Objectives: The aim of this article was to identify and prospectively investigate simulated ultrasound-guided targeted liver biopsy performance metrics as differentiators between levels of expertise in interventional radiology.Methods: Task analysis produced detailed procedural step documentation allowing identification of critical procedure steps and performance metrics for use in a virtual reality ultrasound-guided targeted liver biopsy procedure. Consultant (n=14; male=11, female=3) and trainee (n=26; male=19, female=7) scores on the performance metrics were compared. Ethical approval was granted by the Liverpool Research Ethics Committee (UK). Independent t-tests and analysis of variance (ANOVA) investigated differences between groups.Results: Independent t-tests revealed significant differences between trainees and consultants on three performance metrics: targeting, p=0.018, t=-2.487 (-2.040 to -0.207); probe usage time, p=0.040, t=2.132 (11.064 to 427.983); mean needle length in beam, p=0.029, t=-2.272 (-0.028 to -0.002). ANOVA reported significant differences across years of experience (0-1, 1-2, 3+ years) on seven performance metrics: no-go area touched, p=0.012; targeting, p=0.025; length of session, p=0.024; probe usage time, p=0.025; total needle distance moved, p=0.038; number of skin contacts, p<0.001; total time in no-go area, p=0.008. More experienced participants consistently received better performance scores on all 19 performance metrics.Conclusion: It is possible to measure and monitor performance using simulation, with performance metrics providing feedback on skill level and differentiating levels of expertise. However, a transfer of training study is required.

To validate a virtual reality simulator suitable for training Interventional Radiology (IR) skills. Task Analysis (TA) was employed to create a detailed description of a Liver Biopsy procedure, from which critical procedure steps (CPS) were identified. Engineers and computer scientists used the TA and CPS to build a simulator capable of measuring performance. Hierarchical and cognitive TA was carried out using interviews (n=12) with subject matter experts, and observation and recording of actual procedures (n=4). CPS were identified through interviews (n=12) and questionnaires (n=8). Engineers and computer scientists used the TA and CPS to build a training simulator capable of measuring performance. The discriminant validity of the simulator was investigated by measuring performance on a simulated Liver Biopsy procedure. The validation study was conducted at three UK clinical centres and participants were a convenience sample recruited on site with varying degrees of experience (consultants n=14, trainees n=26). The Liver Biopsy TA described174 procedural steps and 22 performance metrics were included in the simulator. Independent t-tests revealed significant differences between consultants (n=14) and trainees (n=26) on 4 performance metrics. ANOVA revealed significant differences between three groups with differing levels of experience in IR (< 1 year experience, 1-2 years, or 3+ years) on 7 performance metrics. Significant performance metrics were: no go area touched; targeting; length of session; probe usage time; total needle distance moved; number of skin contacts; total time in no go area. All 22 performance metrics followed the predicted pattern with level of performance consistently reflecting experience. The use of cognitive task analysis when developing training simulators allows the development of metrics that are a valid discriminator of skill between experts and novices. The indication is that simulation could be a useful training tool that can reflect performance levels on numerous procedural steps. Further validation work is needed to demonstrate transfer of training to the real world.

AIM:To identify, describe and detail the cognitive thought processes, decision-making, and physical actions involved in the preparation and successful performance of core interventional radiology procedures. MATERIALS AND METHODS:Five commonly performed core interventional radiology procedures were selected for cognitive task analysis. Several examples of each procedure being performed by consultant interventional radiologists were videoed. The videos of those procedures, and the steps required for successful outcome, were analysed by a psychologist and an interventional radiologist. Once a skeleton algorithm of the procedures was defined, further refinement was achieved using individual interview techniques with consultant interventional radiologists. Additionally a critique of each iteration of the established algorithm was sought from non-participating independent consultant interventional radiologists. RESULTS:Detailed task descriptions and decision protocols were developed for five interventional radiology procedures (arterial puncture, nephrostomy, venous access, biopsy-using both ultrasound and computed tomography, and percutaneous transhepatic cholangiogram). Identical tasks performed within these procedures were identified and standardized within the protocols. CONCLUSIONS:Complex procedures were broken down and their constituent processes identified. This might be suitable for use as a training protocol to provide a universally acceptable safe practice at the most fundamental level. It is envisaged that data collected in this way can be used as an educational resource for trainees and could provide the basis for a training curriculum in interventional radiology. It will direct trainees towards safe practice of the highest standard. It will also provide performance objectives of a simulator model.

The Virtual Environment Knee Arthroscopy Training System (VE-KATS) has been developed as a joint project between Orthopaedic Surgeons and Computer Scientists at the University of Hull. The objective is to develop a realistic surgical simulator, incorporating both simulated video from the arthroscopic camera and force feedback through the instruments.The small working volume during surgery, and the need to interact with both soft tissue and rigid joint surfaces, makes the provision of force feedback a particular challenge. In order to support the design of force feedback devices, and verify that the simulator accurately models behaviour seen during surgery, we have developed a system to measure forces and torque transmitted through the instruments.Force measurement experiments were conducted on both a synthetic model of the knee, and a cadaver pig knee. Participants, ranging from trainee level to experienced surgeon, carried out a number of pre-defined tasks, for which force data was acquired. The resulting data was analysed to identify the range of force and torque that must be reproduced by the simulator.

A comparison was made between two timetable formats: one (which is used extensively) represents the route vertically and is known as the Standard format; the other (which occurs less frequently) represents the route horizontally and is known as the Reflected format. The two formats were assessed in their basic versions and after being modified in ways which it was hoped would make them easier to use. To test the merits of the four timetable versions, 168 students were timed whilst using them to answer six questions which were representative of the uses to which timetables are put in real life. The results provided clear evidence for the superiority of the Reflected format after practice: the mean solution times for the Reflected versions being slightly (but not significantly) longer for the first questions, but significantly shorter for all the subsequent questions; the Reflected versions also producing fewer errors. Evidence from several sources suggested that the main reason for the superiority of the Reflected format was that it is easier to scan.