title: A study to validate the colonoscopy simulator.
abstract: BACKGROUND
  The aim of this study was to investigate the relation between clinical experience and performance with regard to colonoscopic procedures performed on the HT Immersion Medical Colonoscopy Simulator. The hypothesis is that the performance of novice, intermediate, and experienced operators is different on simulators, just as it is on real patients.
  
  
  METHODS
  25 Postgraduate doctors were recruited and divided into three groups according to their level of colonoscopic experience. Candidates were asked at random to perform colonoscopy on module 3 or 4 of the HT Immersion Medical Colonoscopy Simulator. Modules 3 and 4 have built-in complex loops, and can demonstrate the candidate's ability either to avoid or undo the loop. Candidates in the first group, termed "novice," each had performed fewer than 10 colonoscopies and included four preregistration house officers (PRHOs), five specialist trainee resistrars (SpRs) and two consultants. This novice group had completed 80 episodes among them. In the second group, termed "intermediate," each candidate had performed between 11 and 100 colonoscopies, and the candidates included five SpRs and two research fellows. This intermediate group had completed 65 episodes. Members of the third group, termed "experienced" each had performed more than 101 colonoscopies, and included one SpR and six consultants. This experienced group had completed 45 episodes between them. A time result of 3,600 s (1 h) was used to denote perforation.
  
  
  RESULTS
  The experienced group were shown to perform better than the intermediate group, which in turn performed better than the novice group. The assessment was based on multiple factors including time taken to complete the test, percentage of the colonic mucosa visualized, incidence of colonic perforations, and path length used. The results were highly significant statistically for all these factors ( p < 0.000) except in path length used.
  
  
  CONCLUSIONS
  This study demonstrated that operators who differ in terms of their clinical experience and technical ability also differ in their performance of simulated colonoscopy. Thus, the findings have shown the simulator technology to be a powerful discriminator of manipulative skills in colonoscopy. The clinical differences that exist between novices and experts in terms of experience and technical expertise in endoscopic procedures are reflected by statistically significant differences in performance on the simulator. It is therefore reasonable to argue that improving proficiency on the simulator may translate into improvements in clinical practice. This study has validated the use of the HT Medical Immersion Colonoscopy Simulator to discriminate among subjects with different levels of experience.
authors.affiliation: Academic Surgical Unit, Imperial College and St Mary's Hospital, London, England.
authors.forename: T
authors.initials: T
authors.lastname: Mahmood
authors.forename: A
authors.initials: A
authors.lastname: Darzi
mesh_terms: D003113:Colonoscopy / Q000379:methods* / Q000706:statistics & numerical data; D003198:Computer Simulation; D003194:Computer-Assisted Instruction; D004502:Education, Medical, Continuing; D004724:Endoscopy / Q000193:education*; D005246:Feedback; D006801:Humans; D015994:Incidence; D007416:Intestinal Perforation / Q000453:epidemiology; D008131:London; D013647:Task Performance and Analysis; D014584:User-Computer Interface