Alternative technologies for skills development

Performance assessment can only come from objective measurements of function. This requires a reliable repeatable method of evaluation of tasks. There are already a number of options available for skill assessment. Traditionally, those used included patients, cadavers, animal models and synthetic models.

2.5.1 Patients

There are ethical questions arising from teaching technical skills whilst operating on patients. Clearly, in teaching hospitals, it is not surprising that the training surgeons are, whilst under the appropriate level of supervision, performing most of the surgery. Consent for assessment of technical skill is difficult, since this implies the risk of lack of expertise in clinical practice.

There is no more valid a test than a real situation. There are questions of bias, true objectivity and the limitation of standardisation. It is not possible for an operation

to both be standard and realistic. To achieve regular assessment of technical competence, it is necessary also for evaluation to be performed in other environments that can be standardised. This should be complementary to those evaluations, which take place in operating theatres. The development of an educational framework support with individual learning agreements needs to be built into the process, affording users a clear record of progress as discussed in Chapter 7.

2.5.2 Cadavers

Whilst cadaveric material provides a 3D special relationship with the body when operating, it is not dynamic. There are issues to be considered surrounding the use of such material. Important issues are that cadaveric material cannot be re-used, that chemical agents such as formalin are required for fixation and that it is not possible to use this for training certain procedures such as laparoscopic surgery. For these and other anatomical reasons, such as variability of anatomy, cadavers are not appropriate for regular skills evaluation.

2.5.3 Animal models

Use of live animal models for surgical training in the UK is not permitted, unlike the United States and on the Continent of Europe. Whereas live animals offer the advantages of tactile validity, there are limitations. These include ethical issues and anatomical issues. Higher levels of animals are required to maximise the degree of transfer of skills learned from animals to operating on humans, with comparative anatomy. Animals are expensive to maintain, requiring specialised facilities which can be under threat of violent action from extreme groups, a problem not experienced when training on humans! Stotter, S, L. (10) produced freeze-dried animal tissue for bench- training of surgical skills with the developing anastomosis workshops (11) incorporating bench models into the training regime. This was an early example of ‘skills stations’ with clearly defined educational tasks.

2.5.4 Synthetic models

These have improved considerably over the years. They are still somewhat low fidelity and expensive. Individual models are typically over £500 each. They often contain re-usable components, which require replacement after each session typically at £40 - £50 each. It is this cost, and also the assertion that the models do not represent

anatomy well with respect to geometry and tactile properties, that has led to the need to explore computer-based simulations. At the level of basic surgical training, these may have a role for demonstration of core skills, such as triangulation of instruments and minimal access surgery. Some have been developed to the level required for higher surgical training for certain sub-skills. There is little evidence for the degree of transfer of learning skills from such models to human reality.

2.5.5 Models of skill assessment

Whatever tools are used to assist the training process, procedural lists are likely to be required as a record of the technical skills attained. This is explored in more detail in Chapter 7 when the role of the surgical logbook is reviewed in context. Such lists are surrogate for assessment of technical skill. They are ‘second hand’ analysis, reflecting the exposure to cases offered by the working environment. It is a measure of quantity and not quality. Training must be competency based. This implies that, under supervision, trainees will not be allowed to proceed to practising techniques beyond their abilities without supervision. Decreased level of supervision indicates that there is an increasing level of competence.

Some might argue (12) that it is only suchin-training evaluations that provide indicators of performance in real world situations. This is free of the biases that result from discrete examination episodes and this comprehensive system of day-to-day assessment should be the focus of effort. The approach of the Surgical Education Group at the University of Toronto to develop a bench model examination for surgical skills (referred to as the Objective Structured Assessment of Technical Skills - OSATS) (13) suggests that certain elements can be extracted from the procedures. Typical examinations involve rotating through 8 x 15 minute stations performing a technical task. They are marked using two scoring systems. The first is a task-specific checklist. The scoring rubric delineates whether a trainee has or has not performed an element of the procedure. The second is a global rating considering surgical behaviour. These are now administered yearly in Toronto and cover such issues as performing bowel anastomoses. Of interest to the developing shoulder simulation system is the global rating scale for operative performance, which is based upon performance irrespective of the level of previous training. This covers the following areas:

 Respect for tissue, knowledge of instruments and their handling

 Knowledge of specific procedure and flow of the operation

 Subjective appraisal of the overall performance and the final product quality The author acknowledges that such systems are labour intensive and expensive. However, they demonstrate a degree of validity with inter-station reliabilities of 0.8 being reported, adequate for making high-level decisions upon the trainee’s ability. Usually, there is a role for such systems and these have already been well established at the basic surgical training level. At the higher surgical training level, individual stations will continue to be integrated within the overall training infrastructure. Simulations may provide HST skills stations focusing upon the special sub-skills.