TY - JOUR
AU - Lewis, W G
AB - Abstract Background Certification of completion of training in general surgery in the UK requires demonstration of competence in index operations by means of three level 4 competence consultant-validated procedure-based assessments (PBAs). The aim of this study was to evaluate the trajectory of operative learning curves related to PBA performance levels for curriculum-defined indicative operations with respect to numbers performed and training time. Methods Logbook data from consecutive higher general surgical trainees were compared with PBA evaluations to determine the relationship between PBA performance level, operative experience, training time and indicative numbers. Learning curve gradients were calculated using the inverse trigonometric function of tan related to operative experience and training time. Results Eighty-four surgical trainees participated. Median caseload to achieve three level 4 competence assessments was 64 (range 18–110) for inguinal hernia, 83 (15–177) for emergency laparotomy, 87 (23–192) for laparoscopic cholecystectomy, 95 (22–209) for appendicectomy, 45 (17–111) for segmental colectomy and 16 (6–28) for Hartmann's procedure. Median learning curve gradients to achieve level 4 competence for emergency laparotomy were 15·3° and 33·7° by caseload and training time respectively, compared with 73·3° and 59·9° for Hartmann's procedure. Significant variance was observed in the gradients of all learning curves related to both the caseload between the first level 3 and the first level 4 PBA (P = 0·001), and between the first and third level 4 PBAs (P < 0·001). Conclusion Significant learning curve gradient variance was observed, with discrepancies between expected indicative operative numbers and the point at which competence was judged to have been achieved. Numbers of index operations to achieve certification of completion of training warrant further examination. Introduction Surgical education, training and curriculum development have witnessed unprecedented and extraordinary activity within the past decade in the UK1. European Working Time Directive2 regulations and Modernizing Medical Careers3, including a competency-based approach, have driven the requirement for clinical accountability and objective quantifiable educational outcomes and performance. Concerns regarding healthcare cost, quality and patient outcomes pose a threat to surgical training in the UK. The Intercollegiate Surgical Curriculum Programme (ISCP)4 in association with the General Medical Council (GMC)5 has reshaped modern surgical training, providing a platform for demonstrating clinical competence through completion of work-based assessments. Moreover, in 2013, the Joint Committee on Surgical Training published specific competency-based guidelines6 for the award of Certificate of Completion of Training (CCT). These stipulate a minimum total operative caseload of 1600, completion of sufficient procedure-based assessments (PBA) and a validated work-based assessment tool facilitating objective assessment of technical ability (Table 1) to demonstrate competence. The general surgery curriculum includes six key procedures (inguinal hernia repair, cholecystectomy, emergency laparotomy, appendicectomy, segmental colectomy and Hartmann's procedure), for which all trainees are required to demonstrate both a minimum indicative number and competence level, by means of three level 4 PBAs (3L4) by three different consultant assessors. Indicative numbers were originally set at a level corresponding to the first quartile of two historical cohorts of successful national CCT applicants7, and were intended as a guide, so that trainees might demonstrate a breadth of surgical experience. However, they have since proven a concern, because of fears that such levels are unachievable in all subspecialties and regional hospital training posts8. Table 1 Definition of procedure-based assessment scores PBA level . Definition . 0 Insufficient evidence observed to support a summary judgement 1 Unable to perform the procedure, or part observed, under supervision 2 Able to perform the procedure, or part observed, under supervision 3 Able to perform the procedure with minimum supervision (needed occasional help) 4 Competent to perform the procedure unsupervised (could deal with complications that arose) PBA level . Definition . 0 Insufficient evidence observed to support a summary judgement 1 Unable to perform the procedure, or part observed, under supervision 2 Able to perform the procedure, or part observed, under supervision 3 Able to perform the procedure with minimum supervision (needed occasional help) 4 Competent to perform the procedure unsupervised (could deal with complications that arose) Intercollegiate Surgical Curriculum Programme, version 9.0. PBA, procedure-based assessment. Open in new tab Table 1 Definition of procedure-based assessment scores PBA level . Definition . 0 Insufficient evidence observed to support a summary judgement 1 Unable to perform the procedure, or part observed, under supervision 2 Able to perform the procedure, or part observed, under supervision 3 Able to perform the procedure with minimum supervision (needed occasional help) 4 Competent to perform the procedure unsupervised (could deal with complications that arose) PBA level . Definition . 0 Insufficient evidence observed to support a summary judgement 1 Unable to perform the procedure, or part observed, under supervision 2 Able to perform the procedure, or part observed, under supervision 3 Able to perform the procedure with minimum supervision (needed occasional help) 4 Competent to perform the procedure unsupervised (could deal with complications that arose) Intercollegiate Surgical Curriculum Programme, version 9.0. PBA, procedure-based assessment. Open in new tab Learning curves are often referred to in the context of medical education, although their trajectories and natures are a matter of debate. Serial evaluation of operation-specific outcomes can plot a surgeon's position on a curve, with competence deemed to be the point at which the curve trajectory reaches an inflection point or plateau phase, consistent with satisfactory quality9. Curve trajectory or gradient equates to the rate of improvement of performance. The aim of this study was to evaluate the trajectory or gradient of incline between performance levels for general surgery curricular index procedures related to both operative experience, indicative numbers and time within a training programme, for higher surgical trainees within a UK deanery. Methods Consecutive national training number higher surgical trainees (HSTs) within a single UK deanery who had commenced the general surgery training programme between August 2007 and August 2016 were identified using the ISCP, and anonymized. Formal permission under the ISCP Data Governance Structure was not required because the study was in keeping with service evaluation. Individual HST reports were created using the Head of School report function (ISCP version 9.0), with particular reference to PBA assessment dates and competency levels for each of the six index operations: inguinal hernia repair, emergency laparotomy, laparoscopic cholecystectomy, appendicectomy, segmental colectomy and Hartmann's procedure. Access to trainee e-logbooks was obtained through the Head of School Director's page, and individual index operation reports were created to correlate with the specified date on which each PBA level was achieved. Plotting PBA levels against caseload created trainee learning curves for each index operation. The third level 4 PBA (3L4) was plotted as level 5. All axes were universalized to allow direct graphical comparison, and additional plots were created to relate PBA level to training time. All trainees were assumed to be commensurate with at least level 1 competence for each procedure at the start of their HST programme. Learning curve gradients related to PBA levels (first level 3 competence to first level 4 competence, and first to third level 4 competence) were calculated using standard trigonometric techniques (inverse function of tan)10, to allow arbitrary, objective comparison between procedures related to caseload and training time. Statistical analysis Statistical analysis appropriate for data with a non-normal distribution (Kruskal–Wallis and Mann–Whitney U tests) was performed using SPSS® version 23 (IBM, Armonk, New York, USA). Results Some 84 consecutive HSTs were included in the analysis, 44 of whom had achieved their 3L4 PBA for at least one of the six key index operations at time of review (Table 2). The majority of all 3L4 PBAs (121 of 160, 75·6 per cent) were achieved by trainees in their ST7 and ST8 year of training. Table 2 Total number of third level 4 competence procedure-based assessments achieved for each index operation by surgical trainee grade Surgical trainee grade . Inguinal hernia repair . Emergency laparotomy . Laparoscopic cholecystectomy . Appendicectomy . Segmental colectomy . Hartmann's procedure . ST3 0 0 0 1 0 0 ST4 0 0 0 4 0 0 ST5 2 0 3 7 0 0 ST6 5 1 4 10 1 1 ST7 6 6 7 5 1 1 ST8 17 21 16 17 11 13 Total 30 28 30 44 13 15 Surgical trainee grade . Inguinal hernia repair . Emergency laparotomy . Laparoscopic cholecystectomy . Appendicectomy . Segmental colectomy . Hartmann's procedure . ST3 0 0 0 1 0 0 ST4 0 0 0 4 0 0 ST5 2 0 3 7 0 0 ST6 5 1 4 10 1 1 ST7 6 6 7 5 1 1 ST8 17 21 16 17 11 13 Total 30 28 30 44 13 15 Open in new tab Table 2 Total number of third level 4 competence procedure-based assessments achieved for each index operation by surgical trainee grade Surgical trainee grade . Inguinal hernia repair . Emergency laparotomy . Laparoscopic cholecystectomy . Appendicectomy . Segmental colectomy . Hartmann's procedure . ST3 0 0 0 1 0 0 ST4 0 0 0 4 0 0 ST5 2 0 3 7 0 0 ST6 5 1 4 10 1 1 ST7 6 6 7 5 1 1 ST8 17 21 16 17 11 13 Total 30 28 30 44 13 15 Surgical trainee grade . Inguinal hernia repair . Emergency laparotomy . Laparoscopic cholecystectomy . Appendicectomy . Segmental colectomy . Hartmann's procedure . ST3 0 0 0 1 0 0 ST4 0 0 0 4 0 0 ST5 2 0 3 7 0 0 ST6 5 1 4 10 1 1 ST7 6 6 7 5 1 1 ST8 17 21 16 17 11 13 Total 30 28 30 44 13 15 Open in new tab Median caseload to achieve 3L4 competence was 64 (range 18–110) for inguinal hernia, 83 (15–177) for emergency laparotomy, 87 (23–192) for laparoscopic cholecystectomy, 95 (22–209) for appendicectomy, 45 (17–111) for segmental colectomy and 16 (6–28) for Hartmann's procedure. The median number of PBAs required to demonstrate 3L4 competence was 10 (range 6–16). Learning curves for all index operations relating competence (PBA level) to both case number and time are shown in Figs 1 and 2. The indicative number lay within the i.q.r. for inguinal hernia repair, emergency laparotomy and appendicectomy, and to the left of the i.q.r. for laparoscopic cholecystectomy, segmental colectomy and Hartmann's procedure, implying that competence for the latter three may not be achieved within current indicative number guidance. Fig. 1 Open in new tabDownload slide Operative learning curves for a,b inguinal hernia (30 trainees), c,d emergency laparotomy (28 trainees) and e,f laparoscopic cholecystectomy (30 trainees) by caseload (a, c, e) and time (b, d, f). The analysis for each procedure includes only trainees who had achieved their third level 4 competence (3L4) procedure-based assessment (PBA). Performance level 5 corresponds to 3L4 PBA Fig. 2 Open in new tabDownload slide Operative learning curves for a,b appendicectomy (44 trainees), c,d segmental colectotomy (13 trainees) and e,f Hartmann's procedure (15 trainees) by caseload (a, c, e) and time (b, d, f). The analysis for each procedure includes only trainees who had achieved their third level 4 competence (3L4) procedure-based assessment (PBA). Performance level 5 corresponds to 3L4 PBA Learning curve gradients for all index operations are shown in Table 3. Significant variance was observed in the gradients of all learning curves related to both the caseload between the first level 3 and the first level 4 PBA (P = 0·001), and between the first and third level 4 PBAs (P < 0·001). Significant variance was also observed in the gradients of all learning curves related to time between the first and third level 4 PBA (P = 0·025), but not related to the period between the first level 3 and first level 4 PBA (P = 0·732). Table 3 Learning curve gradients between first procedure-based assessment at level 3 competence and first at level 4 competence, and between first and third at level 4 competence . Incline (°) . . PBA level versus caseload . PBA level versus time . . First L3 to first L4 . First L4 to third L4 . First L3 to first L4 . First L4 to third L4 . Inguinal hernia repair 38·9 (10·0–84·3) 27·8 (13·1–78·7) 44·1 (11·9–85·3) 29·7 (15·6–80·5) Emergency laparotomy 19·1 (11·1–68·2) 15·3 (4·2–78·7) 36·9 (17·1–71·6) 33·7 (12·3–80·5) Laparoscopic cholecystectomy 19·1 (4·0–78·7) 15·3 (3·6–84·3) 36·9 (13·8–80·5) 33·7 (13·5–85·3) Appendicectomy 21·4 (5·5–84·3) 16·2 (5·3–84·3) 26·6 (12·1–85·2) 34·5 (10·1–85·2) Segemental colectomy 37·2 (9·2–84·3) 48·0 (9·5–78·7) 35·3 (8·5–63·4) 42·7 (13·5–76) Hartmann's procedure 61·2 (35·5–73·3) 73·3 (35·5–84·3) 32·8 (15·3–76·0) 59·9 (23·2–85·2) . Incline (°) . . PBA level versus caseload . PBA level versus time . . First L3 to first L4 . First L4 to third L4 . First L3 to first L4 . First L4 to third L4 . Inguinal hernia repair 38·9 (10·0–84·3) 27·8 (13·1–78·7) 44·1 (11·9–85·3) 29·7 (15·6–80·5) Emergency laparotomy 19·1 (11·1–68·2) 15·3 (4·2–78·7) 36·9 (17·1–71·6) 33·7 (12·3–80·5) Laparoscopic cholecystectomy 19·1 (4·0–78·7) 15·3 (3·6–84·3) 36·9 (13·8–80·5) 33·7 (13·5–85·3) Appendicectomy 21·4 (5·5–84·3) 16·2 (5·3–84·3) 26·6 (12·1–85·2) 34·5 (10·1–85·2) Segemental colectomy 37·2 (9·2–84·3) 48·0 (9·5–78·7) 35·3 (8·5–63·4) 42·7 (13·5–76) Hartmann's procedure 61·2 (35·5–73·3) 73·3 (35·5–84·3) 32·8 (15·3–76·0) 59·9 (23·2–85·2) Values are median (range). L3, level 3 competence; L4, level 4 competence. Open in new tab Table 3 Learning curve gradients between first procedure-based assessment at level 3 competence and first at level 4 competence, and between first and third at level 4 competence . Incline (°) . . PBA level versus caseload . PBA level versus time . . First L3 to first L4 . First L4 to third L4 . First L3 to first L4 . First L4 to third L4 . Inguinal hernia repair 38·9 (10·0–84·3) 27·8 (13·1–78·7) 44·1 (11·9–85·3) 29·7 (15·6–80·5) Emergency laparotomy 19·1 (11·1–68·2) 15·3 (4·2–78·7) 36·9 (17·1–71·6) 33·7 (12·3–80·5) Laparoscopic cholecystectomy 19·1 (4·0–78·7) 15·3 (3·6–84·3) 36·9 (13·8–80·5) 33·7 (13·5–85·3) Appendicectomy 21·4 (5·5–84·3) 16·2 (5·3–84·3) 26·6 (12·1–85·2) 34·5 (10·1–85·2) Segemental colectomy 37·2 (9·2–84·3) 48·0 (9·5–78·7) 35·3 (8·5–63·4) 42·7 (13·5–76) Hartmann's procedure 61·2 (35·5–73·3) 73·3 (35·5–84·3) 32·8 (15·3–76·0) 59·9 (23·2–85·2) . Incline (°) . . PBA level versus caseload . PBA level versus time . . First L3 to first L4 . First L4 to third L4 . First L3 to first L4 . First L4 to third L4 . Inguinal hernia repair 38·9 (10·0–84·3) 27·8 (13·1–78·7) 44·1 (11·9–85·3) 29·7 (15·6–80·5) Emergency laparotomy 19·1 (11·1–68·2) 15·3 (4·2–78·7) 36·9 (17·1–71·6) 33·7 (12·3–80·5) Laparoscopic cholecystectomy 19·1 (4·0–78·7) 15·3 (3·6–84·3) 36·9 (13·8–80·5) 33·7 (13·5–85·3) Appendicectomy 21·4 (5·5–84·3) 16·2 (5·3–84·3) 26·6 (12·1–85·2) 34·5 (10·1–85·2) Segemental colectomy 37·2 (9·2–84·3) 48·0 (9·5–78·7) 35·3 (8·5–63·4) 42·7 (13·5–76) Hartmann's procedure 61·2 (35·5–73·3) 73·3 (35·5–84·3) 32·8 (15·3–76·0) 59·9 (23·2–85·2) Values are median (range). L3, level 3 competence; L4, level 4 competence. Open in new tab Discussion Significant learning curve trajectory variance was observed in relation to both caseload and time across all procedures, ranging from 15·3° (emergency laparotomy) to 73·3° (Hartmann's procedure). The median number of PBAs required to demonstrate 3L4 competence was 10 (range 6–16), with competence for inguinal hernia repair, emergency laparotomy and appendicectomy achieved within the i.q.r. of experience expected, but not for laparoscopic cholecystectomy, segemental colectomy or Hartmann's procedure. Assessing a clinician's performance is challenging. Measures of learning surgical technique fall into two categories: surgical process and patient outcome. The relationship between surgeon experience and technical competence has long been controversial, and a number of recent reports have expressed concerns regarding indicative numbers as a representation of competence11,12. The operative achievements in the 2013 UK CCT cohort varied widely, with two-thirds of applicants achieving elective targets, but only half the requisite emergency experience, and 5 per cent non-operative targets8. The caseload required to demonstrate level 4 competence has been reported to vary over fourfold, and as a result the concept of competence ratios has been developed (ratio of case number at which 3L4 competence awarded to indicative number). This ratio has ranged from 0·76 (emergency laparotomy) to 3·4 (Hartmann's procedure)11. A hypothetical learning curve plot has four phases: commencement of training, followed by an ascending trajectory, with the gradient indicating how quickly performance improves; a third phase is reached when the procedure can be performed independently and competently9, with additional experience improving outcomes by small amounts, until a fourth phase and plateau is reached. A procedure with complex steps is often termed erroneously as having a steep learning curve. Steepness can equally relate to gaining height quickly, implying that skills are acquired rapidly because the procedure is simple. In fact, complex procedures are more likely to have gradual learning curves with small, stepwise improvements associated with each case, such that competence is achieved only after great experience or not at all. Learning curve trajectory shift, either left or right, equating to a more steep or shallow angle, or easier or more difficult procedures, will probably have multiple underlying reasons including: trainee clinical acumen and skill, trainer quality, training unit quality, trainee and trainer engagement with simulation of assessment processes, and the drive to reach a target. None of the learning curve plots in the present study, whether by caseload or time, reached a plateau phase once the 3L4 PBA had been achieved. Indeed, most trajectories appeared to steepen on approaching the 3L4 PBA, with the steepest curves witnessed for arguably the most complex procedures (subtotal colectomy and Hartmann's procedure), and in which the indicative number target fell to the left of the relevant i.q.r., implying a steeper than anticipated gradient. Alternatively, and possibly because of the more advanced skill set required to perform these operations, experienced trainees required fewer cases to demonstrate competence, in keeping with senior trainees acquiring evidence of competence more rapidly, as later training stages and CCT are approached. This study has a number of potential limitations. The data gathered were dependent on the accuracy with which trainees recorded logbook entries and assessment timing, which is related to trainee engagement. Learning curve trajectory is directly related to satisfactory logbook completion and PBA validation, and it is possible that the inflection points reported are inaccurate, if for example a trainee did not complete any PBAs until they or their trainer considered they were ready to attain level 4 competency. This would have the effect of producing an artificially steep learning curve and early achievement of competence. Moreover, once curriculum-defined competence had been gained, almost no trainees obtained further PBAs, making further trajectory evaluation impossible, which contrasts with comparable risk-rich professions such as aviation, where continued skill assessment is mandatory13. Attainment of PBAs for certain procedures is also likely to influence trajectory, with technically easier procedures such as appendicectomy and inguinal hernia repair often, ironically, being harder to obtain assessments for, as consultant trainers may not always be present in theatre. Certainly, however, it is now commonplace in the higher I and II phases of higher surgical training (ST5–6 and ST7–8 respectively) for a trainee to work with at least four trainer assessors electively and several more within the context of an emergency on-call rota, therefore increasing assessment opportunity. Overall performance for specific procedures may also depend on many factors, not least operative difficulty; it might be argued that a trainee assessed as 3L4 competent on three easy cases, may not necessarily be competent when confronted with more challenging cases. All of the HSTs were from a single UK deanery, and the data should be interpreted with caution, although 57 of the trainees (68 per cent) were appointed via national selection, which is subject to rigorous quality assurance. The influence of the x-axis scale in calculating the gradient of incline could result in unreproducible results if the format were changed, but axis uniformity with regard to procedure negates this effect and facilitates direct comparison. As CCT guidance was introduced in 2013, it is possible that poorer engagement by senior trainees (on an earlier 2010 curriculum) occurred and may have increased the median operative numbers needed to demonstrate competence. Some trainer assessors may have misinterpreted the scoring criteria, assuming level 4 competence to equate with expert rather than competent performance. Estimating any such effect is not possible retrospectively, and is mitigated by the fact that all trainers must declare their competence and have received PBA training. UK National Health Service consultant appointments occur after a defined training period and, although contemporary opinion suggests this may be shortened14,15, outcomes improve with experience and consultants will most likely be appointed based on a number of learning curves, short of the expert phase. Skill set development rather than number acquisition remains the challenge, and the will to employ teaching strategies, including simulation, that enhance and facilitate the development of universal competence. Skill acquisition requires further profiling. Allied to such initiatives, new consultants should recognize the need for post accreditation training, structured appraisal and senior mentors to facilitate professional development. Disclosure The authors declare no conflict of interest. Open in new tabDownload slide References 1 Akhtar K The role of simulation in developing surgical skills . Curr Rev Musculoskelet Med 2014 ; 7 : 155 – 160 . Google Scholar Crossref Search ADS PubMed WorldCat 2 European Parliament, Council of the European Union . Directive 2003/88/EC of the European Parliament and of the Council of 4 November 2003 concerning certain aspects of the organisation of working time . Official Journal of European Union 2001 ; Legislation 299 . OpenURL Placeholder Text WorldCat 3 Scottish Executive; Department of Health; Department of Health, Social Services and Public Safety; Welsh Assembly Government . Modernising Medical Careers: The Next Steps. The Future Shape of Foundation, Specialist and General Practice Training Programmes . Department of Health : London , 2004 . Google Scholar Google Preview OpenURL Placeholder Text WorldCat COPAC 4 Intercollegiate Surgical Curriculum Programme . http://www.iscp.ac.uk [accessed 20 February 2017 ]. 5 General Medical Council . 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Schaum's Outline of Theory and Problems of College Mathematics: Algebra, Discrete Mathematics, Trigonometry, Geometry, Introduction to Calculus (2nd edn) . McGraw-Hill : New York , 1992 . Google Scholar Google Preview OpenURL Placeholder Text WorldCat COPAC 11 Abdelrahman T , Long J, Egan R, Lewis WGL. Operative experience vs competence: a curriculum concordance and learning curve analysis . J Surg Educ 2016 ; 73 : 694 – 698 . Google Scholar Crossref Search ADS PubMed WorldCat 12 Siqueira JR , Gough MJ. Correlation between operative targets and competence for general surgical certification . Br J Surg 2016 ; 103 : 921 – 927 . Google Scholar Crossref Search ADS PubMed WorldCat 13 Federal Aviation Administration . Code of Federal Regulations, Part 61: Certification of Pilots, Flight Instructors and Ground Inspectors. Section 61.56; Flight Review . US Government Publishing Office : Washington DC , 2015 . Google Scholar Google Preview OpenURL Placeholder Text WorldCat COPAC 14 Royal College of Surgeons . Improving Surgical Training, Proposal for a Pilot Surgical Training Programme . Royal College of Surgeons : London , 2015 . Google Scholar Google Preview OpenURL Placeholder Text WorldCat COPAC 15 Greenaway D Shape of Training. Securing the Future of Excellent Patient Care: Final Report of the Independent Review Led by Professor David Greenaway ; 2013 . http://www.shapeoftraining.co.uk/static/documents/content/Shape_of_training_FINAL_Report.pdf_53977887.pdf [accessed 20 February 2017]. © 2017 BJS Society Ltd Published by John Wiley & Sons Ltd This article is published and distributed under the terms of the Oxford University Press, Standard Journals Publication Model (https://academic.oup.com/journals/pages/open_access/funder_policies/chorus/standard_publication_model) © 2017 BJS Society Ltd Published by John Wiley & Sons Ltd
TI - Operative learning curve trajectory in a cohort of surgical trainees
JO - British Journal of Surgery
DO - 10.1002/bjs.10584
DA - 2017-08-07
UR - https://www.deepdyve.com/lp/oxford-university-press/operative-learning-curve-trajectory-in-a-cohort-of-surgical-trainees-Q2D4D4Du9Z
SP - 1405
EP - 1411
VL - 104
IS - 10
DP - DeepDyve
ER -