedGoogle Scholar
  97. 97.
    Walsh CM, Ling SC, Wang CS, Carnahan H. Concurrent versus terminal feedback: it may be better to wait. Acad Med. 2009;84(Suppl):S54–7.CrossRefPubMedGoogle Scholar
  98. 98.
    Kruglikova I, Grantcharov TP, Drewes AM, Funch-Jensen P. The impact of constructive feedback on training in gastrointestinal endoscopy using high-fidelity virtual-reality simulation: a randomised controlled trial. Gut. 2010;59:181–5.CrossRefPubMedGoogle Scholar
  99. 99.
    Lee JY, McDougall EM, Lineberry M, Tekian A. Optimizing the timing of expert feedback during simulation-based spaced practice of endourologic skills. Simul Healthc. 2016;11:257–63.CrossRefPubMedGoogle Scholar
  100. 100.
    Gardner A, Scott D, Willis R, et al. Is current surgery resident and GI fellow training adequate to pass FES? Surg Endosc. 2016;[Epub ahead of print].Google Scholar
  101. 101.
    Vassiliou MC, Kaneva PA, Poulose BK, et al. Global assessment of gastrointestinal endoscopic skills (GAGES): a valid measurement tool for technical skills in flexible endoscopy. Surg Endosc. 2010;24:1834–41.CrossRefPubMedGoogle Scholar
  102. 102.
    Sedlack RE. The Mayo colonoscopy skills assessment tool: validation of a unique instrument to assess colonoscopy skills in trainees. Gastrointest Endosc. 2010;72:1125–33.CrossRefPubMedGoogle Scholar
  103. 103.
    Koch AD, Haringsma J, Schoon EJ, et al. Competence measurement during colonoscopy training: the use of self-assessment of performance measures. Am J Gastroenterol. 2012;107:971–5.CrossRefPubMedGoogle Scholar

Copyright information

© Springer Nature Switzerland AG 2019

Authors and Affiliations

  • Sarah B. Placek
    • 1
  • Brenton R. Franklin
    • 1
  • E. Matthew Ritter
    • 1
    Email author
  1. 1.Department of Surgery, Division of General SurgeryUniformed Services University of the Health Sciences and Walter Reed National Military Medical Center, National Capital Region Simulation ConsortiumBethesdaUSA

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