The Impact of Endoscopists' Experience and Learning Curves and Interendoscopist Variation on Colonoscopy Completion Rates

Background and Study Aims: Since its introduction in the late 1960s, the technology of colonoscopy has developed rapidly and the competence of endoscopists has increased. Nevertheless, it is not always possible to perform a complete colonoscopy. The aim of this study was to assess, in a population-based setting, the endoscopist-related factors influencing the completion rate, taking into account patient characteristics and changes in the technology over time.

Patients and Methods: All colonoscopy records between 1979 and 1995 in one Swedish county (population 258 000) were retrieved. Information was obtained about patient demographics, date of examination, endoscopist, indications, presence of diverticulosis, type of colonoscopy, findings, level of completion, complications, and reasons for incomplete colonoscopy. Completion rates were examined by univariate and multivariate analyses.

Results: Of 5494 colonoscopies, 4153 (75 %) were complete, and 78 % were diagnostic and 22 % therapeutic. In 70 %, findings were pathological, and 30 % were normal. The overall 30-day endoscopist-related complication rate was 0.3 %. Over time, the proportion of colonoscopies performed by endoscopists with greater experience increased and so did the completion rates. Completion rates were influenced by endoscopist's experience and to some extent by the intensity (the number of colonoscopies performed by the endoscopist during the previous 90 days). There was a large interendoscopist variation, at each level of experience, in the ability to perform a complete colonoscopy, implying substantial differences between individual learning curves.

Conclusions: The completion rate has increased over time, the major reason being greater competence of endoscopists. The finding of large interendoscopist variation, at each level of experience, in the ability to perform a complete colonoscopy supports the monitoring of endoscopists to maintain and improve performance.

References

• 1 Wolff W I. Colonoscopy: history and development.  Am J Gastroenterol. 1989;  84 1017-1025
• 2 Cirocco W C, Rusin L C. Factors that predict incomplete colonoscopy.  Dis Colon Rectum. 1995;  38 964-968
• 3 Saunders B P, Fukumoto M, Halligan S, et al. Why is colonoscopy more difficult in women?.  Gastrointest Endosc. 1996;  43 124-126
• 4 Church J M. Complete colonoscopy: how often? And if not, why not?.  Am J Gastroenterol. 1994;  89 556-560
• 5 Marshall J B, Barthel J S. The frequency of total colonoscopy and terminal ileal intubation in the 1990s.  Gastrointest Endosc. 1993;  39 518-520
• 6 Chak A, Cooper G S, Blades E W, et al. Prospective assessment of colonoscopic intubation skills in trainees.  Gastrointest Endosc. 1996;  44 54-57
• 7 Cass O W, Freeman M L, Peine C J, et al. Objective evaluation of endoscopy skills during training.  Ann Intern Med. 1993;  118 40-44
• 8 Parry B R, Williams S M. Competence and the colonoscopist: a learning curve.  Aust N Z J Surg. 1991;  61 419-422
• 9 Cass O W, Freeman M L, Cohen J, et al. Acquisition of competency in endoscopic skills (ACES) during training: a multicenter study (abstract).  Gastrointest Endosc. 1996;  43 308
• 10 Waye J D, Bashkoff E. Total colonoscopy: is it always possible?.  Gastrointest Endosc. 1991;  37 152-154
• 11 Hull T, Church J M. Colonoscopy - how difficult, how painful?.  Surg Endosc. 1994;  8 784-787
• 12 Nivatvongs S, Fryd D S, Fang D. How difficult is total colonoscopy (abstract)?.  Gastrointest Endosc. 1982;  28 140
• 13 Schmitt C M, Schultz S M, Lee J G, et al. The association between gender and difficult colonoscopy (abstract).  Gastrointest Endosc. 1994;  40 46
• 14 Waye J D. Colonoscopy intubation techniques without fluoroscopy. In: Hunt RH, Waye JD (eds). Colonoscopy: techniques, clinical practice and color atlas.  London; Chapman and Hall, 1981: 147-178
• 15 Cotton P B, Williams C B. Colonoscopy. In: Cotton PB, Williams CB (eds). Practical gastrointestinal endoscopy.  Oxford; Blackwell Scientific Publications, 1990 3rd ed.: 160-223
• 16 Webb W A. Colonoscoping the “difficult” colon.  Am Surg. 1991;  57 178-182
• 17 Galandiuk S. Colonoscopy to the cecum.  Semin Colon Rectal Surg. 1992;  3 18-23
• 18 Williams C B. Colonoscopy and polypectomy. In: Fielding LP, Goldberg SM (eds). Rob and Smith’s operative surgery - surgery of the colon, rectum and anus.  Oxford; Butterworth-Heinemann, 1993 5th ed.: 130-141
• 19 ASGE .Methods of granting hospital privileges to perform gastrointestinal endoscopy.  Manchester, MA; American Society for Gastrointestinal Endoscopy (ASGE) publication 1012. August 1992
• 20 Saifuddin T, Trivedi M, King P D, et al. Usefulness of a pediatric colonoscope for colonoscopy in adults.  Gastrointest Endosc. 2000;  51 314-317
• 21 Boyd N F, Pater J L, Ginsburg A D. Observer variation in the classification of information from medical records.  J Chron Dis. 1979;  32 327-332
• 22 Landis J R, Koch G G. The measurement of observer agreement for categorical data.  Biometrics. 1977;  33 159-174
• 23 SAS Institute Inc .SAS/STAT software: changes and enhancements through release 6.12.  Cary, NC; SAS Institute Inc., 1997: 247-348
• 24 Marshall J B. Technical proficiency of trainees performing colonoscopy: a learning curve.  Gastrointest Endosc. 1995;  42 287-291
• 25 Dafnis G, Blomqvist P, Påhlman L, et al. The introduction and development of colonoscopy within a defined population in Sweden.  Scand J Gastroenterol. 2000;  35 765-771
• 26 Zubarik R, Fleischer D E, Mastropietro C, et al. Prospective analysis of complications 30 days after outpatient colonoscopy.  Gastrointest Endosc. 1999;  50 322-328
• 27 Dafnis G, Granath F, Påhlman L, et al. Patient factors influencing the completion rate in colonoscopy. . Submitted for publication 2000
• 28 Anderson M L, Heigh R I, McCoy G A, et al. Accuracy of assessment of the extent of examination by experienced colonoscopists.  Gastrointest Endosc. 1992;  38 560-563
• 29 Leicester R J. Primary colonoscopy.  Baillière’s Clin Gastroenterol. 1991;  5 209-223
• 30 Heldwein W, Birkner B, Strauch L, et al. Quality assurance in colonoscopy in private practice and the hospital. The Gastroenterology Quality Circle (GEQC) Munich.  Dtsch Med Wochenschr. 1996;  121 1040-1045
• 31 Vennes J A, Ament M, Boyce H W Jr, et al. Principles of training in gastrointestinal endoscopy. American Society for Gastrointestinal Endoscopy. Standards of Training Committees. 1989 - 1990.  Gastrointest Endosc. 1992;  38 743-747
• 32 Macmillan A I, Cuschieri A. Assessment of innate ability and skills for endoscopic manipulations by the Advanced Dundee Endoscopic Psychomotor Tester: predictive and concurrent validity.  Am J Surg. 1999;  177 274-277
• 33 Hanna G B, Drew T, Cuschieri A. Technology for psychomotor skills testing in endoscopic surgery.  Semin Laparosc Surg. 1997;  4 120-124
• 34 Barrett D S, Green R G, Copeland S A. Arthroscopic and endoscopic skills: a method of assessment.  Ann R Coll Surg Engl. 1991;  73 100-104