Endoscopy 1999; 31(9): 702-706
DOI: 10.1055/s-1999-146
Original Article
Georg Thieme Verlag Stuttgart · New York

Acquisition of Competence in Colonoscopy: The Learning Curve of Trainees

P. S.Tassios, S. D.Ladas, I. Grammenos, K. Demertzis, S. A.Raptis
  • Gastroenterology Unit, Second Dept. of Internal Medicine, Evangelismos Hospital, Athens University, Athens, Greece
Further Information

Publication History

Publication Date:
31 December 1999 (online)

Background and Study Aims: Most official training programs in colonoscopy recommend that trainees should carry out a minimum of 100 procedures, but limited data exist on the technical progress of trainees. The aim of our study was to estimate the number of supervised procedures required for obtaining competence in colonoscopy.

Materials and Methods: Between 1990 and 1997 we have prospectively evaluated the performance of eight consecutive trainees in colonoscopy. The extent of intubated colon was recorded after each endoscopic procedure. Regression analysis was used to study the effect on the trainees' success rates on the number of colonoscopies which they had done.

Results: Out of 2255 colonoscopies carried out over an 8-year period 1408 were suitable for evaluation, fulfilling the training criteria for diagnostic colonoscopy. Se-nior staff (n = 2) did 430 colonoscopies with a success rate of 91 %, which was significantly reduced to 79 % (344/434 colonoscopies; χ2 = 20.67, df = 1, P < 0.001), when taking over colonoscopies which trainees had failed to complete. Regression analysis of trainees' data (y = 88.97 − (2185/x), r = 0.74, F1, 21 = 23.43, P < 0.001) showed success rates of 67 % (95 % Cl, 59 to 75 %) and 77 % (95 % Cl, 66 to 88 %), when 100 and 180 procedures, respectively, had been done. These figures had been attained by the end of the second and third year of training in colonoscopy.

Conclusions: Our regression analysis model shows the technical progress of trainees over a 3-year period as they learned how to carry out colonoscopy. Depending on individual skill, between 100 - 180 procedures, done over a 2 - 3-year period, are required before trainees can be considered competent in colonoscopy.


  • 1 Cass OW, Freeman ML, Peire CJ, et al. Objective evaluation of endoscopy skills during training.  Ann Int Med. 1993;  118 40-44
  • 2 Church JM. Learning colonoscopy: the need for patience (patients) [abstract].  Am J Gastroenterol. 1993;  88 1569
  • 3 Marshall JB. Technical proficiency of trainees performing colonoscopy: a learning curve.  Gastrointest Endosc. 1995;  42 287-291
  • 4 Chak A, Cooper GS, Blades EW, et al. Prospective assessment of colonoscopic intubation skills in trainees.  Gastrointest Endosc. 1996;  44 54-57
  • 5 European Union of Medical Specialists .European Board of Gastroenterology: An Introduction to the European Diploma of Gastroenterology. 1993
  • 6 Beattie AD, Greff M, Lamy V, Mallinson CN. The European Diploma of Gastroenterology: progress towards harmonization of standards.  Eur J Gastroenterol Hepatol. 1996;  8 403-406
  • 7 Working Party of the Endoscopy Section of the British Society of Gastroenterology .Recommendations of the British Society of Gastroenterology. A Report of a Working Party of the Endoscopy Section of the British Society of Gastroenterology on the Staffing of Endoscopy Units. British Society of Gastroenterology. 1987
  • 8 Friedman LS, Taylor IL. Development of a core curriculum for gastroenterology fellowship training. In: Friedman LS, Van Dam J, Proceedings of the Second GLC Training Directors' Workshop: the effects of changes in government policy on training in gastroenterology. Development of a core curriculum for gastroenterology fellowship training. Gastrointest Endosc 1995 41: 644-645
  • 9 American Society for Gastrointestinal Endoscopy's Standards of Training Committees . Principles of training in gastrointestinal endoscopy.  Gastrointest Endosc. 1992;  38 743-746
  • 10 The Gastroenterology Leadership Council . Training the gastroenterologist of the future: the gastroenterology core curriculum.  Gastroenterology. 1996;  110 1266-1300
  • 11 Friedman LS. How long does it take to learn endoscopy [editorial]?.  Gastrointest Endosc. 1995;  42 371-373
  • 12 Ladas SD, Giorgiotis C, Pipis P, et al. Sedation for upper gastrointestinal endoscopy: time for reappraisal [letter]?.  Gastrointest Endosc. 1990;  36 417-418
  • 13 DiMagno EP, Bond JH. Colonoscopy.  In: American Society for Gastrointestinal Endoscopy Guidelines for Training and Practice. Policy and procedure manual for gastrointestinal endoscopy. 1997: 9-12
  • 14 Baillie J, Ravich WJ. On endoscopic training and procedural competence [editorial].  Ann Intern Med. 1993;  118 73-74
  • 15 Cass OW, Freeman ML, Cohen J, et al. Acquisition of competencey in endoscopic skills (ACES) during training: a multicenter study [abstract].  Gastrointest Endosc. 1996;  43 308
  • 16 Cataldo PA. Colonoscopy without sedation.  Dis Colon Rectum. 1996;  39 257-261
  • 17 Eckardt VF, Kanzler G, Schmitt T, Eckardt AJ. Complications and adverse effects of colonoscopy with selective sedation [abstract].  Gastrointest Endosc. 1999;  49 560-565
  • 18 Silvis SE, Nebel O, Rogers G, Sugawa C, Mandelstam P. Endoscopic complications.  JAMA J Am Med Assoc. 1976;  9 928-931
  • 19 Williams CB. Endoscopy teaching: time to get serious [letter].  Gastrointest Endosc. 1998;  47 429-431
  • 20 Noar MD. The next generation of endoscopy simulation: minimally invasive surgical skills simulation.  Endoscopy. 1995;  27 81-85
  • 21 Rey JF, Romanczyk T. The development of experimental models in the teaching of endoscopy: an overview.  Endoscopy. 1995;  27 101-105
  • 22 Cass OW. Objective evaluation of competence: technical skills in gastrointestinal endoscopy.  Endoscopy. 1995;  27 86-89

S. D. LadasM.D. 

Gastroenterology Unit

2nd Dept. of Internal Medicine

Athens University, Evangelismos Hospital

POB141 27

115 10 Athens


Phone: + 30-1-7210213

Email: sdladas@hol.gr