2005 SAGES Abstracts

POSTER ABSTRACTS
urement tools. Rating scales used during live observation of
operative performance may be divided into global, procedurespecific
and checklist-based. These scales may also be used
for retrospective video-based observation with a resultant
increase in objectivity of the assessment, though it is unclear
which type of scale would be the most reliable for this purpose.
The aim of this study is to define the optimal scale for
video-based assessment of technical skill in laparoscopic surgery.
Methods: Twenty-eight laparoscopic cholecystectomies (LC)
performed by a total of 17 surgeons were recorded, following
the confirmation of informed consent from all patients and
surgeons involved in the cases. Each LC was assigned a code,
and rated by three other experienced laparoscopic surgeons in
a blinded manner on each of four rating scales. These were
the OSATS global rating scale of technical skill, a modified
OSATS global rating scale specifically adapted for video-based
assessment of laparoscopic surgery, a procedure-specific rating
scale, and finally a procedural checklist. Scores for each
procedure were collated, and analysed using Cronbach?s
alpha test for inter-rater reliability.
Results: The inter-rater reliabilities for each of the four rating
scales were as follows: OSATS (0.79); modified OSATS for
video-based observation (0.75); procedure-specific rating scale
(0.82); and procedural checklist (0.48).
Conclusions: OSATS, modified OSATS and the procedure-specific
scale all possess high inter-rater reliabilities, even though
the assessment is based upon retrospective, blinded, videobased
observation of performance. Such a method can ensure
increased objectivity and may be performed after the event,
making the assessment more feasible by not requiring the
presence of expert faculty to be available at the time of the
procedure. Finally, this study did not find the checklist to be a
reliable method of assessment, replicating the results of previous
work in this field.
P337–Minimally Invasive Other
THE OPTIMAL METHOD OF TRAINING ON A VIRTUAL REALI-
TY LAPAROSCOPIC SIMULATOR, R Aggarwal MD, G Dew,J
Hance MD,N Selvapatt,A Darzi MD, Department of Surgical
Oncology & Technology, Imperial College London, UK.
Introduction: Virtual reality (VR) laparoscopic simulators have
been shown to teach the skills required for laparoscopic surgery.
However, with increased fidelity and on-screen feedback,
the question should be asked whether it is necessary to have
an expert tutor available during every training session? It is
the aim of this study to determine the optimal method of feedback
to teach the skills required for laparoscopic suturing.
Methods: Forty laparoscopic novices trained on laparoscopic
VR simulators in a stepwise approach, commencing with a
previously validated basic skills curriculum on the MIST-VR
simulator. Subjects then completed five half-hour sessions on
the laparoscopic suturing module of the LapSim VR simulator.
Prior to their first LapSim session, subjects were randomly
allocated to one of four groups, each group receiving a different
type of feedback during their training sessions. The groups
received either expert tutor feedback, checklist feedback, VR
simulator feedback, or no feedback. Assessments of laparoscopic
suturing skill were carried out at the beginning and end
of each subject?s training period, using a synthetic bowel
model placed in a video trainer. Each subject?s performance
was scored objectively using a validated motion analysis system,
together with blinded checklist scoring of videos of each
procedure. Data analysis used non-parametric tests, p