The impact of external feedback on computer-assisted learning for surgical technical skill training

Comprehensive training curricula for minimally invasive surgery

BACKGROUND

The unique skill set required for minimally invasive surgery has in part contributed to a certain portion of surgical residency training transitioning from the operating room to the surgical skills laboratory. Simulation lends itself well as a method to shorten the learning curve for minimally invasive surgery by allowing trainees to practice the unique motor skills required for this type of surgery in a safe, structured environment. Although a significant amount of important work has been done to validate simulators as viable systems for teaching technical skills outside the operating room, the next step is to integrate simulation training into a comprehensive curriculum.

OBJECTIVES

This narrative review aims to synthesize the evidence and educational theories underlining curricula development for technical skills both in a broad context and specifically as it pertains to minimally invasive surgery.

FINDINGS

The review highlights the critical aspects of simulation training, such as the effective provision of feedback, deliberate practice, training to proficiency, the opportunity to practice at varying levels of difficulty, and the inclusion of both cognitive teaching and hands-on training. In addition, frameworks for integrating simulation training into a comprehensive curriculum are described. Finally, existing curricula on both laparoscopic box trainers and virtual reality simulators are critically evaluated.

Impact of group size on the effectiveness of a resuscitation simulation curriculum for medical students

BACKGROUND

Simulation requires involvement from participants. However, it is unknown to what extent simulation effectiveness is a function of the number of participants.

PURPOSE

This study assessed the impact of varying group size on medical students' subjective experience of simulation and on postsimulation exam performance.

METHODS

Medical students were randomly assigned to groups of 2, 3, or 4. Retrospective assessment was done through a survey assessing confidence and knowledge as it relates to resuscitation and statements related to group size. Performance on a postsimulation exam was analyzed.

RESULTS

There were significant increases in students' confidence and knowledge following simulation. There were no significant differences in student perception of the effectiveness or realism of the simulation or in performance on the postsimulation exam as a function of group size.

CONCLUSIONS

Students feel that simulation is an effective way to learn medical knowledge. Varying group size had no effect on students' subjective experience or exam performance.

Assessment of early learning curves among nurses and physicians using a high-fidelity virtual-reality colonoscopy simulator

BACKGROUND

Recently, it has been suggested that nurses can perform diagnostic endoscopy procedures, which traditionally have been a physician's responsibility. The existing studies concerning quality of sigmoidoscopy performed by nurses are small, used assessment tools with insufficient validation and to date there is very little knowledge of the learning curve patterns for physicians and nurses. The aim of a present study was to assess early learning curves on a virtual-reality colonoscopy simulator of untrained residents as compared with that of nurses with and without endoscopy assistance experience.

MATERIALS AND METHODS

Thirty subjects were included in the study: 10 female residents (median age 30.5 years) without colonoscopy experience, 10 female nurses (median age 27.5 years) without endoscopy assistance experience and 10 female nurses (median age 42 years) with endoscopy assistance experience. All participants performed 10 repetitions of task 6 from the "Introduction" colonoscopy module of the Accu Touch Endoscopy simulator. Eight experienced colonoscopists performed three repetitions of task 6 in order to provide the reference expert level of performance.

RESULTS

All subjects completed the virtual colonoscopy without complications. Significant differences existed between residents and nurses with respect to time to complete the procedure. Residents and nurses showed similar learning curve patterns. There were not significant differences between the groups in terms of volume of insufflated air, percentage of time without discomfort, and percentage of mucosa seen. None of the trainee groups achieved expert proficiency level in terms of time and amount of insufflated air by the tenth repetition.

CONCLUSIONS

Nurses performed virtual colonoscopy as accurately and safely as residents. Although the residents performed significantly faster, time differences showed a tendency towards decreasing, and appraisement of the numeric time differences seemed of minor practical importance. From a technical point of view this indicates that nurses may learn to perform colonoscopy after appropriate training.

Feedback in laparoscopic skills acquisition: an observational study during a basic skills training course

This study aimed to obtain insight in the effect of expert feedback during a basic laparoscopic skills training course for residents. A questionnaire was held among participants regarding provided feedback and the self-perceived laparoscopic skills improvement. The participants (n = 24) who completed the questionnaire were in their first to fifth postgraduate year. Most feedback was directed at intracorporeal knot tying (47% reported extensive feedback), while camera navigation and body positioning received the least feedback (40% and 43%, respectively, responded to have received no feedback at all). After the course, the self-perceived competence in intracorporeal knot tying and cutting had improved significantly, while camera navigation, body positioning, pointing, and grasping tasks did not improve. In conclusion, most benefit from expert feedback can be obtained at the start of the learning curve. Therefore, the basic laparoscopic skills course should be attended early in residency. Additionally, it is crucial that training objectives are clear prior to a course for both the expert and the trainee, in order to focus the feedback on all training objectives.

Factors associated with physiotherapists' interest in cardiorespiratory continuing education using computer-assisted learning: a survey

PURPOSE

To determine factors associated with Canadian physiotherapists' interest in undertaking continuing education in various cardiorespiratory content areas and their willingness to complete a portion of study within each of these content areas via computer-assisted learning (CAL).

METHODS

In a six-page mailed questionnaire, 1,426 potential participants were asked to indicate their interest in 11 cardiorespiratory content areas, their continuing-education preferences, and their access and willingness to do continuing education by CAL. Demographic data were also collected from respondents.

RESULTS

Respondents included 285 physiotherapists from cardiorespiratory interest groups (CRGs) and 447 from the licensing bodies' sample (overall response rate = 56%). Physiotherapists in public employment and practice areas other than orthopaedics had increased interest in all cardiorespiratory content areas except Exercise Physiology. Membership in a CRG increased their likelihood to be willing to learn the cardiorespiratory content area via CAL.

CONCLUSIONS

In developing content and determining the accessibility of cardiorespiratory continuing education, educators should consider the type of employer and area of practice of interested attendees as well as the lack of willingness to use CAL by those not involved in CRGs.

The new ACS/APDS Skills Curriculum: moving the learning curve out of the operating room

Surgical education has dramatically changed in response to numerous constraints placed on residency programs, but a substantial gap in uniform practices exist, especially in the area of skills laboratory availability and usage. Simulation-based training has gained significant momentum and will be a requirement for residencies in the near future. In response, the American College of Surgeons and the Association of Program Directors in Surgery have formed a Surgical Skills Curriculum Task Force with the aim of establishing a National Skills Curriculum. The first of three phases will undergo implementation in 2007, with subsequent phases scheduled for launch in 2008. The curriculum has been carefully structured and designed by content experts to enhance resident training through reproducible simulations, with verification of proficiency before operative experience. Free-of-charge distribution is planned through a web-based platform, and widespread adoption is encouraged. In the future, these simulation-based strategies may be useful in assuring the competency of practicing surgeons and for credentialing purposes.

A comparison of faculty and resident perception of resident learning needs in the operating room

OBJECTIVES

The purpose of this study was to gain an understanding of faculty and resident perception of residents' learning needs regarding operative management. Our hypothesis is that surgical faculty and residents have significantly different perceptions of residents' learning needs.

DESIGN

This study used a 27-item survey designed to determine (1) the extent to which traditional learning resources are used by residents when preparing for cases in the operating room, (2) which Web-based resources residents use for operating room preparation, and (3) which operative management topics residents were deficient in despite preoperative preparation.

SETTING

The settings for this study were the exhibit hall area during the 90th American College of Surgeons' Clinical Congress Meeting and a weekly resident conference.

PARTICIPANTS

Participants for this study included a convenience sample of faculty and resident volunteers from the Clinical Congress and residents of our program (N = 246).

RESULTS

On a scale of 1-5, with 5 indicating frequent use, residents rated their most frequently used resources as Major Surgical Texts (3.99) and Advice from colleagues (3.97). The top 3 operative management topics residents felt least prepared for after studying were "instrument use" (67.7%), "suture selection" (65.3%), and "operative field exposure" (50.0%). The top 3 operative management topics faculty felt residents were least prepared for were "anatomy" (73.9%), "natural history of disease" (73.9%), and "procedure choices" (69.6%). Chi-square analysis comparing faculty and resident perceptions of resident learning needs showed significant differences (p < 0.05) in 12 of the 12 operative management topics rated.

CONCLUSION

A critical step in guiding development and proper use of learning technologies for surgical education is the conduct of needs assessments. The disparity between faculty and resident perception of residents' learning needs in the operating room underscores the need for residents to be included in needs assessments relating to surgical training.

A cost-effective proficiency-based knot-tying and suturing curriculum for residency programs

BACKGROUND

The purpose of this study was to develop a structured open skills curriculum for knot-tying and suturing using expert-derived performance goals and to examine its feasibility, cost-effectiveness, and construct validity.

METHODS

Using commercially available bench models, 11 standardized tasks (ranging from 2-handed knot-tying to running subcuticular closure) were developed and scored using previously validated metrics based on time and errors. Expert performance was used to establish training endpoints and to create a video tutorial. PGY 1 residents (n = 4) were enrolled in a prospective Institutional Review Board-approved pilot study that included proctored orientation and baseline testing, self-training to proficiency, and proctored post-testing (conducted over a 4-wk period). Baseline trainee scores were compared with expert scores to evaluate construct validity.

RESULTS

The 11 tasks proved relatively robust, and excellent feedback was obtained from the trainees regarding educational benefit. Overall, trainees performed 144 +/- 33 repetitions over 11 +/- 2 h. Trainees achieved proficiency for 4.6% of the 11 tasks at baseline, 91% during training, and 84% at post-testing. Trainees demonstrated significant improvement from baseline to post-testing, validating skill acquisition; baseline trainee and expert performance were significantly different, confirming construct validity. Curriculum development cost $1200 and required 72 man-hours. Incremental training cost less than $12 per participant and required 8 man-hours per rotation using the video-based self-practice curriculum. In response to participant feedback, two of the 11 tasks were modified and a twelfth task was added.

CONCLUSIONS

This curriculum is cost-effective, feasible within the context of residency training, educationally beneficial, and demonstrates construct validity. More widespread adoption of standardized, validated skills curricula such as this by residency programs is warranted.

Limited feedback and video tutorials optimize learning and resource utilization during laparoscopic simulator training

BACKGROUND

The purpose of this study was to determine the impact of instructor feedback and video tutorials on skill acquisition during proficiency-based laparoscopic suturing training.

METHODS

Performance data from a prospectively maintained database were reviewed for three groups of novices (n = 34 medical students) who completed the same proficiency-based laparoscopic suturing curriculum on a Fundamentals of Laparoscopic Surgery-type videotrainer model as part of two separate institutional review board-approved, randomized controlled trials. Group I (n = 9) watched the video tutorial once and received intense feedback during each training session; Group II (n = 13) watched the video tutorial once and received limited feedback (<10 min per session); Group III (n = 12) watched the video tutorial several times and also received limited feedback (<10 min per session). Feedback was given by the same instructor and was quantified on a 0 (none) to 4 (extensive) Likert scale.

RESULTS

Baseline characteristics were similar for all groups. All participants achieved the proficiency level (512) on two consecutive attempts. Group III required the shortest training time and number of repetitions to reach proficiency, with statistically significant differences compared with Group I (P < 0.02). This strategy led to a cost savings of $139 per trainee.

CONCLUSIONS

Limited instructor feedback appears to be superior to intense feedback during proficiency-based laparoscopic simulator training. Coupled with video tutorials, this type of feedback may accelerate learning and improve resource utilization by minimizing the need for instructor involvement.

Teaching suturing and knot-tying skills to medical students: A randomized controlled study comparing computer-based video instruction and (concurrent and summary) expert feedback

BACKGROUND

We carried out a prospective, randomized, 4-arm study including control arm, blinding of examiners to determine effectiveness of computer-based video instruction (CBVI) and different types of expert feedback (concurrent and summary) on learning of a basic technical skill.

METHODS

Using bench models, participants were pre-tested on a suturing and instrument knot-tying skill after viewing an instructional video. The students were subsequently assigned randomly to 4 practice conditions: no additional intervention (control), self study with CBVI, expert feedback during practice trials (concurrent feedback), and expert feedback after practice trials (summary feedback). All participants underwent 19 trials of practice, over 1 hour, in their assigned training condition. The effectiveness of training was assessed both at an immediate post-test and 1 month later at a retention test. Performance was evaluated using both expert-based (Global Rating Scores) and computer-based assessment (Hand Motion Analysis). Data were analyzed using repeated-measures ANOVA.

RESULTS

There were no differences in GRS between groups at pre-test. The CBVI, concurrent feedback and summary feedback methods were equally effective initially for the instruction of this basic technical skill to naive medical students and displayed better performance than control (control, 12.71 [10.79 to 14.62]; CBVI, 16.39 [14.38 to 18.40]; concurrent, 16.97 [15.79 to 18.15]; summary, 16.09 [13.57 to 18.62]; P < .001 each). At retention. however, only CBVI and summary feedback groups retained superior suturing and knot-tying performance versus control (control, 8.13 [6.94 to 9.85]; CBVI, 11.92 [10.19 to 14.99] P = .037; concurrent, 9.80 [8.55 to 13.45] P = .635; summary, 111.19 [10.27 to 14.29] P = .037). Hand motion data displayed a similar pattern of results. There were no group differences in the rate of learning (P > .05).

CONCLUSION

Our study showed that CBVI can be as effective as summary expert feedback in the instruction of basic technical skills to medical students. Thoughtfully incorporated into technical curricula, CBVI can make efficient use of faculty time and serve as a useful pedagogic adjunct for basic skills training. Additionally, our study provides evidence supporting an increased role of summary feedback to effectively train novices in technical skills.

Laboratory-based vascular anastomosis training: A randomized controlled trial evaluating the effects of bench model fidelity and level of training on skill acquisition

BACKGROUND

Although there is growing evidence that practice on bench model simulators can improve the acquisition of technical skill in surgery, the degree to which these models have to approximate real-world conditions (model fidelity) to optimize learning is unclear. Previous research suggests that low-fidelity models may be adequate for novice learners. The purpose of this study was to assess the effect of model fidelity and surgical expertise on the acquisition of vascular anastomosis skill.

METHODS

Twenty-seven surgical residents participated in this institutional review board-approved study. Junior residents (postgraduate year 1 and 2) and senior residents (postgraduate year 4 or higher) were randomized into two groups: low-fidelity (n = 13) and high-fidelity (n = 14) model training. Both groups were given a 3-hour hands-on training session: the low-fidelity group used plastic models, and the high-fidelity group used human cadaver arms (brachial arteries) to practice graft-to-arterial anastomosis. One week later, all subjects participated in an animal laboratory in which they performed a single vascular anastomosis on a live, anesthetized pig (femoral artery). A blinded vascular surgeon scored candidate performance in the animal laboratory by using previously validated end points, including a checklist and final product analysis score.

RESULTS

Acquisition of skill was significantly affected by model fidelity and level of training as measured by both the checklist (P = .03) and final product analysis (P = .01; Kruskal-Wallis). Specifically, junior residents practicing on high-fidelity models scored better on the checklist (P = .05) and final product analysis (P = .04). Senior residents practicing on high-fidelity models scored better on final product analysis (P < .05).

CONCLUSIONS

Training in the laboratory does improve skill when assessed in a realistic setting. Both expertise groups showed better skill transfer from the bench model to live animals when practicing on high-fidelity models. For vascular anastomosis, it is important to provide appropriate model fidelity for trainees of different abilities to optimize the effectiveness of bench model training.

Surgical skill acquisition with self-directed practice using computer-based video training

BACKGROUND

Computer-based video training (CBVT) provides flexible opportunities for surgical trainees to learn fundamental technical skills, but may be ineffective in self-directed practice settings because of poor trainee self-assessment. This study examined whether CBVT is effective in a self-directed learning environment among novice trainees.

METHODS

Thirty novice trainees used CBVT to learn the 1-handed square knot while self-assessing their proficiency every 3 minutes. On reaching self-assessed skill proficiency, trainees were randomized to either cease practice or to complete additional practice. Performance was evaluated with computer and expert-based measures during practice and on pretests, posttests, and 1-week retention tests.

RESULTS

Analyses revealed performance improvements for both groups (all P < .05), but no differences between the 2 groups (all P > .05) on all tests.

CONCLUSIONS

CBVT for the 1-handed square knot is effective in a self-directed learning environment among novices. This lends support to the implementation of self-directed digital media-based learning within surgical curricula.

Verbal feedback from an expert is more effective than self-accessed feedback about motion efficiency in learning new surgical skills

BACKGROUND

Teaching of technical surgical skills to undergraduate medical students in a laboratory setting away from the patient is not common practice. Because of the large volume of students and shortage of available teaching faculty new methods of teaching must be developed for this group of trainees. In this study we examined the effectiveness of computer-based video training, different types of computer-based motion efficiency feedback (with and without expert criteria), and expert feedback on learning of a basic technical skill in medical students.

METHODS

Forty-five junior medical students were randomized into 3 groups and learned suturing and knot-tying skills. Group A received computer-generated feedback about the economy of their movements. Group B received the same motion economy feedback, as well as expert reference values. Group C received verbal feedback from an expert. All groups were pre-tested, allowed 18 practice trials, and post-tested, and their skill retention was retested after 1 month. Performance was assessed by expert analysis using an objective structured analysis of technical skill and by computer analysis (Imperial College Surgical Assessment Device [ICSAD]).

RESULTS

All groups showed improvement from pre-test to post-test. However, only group C showed retention of skill on delayed performance testing.

CONCLUSIONS

Verbal feedback from an expert instructor led to lasting improvements in technical skills performance. Providing information about motion efficiency did not lead to similar improvements.

Teaching surgical skills: what kind of practice makes perfect?: a randomized, controlled trial

OBJECTIVE

Surgical skills laboratories have become an important venue for early skill acquisition. The principles that govern training in this novel educational environment remain largely unknown; the commonest method of training, especially for continuing medical education (CME), is a single multihour event. This study addresses the impact of an alternative method, where learning is distributed over a number of training sessions. The acquisition and transfer of a new skill to a life-like model is assessed.

METHODS

Thirty-eight junior surgical residents, randomly assigned to either massed (1 day) or distributed (weekly) practice regimens, were taught a new skill (microvascular anastomosis). Each group spent the same amount of time in practice. Performance was assessed pretraining, immediately post-training, and 1 month post-training. The ultimate test of anastomotic skill was assessed with a transfer test to a live, anesthetized rat. Previously validated computer-based and expert-based outcome measures were used. In addition, clinically relevant outcomes were assessed.

RESULTS

Both groups showed immediate improvement in performance, but the distributed group performed significantly better on the retention test in most outcome measures (time, number of hand movements, and expert global ratings; all P values <0.05). The distributed group also outperformed the massed group on the live rat anastomosis in all expert-based measures (global ratings, checklist score, final product analysis, competency for OR; all P values <0.05).

CONCLUSIONS

Our current model of training surgical skills using short courses (for both CME and structured residency curricula) may be suboptimal. Residents retain and transfer skills better if taught in a distributed manner. Despite the greater logistical challenge, we need to restructure training schedules to allow for distributed practice.

An investigation of medical student reactions to feedback: a randomised controlled trial

BACKGROUND

Medical educators have indicated that feedback is one of the main catalysts required for performance improvement. However, medical students appear to be persistently dissatisfied with the feedback that they receive. The purpose of this study was to evaluate learning outcomes and perceptions in students who received feedback compared to those who received general compliments.

METHODS

All subjects received identical instruction on two-handed surgical knot-tying. Group 1 received specific, constructive feedback on how to improve their knot-tying skill. Group 2 received only general compliments. Performance was videotaped before and after instruction and after feedback. Subjects completed the study by indicating their global level of satisfaction. Three faculty evaluators observed and scored blinded videotapes of each performance. Intra-observer agreement among expert ratings of performance was calculated using 2-way random effects intraclass correlation (ICC) methods. Satisfaction scores and performance scores were compared using paired samples t-tests and independent samples t-tests.

RESULTS

Performance data from 33 subjects were analysed. Inter-rater reliability exceeded 0.8 for ratings of pre-test, pre-intervention and post-intervention performances. The average performance of students who received specific feedback improved (21.98 versus 15.87, P<0.001), whereas there was no significant change in the performance score in the group who received only compliments (17.00 versus 15.39, P=0.181) The average satisfaction rating in the group that received compliments was significantly higher than the group that received feedback (6.00 versus 5.00, P=0.005).

DISCUSSION

Student satisfaction is not an accurate measure of the quality of feedback. It appears that satisfaction ratings respond to praise more than feedback, while learning is more a function of feedback.

Impact of the 80-hour work week on resident emergency operative experience

BACKGROUND

The goal of this study was to analyze the impact of the 80-hour work week on the emergency operative experience of surgical residents.

METHODS

A 2-year retrospective comparison of the operative experience in emergency abdominal procedures of postgraduate year 4 and 5 residents in a city hospital before (group 1) and after (group 2) duty hour restriction.

RESULTS

There was no difference between groups in the mean number of procedures performed as the primary surgeon, but group 2 showed a 40% decrease in technically advanced procedures with a 44% increase in basic procedures. The study also demonstrated a 54% decrease in the operative volume as first assistant. Operative continuity of care by residents decreased from 60% to 26% of cases.

CONCLUSIONS

The ACGME regulatory environment is adversely affecting the emergency operative experience of surgical residents. Our findings underscore the need to develop alternative methods to augment the residents' operative experience.

A RIME perspective on the quality and relevance of current and future medical education research

In this article, the authors consider the quality and relevance of current and future medical education research by (1) presenting a framework for medical education research and reviewing basic principles of "good" empirical work, (2) extending the discussion of principles to "best practices," (3) considering the distinctive features of medical education that present challenges to the researcher, and (4) discussing opportunities for expanding the scope and influence of medical education research. Their audience is intended to be clinicians involved in education, deans and associate deans who create and direct educational curricula and processes, and those from offices critical to the educational mission such as admissions, student services and financial aid, as well as medical education researchers. The authors argue that the quality and relevance of current work can be enhanced when research is situated within a general framework and questions are asked that are based on literature and theory and push the field toward new knowledge. Obviously methods and designs must be appropriate and well-executed and sufficient data must be gathered. Multiple studies are highlighted that showcase the rigor and creativity associated with excellent quality work. However, good research is not without its challenges, most notably short timelines and the need to work within an ever-changing real-life educational environment. Most important, the field of medical education research has many opportunities to increase its impact and advance its quest to study important learners' behaviors and patients' outcomes. Programs to train and collaborate with clinical and administrative colleagues, as well as researchers in other fields, have great potential to improve the quality of research in the field.

The effectiveness of video feedback in the acquisition of orthopedic technical skills

BACKGROUND

The addition of video feedback to bench model training offers residents the opportunity to see themselves perform a surgical task. Videotaped feedback therefore promotes self-evaluation, a critical learning skill, and also has the potential to influence how a resident executes a skill once they have had the opportunity to see themselves perform the task.

METHODS

Twenty-nine surgical residents were video recorded while performing three technical skills. They then were randomly assigned to receive either no feedback, video feedback alone, or video feedback with the help of an expert, an orthopedic surgeon. The surgical task was then repeated. Orthopedic surgeons evaluated the videotapes using the global rating scale and technical checklist form.

RESULTS

One-way between-subject analysis of variance comparing the pretest and post-test difference scores on three different measures for each of the three tasks revealed no statistically significant differences. After controlling for rater variance, the global rating scores across the three surgical tasks did not reveal any statistically significant differences.

CONCLUSIONS

This study failed to demonstrate an improvement in technical skills based on utilization of video feedback.

Training for Infrainguinal Bypass Surgery

BACKGROUND

Despite satisfactory results for surgery performed by trainees, vascular surgeons need to improve training methods to ensure that aspiring surgeons are adequately trained with less clinical exposure during fewer dedicated years of training.

OBJECTIVES

To review the wide range of workshop, laboratory and seminar-room based methods available to train for the diverse range of skills required for distal arterial revascularisation. Training methods include anastomotic suturing skills with bench-top training apparatus, working with realistic plastic models and prosthetic conduits, cadaveric dissections and virtual-reality simulations. Many of these also provide excellent opportunities for objective assessment of technical skills and trainees' progress.

DESIGN AND METHODS

A review of the literature on surgical education, surgical skills training and assessment. An evaluation of some of the apparatus, facilities, training curricula and courses, currently available to European trainees, is carried out.

CONCLUSIONS

Many methods are now available to allow focused training for particular skills in non-clinical settings. Objective tools are also available that allow assessment of trainees at many levels or practicing surgeons. These technical skills assessment methods are important for trainees and surgeons who, in the future, will increasingly need to demonstrate competence in vascular surgery.

Self-assessment in simulation-based surgical skills training

BACKGROUND

Simulation-based training provides minimal feedback and relies heavily on self-assessment. Research has shown medical trainees are poor self-assessors. The purpose of this study was to examine trainees' ability to self-assess technical skills using a simulation-trainer.

METHODS

Twenty-one medical students performed 10 repetitions of a simulated task. After each repetition they estimated their time and errors made. These were compared with the simulator data.

RESULTS

Task time (P < 0.0001) and errors made (P < 0.0001) improved with repetition. Both self-assessment curves reflected their actual performance curves (P < 0.0001). Self-assessment of time did not improve in accuracy (P = 0.26) but error estimation did (P = 0.01) when compared with actual performance.

CONCLUSIONS

Novices demonstrated improved skill acquisition using simulation. Their estimates of performance and accuracy of error estimation improved with repetition. Clearly, practice enhances technical skill self-assessment. These results support the notion of self-directed skills training and could have significant implications for residency training programs.

A role for error training in surgical technical skill instruction and evaluation

BACKGROUND

During the evaluation of many instances of the same basic surgical skill, we observed that there were several errors that occurred frequently. Two studies were undertaken to examine the use of these errors for improving the instruction and evaluation of the skill.

MATERIALS AND METHODS

For both studies, two types of rater training videotapes were developed. One involved the use of examples of common errors (error) and the other demonstrated the skill being performed correctly (correct). A testing videotape was created consisting of 24 performances of the skill that ranged in quality of the performance. The first study was designed to assess the impact of error instruction on skill acquisition. In this study, a group of 30 senior medical students were randomly assigned to one of four different training groups: none, error only, correct only, and error+correct. Subjects were videotaped performing the skill before and after the training and three experts evaluated these performances independently using a 7-point rating scale. The second study was designed to assess the impact of error training on skill evaluation and was done using both novice and expert raters. The same group of 30 senior medical students used in the first study was used as novice raters. Following training in one of the four training groups, each subject rated the 24 performances on the testing videotape and interrater reliability was assessed for each group. Surgical faculty served as expert raters in this study and were randomly assigned to receive either error training or no training. Each subject viewed the testing videotape, rating the performances and giving "feedback" commentary. Interrater reliability was calculated for the two groups and the precision of the feedback was assessed.

RESULTS

Significant improvement in posttest performance scores was seen only in the "error+correct" training group. Interrater reliability was somewhat lower for the "correct only" and "error only" training groups in both the student and faculty studies. Faculty raters receiving error training had a higher proportion of specific comments than the group that received no training although this difference was not statistically significant.

CONCLUSIONS

Instruction about common errors, when combined with instruction about the correct performance enhanced the acquisition of this surgical skill. This suggests a role for the use of errors in surgical technical skill instruction. Our study provides no support for a role for error training in improving skill evaluation.

Telerobotic laparoscopic cholecystectomy: initial clinical experience with 25 patients

OBJECTIVE

To determine the safety and feasibility of performing telerobotic laparoscopic cholecystectomies. This will serve as a preliminary step toward the integration of computer-rendered three-dimensional preoperative imaging studies of anatomy and pathology onto the patient's own anatomy during surgery.

SUMMARY BACKGROUND DATA

Computer-assisted surgery (CAS) increases the surgeon's dexterity and precision during minimally invasive surgery, especially when using microinstruments. Clinical trials have shown the improved microsurgical precision afforded by CAS in the minimally invasive setting in cardiac and gynecologic surgery. Future applications would allow integration of preoperative data and augmented-reality simulation onto the actual procedure.

METHODS

Beginning in September 1999, CAS was used to perform cholecystectomies on 25 patients at a single medical center in this nonrandomized, prospective study. The operations were performed by one of two surgeons who had previous laboratory experience using the computer interface. The entire dissection was performed by the surgeon, who remained at a distance from the patient but in the same operating room. The operation was evaluated according to time of dissection, time of assembly/disassembly of robot, complications, immediate postoperative course, and short-term follow-up.

RESULTS

Twenty of the 25 patients had symptomatic cholelithiasis, 1 had a gallbladder polyp, and 4 had acute cholecystitis. Twenty-four of the 25 laparoscopic cholecystectomies were successfully completed by CAS. There was one conversion to conventional laparoscopic cholecystectomy. Set-up and takedown of the robotic arms took a median of 18 minutes. The median operative time for dissection and the overall operative time were 25 and 108 minutes, respectively. There were no intraoperative complications. There was one postoperative complication of a suspected pulmonary embolus, which was treated with anticoagulation. All patients were tolerating diet at discharge.

CONCLUSIONS

Laparoscopic cholecystectomy performed by CAS is safe and feasible, with operative times and patient recovery similar to those of conventional laparoscopy. At present, CAS cholecystectomy offers no obvious advantages to patients, but the potential advantages of CAS lie in its ability to convert the surgical act into digitized data. This digitized format can then interface with other forms of digitized data, such as pre- or intraoperative imaging studies, or be transmitted over a distance. This has the potential to revolutionize the way surgery is performed.