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Amer MA, Herbison GP, Grainger SH, Khoo CH, Smith MD, McCall JL. A meta-epidemiological study of bias in randomized clinical trials of open and laparoscopic surgery. Br J Surg 2021; 108:477-483. [PMID: 33778858 DOI: 10.1093/bjs/znab035] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Revised: 11/15/2020] [Accepted: 01/17/2021] [Indexed: 11/12/2022]
Abstract
BACKGROUND Blinding, random sequence generation, and allocation concealment are established strategies to minimize bias in RCTs. Meta-epidemiological studies of drug trials have demonstrated exaggerated treatment effects in RCTs where such methods were not employed. As blinding is more difficult in surgical trials it is important to determine whether this applies to them. The study aimed to investigate this using systematic meta-epidemiological methods. METHOD The Cochrane Database of Systematic Reviews was searched for systematic reviews of RCTs that compared laparoscopic and open abdominal surgical procedures. Each review was then scrutinized to determine whether at least one of the included trials was blinded. Eligible reviews were updated and individual RCTs retrieved. Extracted data included the primary outcomes of interest (length of stay and complications), secondary outcomes and a risk of bias assessment. A multistep meta-regression analysis was then performed to obtain an overall difference in the reported outcome differences between trials that employed each bias-minimization strategy, and those that did not. RESULTS Some 316 RCTs were included, reporting on eight different procedures. Patient-blinded RCTs reported a smaller difference in length of stay between laparoscopic and open groups (difference of standardized mean differences -0·36 (95 per cent c.i. -0·73 to 0·00)) and complications (ratio of odds ratios 0·76 (95 per cent c.i. 0·61 to 0·93)). Blinding of postoperative carers and outcome assessors had similar effects. CONCLUSION Lack of blinding significantly altered the treatment effect estimates of RCTs comparing laparoscopic and open surgery. Blinding should be implemented in surgical RCTs where possible to avoid systematic bias.
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Affiliation(s)
- M A Amer
- Department of Surgical Sciences, Dunedin School of Medicine, University of Otago, Dunedin, New Zealand.,Department of General Surgery, Christchurch Hospital, Christchurch, New Zealand
| | - G P Herbison
- Department of Preventive and Social Medicine, Dunedin School of Medicine, University of Otago, Dunedin, New Zealand
| | - S H Grainger
- Department of Surgical Sciences, Dunedin School of Medicine, University of Otago, Dunedin, New Zealand
| | - C H Khoo
- Department of Surgical Sciences, Dunedin School of Medicine, University of Otago, Dunedin, New Zealand
| | - M D Smith
- Department of Surgical Sciences, Dunedin School of Medicine, University of Otago, Dunedin, New Zealand.,Department of General Surgery, Dunedin Hospital, Dunedin, New Zealand
| | - J L McCall
- Department of Surgical Sciences, Dunedin School of Medicine, University of Otago, Dunedin, New Zealand.,Department of General Surgery, Dunedin Hospital, Dunedin, New Zealand.,Department of Surgery, School of Medicine, University of Auckland, Auckland, New Zealand.,New Zealand Liver Transplant Unit, Auckland, New Zealand
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Surgical Quality Assurance in COLOR III: Standardization and Competency Assessment in a Randomized Controlled Trial. Ann Surg 2020; 270:768-774. [PMID: 31573984 DOI: 10.1097/sla.0000000000003537] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
OBJECTIVE The aim of this study was to develop an objective and reliable surgical quality assurance system (SQA) for COLOR III, an international multicenter randomized controlled trial (RCT) comparing transanal total mesorectal excision (TaTME) with laparoscopic approach for rectal cancer. BACKGROUND OF SUMMARY DATA SQA influences outcome measures in RCTs such as lymph nodes harvest, in-hospital mortality, and locoregional cancer recurrence. However, levels of SQA are variable. METHOD Hierarchical task analysis of TaTME was performed. A 4-round Delphi methodology was applied for standardization of TaTME steps. Semistructured interviews were conducted in round 1 to identify key steps and tasks, which were rated as mandatory, optional, or prohibited in rounds 2 to 4 using questionnaires. Competency assessment tool (CAT) was developed and its content validity was examined by expert surgeons. Twenty unedited videos were assessed to test reliability using generalizability theory. RESULTS Eighty-three of 101 surgical tasks identified reached 70% agreement (26 mandatory, 56 optional, and 1 prohibited). An operative guide of standardized TaTME was created. CAT is matrix of 9 steps and 4 performance qualities: exposure, execution, adverse event, and end-product. The overall G-coefficient was 0.883. Inter-rater and interitem reliability were 0.883 and 0.986. To enter COLOR III, 2 unedited TaTME and 1 laparoscopic TME videos were submitted and assessed by 2 independent assessors using CAT. CONCLUSION We described an iterative approach to develop an objective SQA within multicenter RCT. This approach provided standardization, the development of reliable and valid CAT, and the criteria for trial entry and monitoring surgical performance during the trial.
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Lord AC, Hicks G, Pearce B, Tanno L, Pucher P. Safety and outcomes of laparoscopic cholecystectomy in the extremely elderly: a systematic review and meta-analysis. Acta Chir Belg 2019; 119:349-356. [PMID: 31437407 DOI: 10.1080/00015458.2019.1658356] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Background: Gallstones are a common cause of morbidity in the elderly. Operative treatment is often avoided due to concerns about poor outcomes but the evidence for this is unclear. We aim to consolidate available evidence assessing laparoscopic cholecystectomy outcomes in the extreme elderly (>80s) compared to younger patients. Methods: Studies comparing laparoscopic cholecystectomy in >80s with younger patients were considered. Total complications, mortality, conversion, bile duct injury, and length of stay were compared between the two groups. Results: Twelve studies including 366,522 patients were included. They were of moderate overall quality. The elderly group had more complicated gallbladder disease and also had more co-morbidities and a higher ASA grade. The risk of morbidity was lower in the younger group (RR 0.58 (95% CI 0.58-0.59)) with a slightly lower risk of conversion (RR 0.96 (0.94-0.98)) Length of stay was significantly longer for the elderly patients. Differences in mortality and bile duct injury were non-significant in all but one study. Conclusion: Laparoscopic cholecystectomy is safe and effective in the extreme elderly. Higher complication rates are predominantly related to increased co-morbidities and more complex gallbladder disease. Patients should be carefully selected, and cholecystectomy performed at an earlier stage to minimize these problems.
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Affiliation(s)
- Amy C. Lord
- Department of General Surgery, Croydon University Hospital, London, UK
| | - Georgina Hicks
- Department of General Surgery, Croydon University Hospital, London, UK
| | - Belinda Pearce
- Department of General Surgery, Royal Hampshire Hospital, Winchester, UK
| | - Lulu Tanno
- Department of General Surgery, University Hospital Southampton, Southampton, UK
| | - P.H. Pucher
- Department of Surgery, Portsmouth Hospitals NHS Trust, Portsmouth, UK
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Corrigan N, Marshall H, Croft J, Copeland J, Jayne D, Brown J. Exploring and adjusting for potential learning effects in ROLARR: a randomised controlled trial comparing robotic-assisted vs. standard laparoscopic surgery for rectal cancer resection. Trials 2018; 19:339. [PMID: 29945673 PMCID: PMC6020359 DOI: 10.1186/s13063-018-2726-0] [Citation(s) in RCA: 66] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2018] [Accepted: 06/07/2018] [Indexed: 01/27/2023] Open
Abstract
Background Commonly in surgical randomised controlled trials (RCT) the experimental treatment is a relatively new technique which the surgeons may still be learning, while the control is a well-established standard. This can lead to biased comparisons between treatments. In this paper we discuss the implementation of approaches for addressing this issue in the ROLARR trial, and points of consideration for future surgical trials. Methods ROLARR was an international, randomised, parallel-group trial comparing robotic vs. laparoscopic surgery for the curative treatment of rectal cancer. The primary endpoint was conversion to open surgery (binary). A surgeon inclusion criterion mandating a minimum level of experience in each technique was incorporated. Additionally, surgeon self-reported data were collected periodically throughout the trial to capture the level of experience of every participating surgeon. Multi-level logistic regression adjusting for operating surgeon as a random effect is used to estimate the odds ratio for conversion to open surgery between the treatment groups. We present and contrast the results from the primary analysis, which did not account for learning effects, and a sensitivity analysis which did. Results The primary analysis yields an estimated odds ratio (robotic/laparoscopic) of 0.614 (95% CI 0.311, 1.211; p = 0.16), providing insufficient evidence to conclude superiority of robotic surgery compared to laparoscopic in terms of the risk of conversion to open. The sensitivity analysis reveals that while participating surgeons in ROLARR were expert at laparoscopic surgery, some, if not all, were still learning robotic surgery. The treatment-effect odds ratio decreases by a factor of 0.341 (95% CI 0.121, 0.960; p = 0.042) per unit increase in log-number of previous robotic operations performed by the operating surgeon. The odds ratio for a patient whose operating surgeon has the mean experience level in ROLARR – 152.46 previous laparoscopic, 67.93 previous robotic operations – is 0.40 (95% CI 0.168, 0.953; p = 0.039). Conclusions In this paper we have demonstrated the implementation of approaches for accounting for learning in a practical example of a surgery RCT analysis. The results demonstrate the value of implementing such approaches, since we have shown that without them the ROLARR analysis would indeed have been confounded by the learning effects. Trial registration International Standard Randomised Controlled Trial Number (ISRCTN) registry, ID: ISRCTN80500123. Registered on 27 May 2010.
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Affiliation(s)
- Neil Corrigan
- Clinical Trials Research Unit, Leeds Institute of Clinical Trials Research, University of Leeds, Leeds, LS2 9JT, UK.
| | - Helen Marshall
- Clinical Trials Research Unit, Leeds Institute of Clinical Trials Research, University of Leeds, Leeds, LS2 9JT, UK
| | - Julie Croft
- Clinical Trials Research Unit, Leeds Institute of Clinical Trials Research, University of Leeds, Leeds, LS2 9JT, UK
| | - Joanne Copeland
- Clinical Trials Research Unit, Leeds Institute of Clinical Trials Research, University of Leeds, Leeds, LS2 9JT, UK
| | - David Jayne
- Department of Academic Surgery, Leeds Institute of Biological and Clinical Sciences, Clinical Sciences Building, University of Leeds, St. James's University Hospital, Leeds, LS9 7TF, UK
| | - Julia Brown
- Clinical Trials Research Unit, Leeds Institute of Clinical Trials Research, University of Leeds, Leeds, LS2 9JT, UK
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Valsamis EM, Golubic R, Glover TE, Husband H, Hussain A, Jenabzadeh AR. Modeling Learning in Surgical Practice. JOURNAL OF SURGICAL EDUCATION 2018; 75:78-87. [PMID: 28673804 DOI: 10.1016/j.jsurg.2017.06.015] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2017] [Accepted: 06/13/2017] [Indexed: 06/07/2023]
Abstract
OBJECTIVE Methods that model surgical learning curves are frequently descriptive and lack the mathematical rigor required to extract robust, meaningful, and quantitative information. We aimed to formulate a method to model learning that is tailored to dealing with the high variability seen in surgical data and can readily extract important quantitative information such as learning rate, length of learning, and learnt level of performance. METHODS We developed a method where progressively more complex models are fitted to learning data. These include novel models that split the learning data into 2 linear phases and fit adjoining lines using least squares regression. The models were compared and the least complex model was selected unless a more complex one was significantly better. Significance was tested by Fischer tests. We applied this method to total hip and knee replacements using imageless navigation, analyzing the operative time for a surgeon's first 50 and 60 operations, respectively. This method was then tested against 4 sets of simulated learning data. RESULTS The proposed method of progressive model complexity successfully modeled the learning curve among real operative data. It was also effective in deducing the underlying trends in simulated scenarios, created to represent typical situations that can practically arise in any learning process. CONCLUSIONS The novel modeling method can be used to extract meaningful and quantitative information from learning data displaying high variability seen in surgical practice. By using simple and intuitive models, the method is accessible to researchers and educators without the need for specialist statistical knowledge.
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Affiliation(s)
| | - Rajna Golubic
- Cardiology Department, Papworth Hospital, Papworth Everard, Cambridge, United Kingdom
| | | | - Henry Husband
- Faculty of Mathematics, University of Cambridge, Cambridge, United Kingdom
| | - Adnan Hussain
- Trauma and Orthopedics Department, Hinchingbrooke Hospital, Huntingdon, United Kingdom
| | - Amir-Reza Jenabzadeh
- Trauma and Orthopedics Department, Hinchingbrooke Hospital, Huntingdon, United Kingdom
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Learning Curve of a Minimally Invasive Technique for Transcrestal Sinus Floor Elevation: A Split-Group Analysis in a Prospective Case Series With Multiple Clinicians. IMPLANT DENT 2017; 24:517-26. [PMID: 26035375 DOI: 10.1097/id.0000000000000270] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
AIMS To assess the learning curve of a minimally invasive procedure for maxillary sinus floor elevation with a transcrestal approach (tSFE) and evaluate the influence of clinician's experience in implant surgery on its outcomes. MATERIALS AND METHODS Patients were treated by clinicians with different levels of experience in implant surgery and inexperienced with respect to the investigated tSFE technique. The initial (n = 13) and final (n = 13) groups treated by the expert clinician were compared for tSFE outcomes. Additionally, the high, moderate, and low groups (n = 20 each) treated by the expert, moderately experienced, and low experienced clinician, respectively, were compared. RESULTS (1) No significant differences in clinical and radiographic outcomes were observed between initial and final groups; (2) high, moderate, and low groups showed substantial vertical augmentation in limited operation time with treatment outcomes being influenced by the level of experience in implant surgery. CONCLUSIONS The investigated technique allows for a substantial vertical augmentation at limited operation times when used by different clinicians. The extent of sinus lift (as radiographically assessed) seems to be influenced by the clinician's level of experience in implant dentistry.
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Potter S, Conroy EJ, Williamson PR, Thrush S, Whisker LJ, Skillman JM, Barnes NLP, Cutress RI, Teasdale EM, Mills N, Mylvaganam S, Branford OA, McEvoy K, Jain A, Gardiner MD, Blazeby JM, Holcombe C. The iBRA (implant breast reconstruction evaluation) study: protocol for a prospective multi-centre cohort study to inform the feasibility, design and conduct of a pragmatic randomised clinical trial comparing new techniques of implant-based breast reconstruction. Pilot Feasibility Stud 2016; 2:41. [PMID: 27965859 PMCID: PMC5154059 DOI: 10.1186/s40814-016-0085-8] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2016] [Accepted: 06/10/2016] [Indexed: 11/30/2022] Open
Abstract
BACKGROUND Implant-based breast reconstruction (IBBR) is the most commonly performed reconstructive procedure in the UK. The introduction of techniques to augment the subpectoral pocket has revolutionised the procedure, but there is a lack of high-quality outcome data to describe the safety or effectiveness of these techniques. Randomised controlled trials (RCTs) are the best way of comparing treatments, but surgical RCTs are challenging. The iBRA (implant breast reconstruction evaluation) study aims to determine the feasibility, design and conduct of a pragmatic RCT to examine the effectiveness of approaches to IBBR. METHODS/DESIGN The iBRA study is a trainee-led research collaborative project with four phases:Phase 1 - a national practice questionnaire (NPQ) to survey current practicePhase 2 - a multi-centre prospective cohort study of patients undergoing IBBR to evaluate the clinical and patient-reported outcomesPhase 3- an IBBR-RCT acceptability survey and qualitative work to explore patients' and surgeons' views of proposed trial designs and candidate outcomes.Phase 4 - phases 1 to 3 will inform the design and conduct of the future RCT All centres offering IBBR will be encouraged to participate by the breast and plastic surgical professional associations (Association of Breast Surgery and British Association of Plastic Reconstructive and Aesthetic Surgeons). Data collected will inform the feasibility of undertaking an RCT by defining current practice and exploring issues surrounding recruitment, selection of comparator arms, choice of primary outcome, sample size, selection criteria, trial conduct, methods of data collection and feasibility of using the trainee collaborative model to recruit patients and collect data. DISCUSSION The preliminary work undertaken within the iBRA study will determine the feasibility, design and conduct of a definitive RCT in IBBR. It will work with the trainee collaborative to build capacity by creating an infrastructure of research-active breast and plastic surgeons which will facilitate future high-quality research that will ultimately improve outcomes for all women seeking reconstructive surgery. TRIAL REGISTRATION ISRCTN37664281.
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Affiliation(s)
- Shelley Potter
- Bristol Centre for Surgical Research, School of Social and Community Medicine, University of Bristol, Room 3.12 Canynge Hall, 39 Whatley Road, Bristol, BS8 2PS UK
| | - Elizabeth J. Conroy
- MRC North West Hub for Trials Methodology Research, Department of Biostatistics, Clinical Trials Research Centre, University of Liverpool, Liverpool, L69 3GS UK
| | - Paula R. Williamson
- MRC North West Hub for Trials Methodology Research, Department of Biostatistics, Clinical Trials Research Centre, University of Liverpool, Liverpool, L69 3GS UK
| | - Steven Thrush
- Breast Unit, Worcester Royal Hospital. Charles Hastings Way, Worcester, WR5 1DD UK
| | - Lisa J. Whisker
- Breast Institute, Nottingham University Hospitals NHS Trust, Hucknall Road, Nottingham, NG5 1PB UK
| | - Joanna M Skillman
- Department of Plastic Surgery, University Hospitals Coventry and Warwickshire NHS Trust, Clifford Bridge Road, Coventry, CV2 2DX UK
| | - Nicola L. P. Barnes
- The Nightingale Centre Breast Unit, University Hospital of South Manchester NHS Foundation Trust, Southmoor Road, Manchester, M23 9LT UK
| | - Ramsey I. Cutress
- Breast Unit, University Hospital Southampton, Tremona Road, Southampton, Hampshire SO16 6YD UK
- Faculty of Medicine, University of Southampton, University Road, Southampton, SO17 1BJ UK
| | - Elizabeth M. Teasdale
- Linda McCartney Centre, Royal Liverpool and Broadgreen University Hospital, Prescot Street, Liverpool, L7 8XP UK
| | - Nicola Mills
- Bristol Centre for Surgical Research, School of Social and Community Medicine, University of Bristol, Room 3.12 Canynge Hall, 39 Whatley Road, Bristol, BS8 2PS UK
| | - Senthurun Mylvaganam
- New Cross Hospital, Royal Wolverhampton Hospitals NHS Trust, Wednesfield Way, Wolverhampton, WV10 0QP UK
| | - Olivier A. Branford
- Department of Plastic Surgery, The Royal Marsden NHS Foundation Trust, Fulham Road, London, SW3 6JJ UK
| | | | - Abhilash Jain
- Imperial College London NHS Trust, London, SW7 2AZ UK
- Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, University of Oxford, Nuffield Orthopaedic Centre, Windmill Road, Headington, Oxford OX3 7HE UK
| | - Matthew D. Gardiner
- Imperial College London NHS Trust, London, SW7 2AZ UK
- Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, University of Oxford, Nuffield Orthopaedic Centre, Windmill Road, Headington, Oxford OX3 7HE UK
| | - Jane M. Blazeby
- Bristol Centre for Surgical Research, School of Social and Community Medicine, University of Bristol, Room 3.12 Canynge Hall, 39 Whatley Road, Bristol, BS8 2PS UK
| | - Christopher Holcombe
- Linda McCartney Centre, Royal Liverpool and Broadgreen University Hospital, Prescot Street, Liverpool, L7 8XP UK
| | - on behalf of the Breast Reconstruction Research Collaborative
- Bristol Centre for Surgical Research, School of Social and Community Medicine, University of Bristol, Room 3.12 Canynge Hall, 39 Whatley Road, Bristol, BS8 2PS UK
- MRC North West Hub for Trials Methodology Research, Department of Biostatistics, Clinical Trials Research Centre, University of Liverpool, Liverpool, L69 3GS UK
- Breast Unit, Worcester Royal Hospital. Charles Hastings Way, Worcester, WR5 1DD UK
- Breast Institute, Nottingham University Hospitals NHS Trust, Hucknall Road, Nottingham, NG5 1PB UK
- Department of Plastic Surgery, University Hospitals Coventry and Warwickshire NHS Trust, Clifford Bridge Road, Coventry, CV2 2DX UK
- The Nightingale Centre Breast Unit, University Hospital of South Manchester NHS Foundation Trust, Southmoor Road, Manchester, M23 9LT UK
- Breast Unit, University Hospital Southampton, Tremona Road, Southampton, Hampshire SO16 6YD UK
- Faculty of Medicine, University of Southampton, University Road, Southampton, SO17 1BJ UK
- Linda McCartney Centre, Royal Liverpool and Broadgreen University Hospital, Prescot Street, Liverpool, L7 8XP UK
- New Cross Hospital, Royal Wolverhampton Hospitals NHS Trust, Wednesfield Way, Wolverhampton, WV10 0QP UK
- Department of Plastic Surgery, The Royal Marsden NHS Foundation Trust, Fulham Road, London, SW3 6JJ UK
- City Hospital, Dudley Road, West Midlands, B18 7QH UK
- Imperial College London NHS Trust, London, SW7 2AZ UK
- Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, University of Oxford, Nuffield Orthopaedic Centre, Windmill Road, Headington, Oxford OX3 7HE UK
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Papachristofi O, Jenkins D, Sharples LD. Assessment of learning curves in complex surgical interventions: a consecutive case-series study. Trials 2016; 17:266. [PMID: 27245050 PMCID: PMC4888720 DOI: 10.1186/s13063-016-1383-4] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2015] [Accepted: 05/05/2016] [Indexed: 11/26/2022] Open
Abstract
Background Surgical interventions are complex, which complicates their rigorous assessment through randomised clinical trials. An important component of complexity relates to surgeon experience and the rate at which the required level of skill is achieved, known as the learning curve. There is considerable evidence that operator performance for surgical innovations will change with increasing experience. Such learning effects complicate evaluations; the start of the trial might be delayed, resulting in loss of surgeon equipoise or, if an assessment is undertaken before performance has stabilised, the true impact of the intervention may be distorted. Methods Formal estimation of learning parameters is necessary to characterise the learning curve, model its evolution and adjust for its presence during assessment. Current methods are either descriptive or model the learning curve through three main features: the initial skill level, the learning rate and the final skill level achieved. We introduce a fourth characterising feature, the duration of the learning period, which provides an estimate of the point at which learning has stabilised. We propose a two-phase model to estimate formally all four learning curve features. Results We demonstrate that the two-phase model can be used to estimate the end of the learning period by incorporating a parameter for estimating the duration of learning. This is achieved by breaking down the model into a phase describing the learning period and one describing cases after the final skill level is reached, with the break point representing the length of learning. We illustrate the method using cardiac surgery data. Conclusions This modelling extension is useful as it provides a measure of the potential cost of learning an intervention and enables statisticians to accommodate cases undertaken during the learning phase and assess the intervention after the optimal skill level is reached. The limitations of the method and implications for the optimal timing of a definitive randomised controlled trial are also discussed. Electronic supplementary material The online version of this article (doi:10.1186/s13063-016-1383-4) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Olympia Papachristofi
- MRC Biostatistics Unit, Robinson Way, CB4 3EU, Cambridge, UK. .,Comprehensive Health Research Division, Leeds Institute of Clinical Trials Research, University of Leeds, 71-75 Clarendon Road, LS2 9PH, Leeds, UK.
| | - David Jenkins
- Departments of Surgery, Anaesthesia and Clinical Audit, Papworth Hospital, CB23 8RE,, Cambridge, UK
| | - Linda D Sharples
- Comprehensive Health Research Division, Leeds Institute of Clinical Trials Research, University of Leeds, 71-75 Clarendon Road, LS2 9PH, Leeds, UK
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Potter S, Mills N, Cawthorn SJ, Donovan J, Blazeby JM. Time to be BRAVE: is educating surgeons the key to unlocking the potential of randomised clinical trials in surgery? A qualitative study. Trials 2014; 15:80. [PMID: 24628821 PMCID: PMC4003809 DOI: 10.1186/1745-6215-15-80] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2013] [Accepted: 02/26/2014] [Indexed: 01/11/2023] Open
Abstract
BACKGROUND Well-designed randomised clinical trials (RCTs) provide the best evidence to inform decision-making and should be the default option for evaluating surgical procedures. Such trials can be challenging, and surgeons' preferences may influence whether trials are initiated and successfully conducted and their results accepted. Preferences are particularly problematic when surgeons' views play a key role in procedure selection and patient eligibility. The bases of such preferences have rarely been explored. Our aim in this qualitative study was to investigate surgeons' preferences regarding the feasibility of surgical RCTs and their understanding of study design issues using breast reconstruction surgery as a case study. METHODS Semistructured qualitative interviews were undertaken with a purposive sample of 35 professionals practicing at 15 centres across the United Kingdom. Interviews were transcribed verbatim and analysed thematically using constant comparative techniques. Sampling, data collection and analysis were conducted concurrently and iteratively until data saturation was achieved. RESULTS Surgeons often struggle with the concept of equipoise. We found that if surgeons did not feel 'in equipoise', they did not accept randomisation as a method of treatment allocation. The underlying reasons for limited equipoise were limited appreciation of the methodological weaknesses of data derived from nonrandomised studies and little understanding of pragmatic trial design. Their belief in the value of RCTs for generating high-quality data to change or inform practice was not widely held. CONCLUSION There is a need to help surgeons understand evidence, equipoise and bias. Current National Institute of Health Research/Medical Research Council investment into education and infrastructure for RCTs, combined with strong leadership, may begin to address these issues or more specific interventions may be required.
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Affiliation(s)
- Shelley Potter
- Bristol Centre for Surgical Research, School of Social and Community Medicine, University of Bristol, Canynge Hall, 39 Whatley Road, Bristol BS8 2PS, UK
- Division of Surgery, Head and Neck, University Hospitals Bristol NHS Foundation Trust, Upper Maudlin Street, Bristol BS2 8HW, UK
| | - Nicola Mills
- Bristol Centre for Surgical Research, School of Social and Community Medicine, University of Bristol, Canynge Hall, 39 Whatley Road, Bristol BS8 2PS, UK
| | - Simon J Cawthorn
- Bristol Breast Care Centre, North Bristol NHS Trust, Southmead Hospital, Bristol BS10 5NB, UK
| | - Jenny Donovan
- Bristol Centre for Surgical Research, School of Social and Community Medicine, University of Bristol, Canynge Hall, 39 Whatley Road, Bristol BS8 2PS, UK
| | - Jane M Blazeby
- Bristol Centre for Surgical Research, School of Social and Community Medicine, University of Bristol, Canynge Hall, 39 Whatley Road, Bristol BS8 2PS, UK
- Division of Surgery, Head and Neck, University Hospitals Bristol NHS Foundation Trust, Upper Maudlin Street, Bristol BS2 8HW, UK
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Trombelli L, Franceschetti G, Stacchi C, Minenna L, Riccardi O, Di Raimondo R, Rizzi A, Farina R. Minimally invasive transcrestal sinus floor elevation with deproteinized bovine bone or β-tricalcium phosphate: a multicenter, double-blind, randomized, controlled clinical trial. J Clin Periodontol 2014; 41:311-9. [DOI: 10.1111/jcpe.12210] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/28/2013] [Indexed: 11/28/2022]
Affiliation(s)
- Leonardo Trombelli
- Research Centre for the Study of Periodontal and Peri-Implant Diseases; University of Ferrara; Ferrara Italy
| | - Giovanni Franceschetti
- Research Centre for the Study of Periodontal and Peri-Implant Diseases; University of Ferrara; Ferrara Italy
| | | | - Luigi Minenna
- Research Centre for the Study of Periodontal and Peri-Implant Diseases; University of Ferrara; Ferrara Italy
| | | | | | - Alessandro Rizzi
- Research Centre for the Study of Periodontal and Peri-Implant Diseases; University of Ferrara; Ferrara Italy
| | - Roberto Farina
- Research Centre for the Study of Periodontal and Peri-Implant Diseases; University of Ferrara; Ferrara Italy
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Factors influencing women's decision to participate or not in a surgical randomised controlled trial for surgical treatment of female stress urinary incontinence. BIOMED RESEARCH INTERNATIONAL 2013; 2013:139813. [PMID: 24151581 PMCID: PMC3789309 DOI: 10.1155/2013/139813] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/29/2013] [Accepted: 07/29/2013] [Indexed: 11/21/2022]
Abstract
The study aims to explore the potentially influential factors affecting women's decision to accept/decline participation in surgical randomised trial using a novel acceptance/refusal questionnaire (ARQ). All women who were eligible to participate in SIMS-RCT were asked to complete the relevant section (acceptance/refusal) of the ARQ. Women reported its degree of relevance for their decision on a six-point Likert scale (0 = highly irrelevant, 5 = highly relevant). 135 (98%) and 31 (70%) women completed the acceptance and refusal sections of the ARQ, respectively. The most influencing factor in women's acceptance was the anticipation of “potential personal benefit”; percentage of relevance (POR) was 91.9%, followed by interest in helping others by “supporting innovative medical research”; POR was 87.7%. Most influencing factor in refusal for participation was “do not have time for follow-up”; POR was 56.8%, followed by “do not like the concept of randomisation”; POR was 54.4%. In conclusion, this study identifies the most influential factors relevant to women decision-making whether or not to participate in RCTs assessing surgical interventions for female stress urinary incontinence (SUI). A number of factors leading to refusal of participation are potentially correctable leading to better recruitment rates in future RCTs.
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Sgourakis G, Lanitis S, Karaliotas C, Gockel I, Kaths M, Karaliotas C. [Laparoscopic versus endoscopic primary management of choledocholithiasis. A retrospective case-control study]. Chirurg 2013; 83:897-903. [PMID: 22476872 DOI: 10.1007/s00104-012-2279-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
BACKGROUND The aim was to present the long-term results of one-stage laparoscopic procedure for the management of common bile duct (CBD) lithiasis in comparison with the primary endoscopic approach via ERCP. PATIENTS AND METHODS A retrospective case-control study was performed to determine the outcome of patients treated for CBD lithiasis (04/1997 - 11/2011). Data of patients with choledocholithiasis undergoing the two treatment modalities - laparoscopic common bile duct exploration plus laparoscopic cholecystectomy (LCBDE + LC, group A, n = 101) versus endoscopic retrograde cholangiopancreatography/sphincterotomy and laparoscopic cholecystectomy (ERCP/S + LC, group B, n = 116) were matched according to their clinical characteristics. Patients of group A underwent either laparoscopic choledochotomy or transcystic exploration. The policy was to convert to open choledochotomy only after the sequential application of the two treatment modalities (laparoscopic/endoscopic procedure) had failed. RESULTS No significant difference in morbidity was found between the groups (group A 8% versus group B 11.2%). Conversion to another procedure was mandatory in 12 out of 101 and 17 out of 116 patients of groups A and B, respectively. The mean follow-up period was 7.8 years (range 1-12 years). Effective laparoscopic treatment of CBD stones (cholecystectomy and CBD clearance) was possible in 89 of the 101 patients in group A (88.1%) compared with 99 of the 116 patients in group B (85.4%) after the endoscopic approach. CONCLUSIONS This study showes that both - primary endoscopy and one-stage laparoscopic management of CBD lithiasis - are highly effective and safe with comparable results.
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Affiliation(s)
- G Sgourakis
- 2nd Surgical Department and Surgical Oncology Unit of Korgialenio - Benakio, Red Cross Hospital Athens, Athens, Greece
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Diener MK, Simon T, Büchler MW, Seiler CM. Surgical evaluation and knowledge transfer--methods of clinical research in surgery. Langenbecks Arch Surg 2011; 397:1193-9. [PMID: 21424797 DOI: 10.1007/s00423-011-0775-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2011] [Accepted: 03/02/2011] [Indexed: 01/04/2023]
Abstract
PURPOSE This article aims to outline the framework of surgical evaluation and knowledge transfer. Therefore, special design issues affecting surgical clinical research will be discussed. Moreover, principles and challenges of knowledge transfer from research into practice will be addressed. BACKGROUND The ultimate goal of academic surgery is to improve surgical and perioperative care in order to achieve the best outcomes for patients. Randomized controlled trials and reviews with and without meta-analyses are fundamental requirements for evidence-based decision making. DISCUSSION Despite calls for more rigorous research methods in surgery, the frequency of high-quality randomized controlled trials and systematic reviews is low. Specific methodological and design issues have to be implemented for valid evaluation of surgical procedures. Thus, general catchwords of clinical epidemiology such as timing, randomization, registration, and reporting standards demand special appraisal. Moreover, blinding methods, placebo controls, learning curves, standardized outcome assessment, and generalizability are critical design issues in surgical trials. Moreover, systematic reviews and meta-analyses are desirable for answering clinical issues or defining new research questions. CONCLUSION For a rigorous evaluation of surgical procedures, a basic understanding of research methodology is urgently needed, and to improve methodological expertise, collaboration between surgeons and methodologists is encouraged.
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Affiliation(s)
- Markus K Diener
- Department of General, Visceral and Transplantation Surgery, University of Heidelberg, Im Neuenheimer Feld 110, 69120, Heidelberg, Germany.
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Levels of Evidence for Laparoscopic Surgery for Colorectal Cancer. J Am Coll Surg 2011; 212:269-70; author reply 270-1. [DOI: 10.1016/j.jamcollsurg.2010.10.010] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2010] [Accepted: 10/21/2010] [Indexed: 12/20/2022]
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Moon NR, Min SK, Lee HK. Comparison of Long-term Follow-up Results of Open Common Bile Duct Exploration and Laparoscopic Common Bile Duct Exploration in Common Bile Duct Stone Disease. JOURNAL OF THE KOREAN SURGICAL SOCIETY 2010. [DOI: 10.4174/jkss.2010.79.1.58] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Na Ra Moon
- Department of Surgery, School of Medicine, Ewha Womans University, Seoul, Korea
| | - Seog Ki Min
- Department of Surgery, School of Medicine, Ewha Womans University, Seoul, Korea
| | - Hyeon Kook Lee
- Department of Surgery, School of Medicine, Ewha Womans University, Seoul, Korea
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Cholecystocholedocholithiasis: a case-control study comparing the short- and long-term outcomes for a "laparoscopy-first" attitude with the outcome for sequential treatment (systematic endoscopic sphincterotomy followed by laparoscopic cholecystectomy). Surg Endosc 2009; 24:51-62. [PMID: 19466493 DOI: 10.1007/s00464-009-0511-6] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2008] [Revised: 04/04/2009] [Accepted: 04/20/2009] [Indexed: 02/06/2023]
Abstract
BACKGROUND No unanimous consensus has been achieved regarding the ideal management of cholecystocholedocholithiasis. The treatment of gallbladder and common bile duct (CBD) stones may be achieved currently according to a two-step-protocol (endoscopic sphincterotomy associated with laparoscopic cholecystectomy) or by a one-step laparoscopic procedure, including exploration of the CBD and cholecystectomy. Endoscopic sphincterotomy is reported to have considerable morbidity/mortality and CBD stone recurrence rates, whereas laparoscopic CBD clearance is a demanding procedure, which to date has not spread beyond specialized environments. METHODS To evaluate our "laparoscopy first" (LF) approach for patients affected by gallbladder/CBD stones (laparoscopic exploration and intraoperative decision whether to proceed with laparoscopic CBD exploration or to postpone CBD stone treatment to a postoperative endoscopic retrograde cholangiopancreatography [ERCP]), we performed a retrospective, two-center case-control comparison of the postoperative outcome for 49 consecutive patients treated for gallbladder/CBD stones from January 2000 through December 2004. The results obtained with this LF approach were compared with those achieved with the traditional, "endoscopy-first" (EF) approach (ERCP plus endoscopic sphincterotomy, followed by laparoscopic cholecystectomy). The mean follow-up period was 6.4 years (range, 4-8 years). RESULTS No difference emerged concerning early and late complications, mortality, or laparotomies needed to accomplish cholecystectomy and CBD clearance. The postoperative hospital stay was shorter for the LF group. In the LF group, only 22 patients underwent choledochotomy (45%), and 15 patients underwent perioperative ERCP (30%). Conversions decreased with practice. After choledochotomy, an increasing number of patients underwent primary closure of the CBD (with no biliary drain), without complications. CONCLUSIONS An LF approach to gallbladder/CBD stones is safe and feasible. It may allow the majority of surgeons to avoid excessively difficult/dangerous surgical procedures as well as unnecessary ERCPs in most cases. A tendency toward a lower incidence of conversions and a rarer use of biliary drains may lead to an improved immediate outcome for patients undergoing an LF approach.
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Cook JA. The challenges faced in the design, conduct and analysis of surgical randomised controlled trials. Trials 2009; 10:9. [PMID: 19200379 PMCID: PMC2654883 DOI: 10.1186/1745-6215-10-9] [Citation(s) in RCA: 221] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2008] [Accepted: 02/06/2009] [Indexed: 12/15/2022] Open
Abstract
Randomised evaluations of surgical interventions are rare; some interventions have been widely adopted without rigorous evaluation. Unlike other medical areas, the randomised controlled trial (RCT) design has not become the default study design for the evaluation of surgical interventions. Surgical trials are difficult to successfully undertake and pose particular practical and methodological challenges. However, RCTs have played a role in the assessment of surgical innovations and there is scope and need for greater use. This article will consider the design, conduct and analysis of an RCT of a surgical intervention. The issues will be reviewed under three headings: the timing of the evaluation, defining the research question and trial design issues. Recommendations on the conduct of future surgical RCTs are made. Collaboration between research and surgical communities is needed to address the distinct issues raised by the assessment of surgical interventions and enable the conduct of appropriate and well-designed trials.
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Affiliation(s)
- Jonathan A Cook
- Health Services Research Unit, University Of Aberdeen, Health Sciences Building, Foresterhill, Aberdeen, Scotland, AB25 2ZD, UK.
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Blümle A, Antes G, Diener MK. [Hand searching for controlled clinical trials in German surgical journals. A contribution to evidence-based surgery]. Chirurg 2008; 78:1052-7. [PMID: 17622501 DOI: 10.1007/s00104-007-1372-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
BACKGROUND The identification of all available and relevant study reports is mandatory for a comprehensive assessment of randomised (RCTs) and controlled clinical trials (CCTs) in systematic reviews. Incomplete compilation of health care journals in electronic databases and incorrect indexing of the studies impair the result of a systematic literature search. An additional search in medical journals that are not listed in electronic databases can obtain higher search precision. METHODS In the hand searching project of the Cochrane Collaboration, in Germany 14 surgical journals were searched manually for RCTs and CCTs. The identified study reports were compared with Medline records, and the publication frequency was analysed. The study reports were published in the Cochrane Library and are henceforth available for inclusion in systematic reviews. RESULTS Four hundred (77%) of the 519 published volumes in the 14 surgical journals were searched for RCTs and CCTs. Of the 1152 controlled trials (670 RCTs and 482 CCTs) identified, 674 (58%) were not included in Medline. CONCLUSIONS The gap between the number of hand search results and the number of Medline indexed RCTs and CCTs is also reflected in other special medical fields. To ensure completeness of the literature compilation, the hand searching project should be continued.
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Affiliation(s)
- A Blümle
- Deutsches Cochrane Zentrum, Abteilung für Medizinische Biometrie und Statistik, Institut für Medizinische Biometrie und Informatik, Universitätsklinikum, Stefan-Meier-Strasse 26, Freiburg, Germany.
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Boutron I, Ravaud P, Nizard R. The design and assessment of prospective randomised, controlled trials in orthopaedic surgery. ACTA ACUST UNITED AC 2007; 89:858-63. [PMID: 17673575 DOI: 10.1302/0301-620x.89b7.19440] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Randomised controlled trials represent the gold standard in the evaluation of outcome of treatment. They are needed because differences between treatment effects have been minimised and observational studies may give a biased estimation of the outcome. However, conducting this kind of trial is challenging. Several methodological issues, including patient or surgeon preference, blinding, surgical standardisation, as well as external validity, have to be addressed in order to lower the risk of bias. Specific tools have been developed in order to take into account the specificity of evaluation of the literature on non-pharmacological intervention. A better knowledge of methodological issues will allow the orthopaedic surgeon to conduct more appropriate studies and to better appraise the limits of his intervention.
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Affiliation(s)
- I Boutron
- Université Paris VII Denis Diderot, Paris, France
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22
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Gorst-Rasmussen A, Spiegelhalter DJ, Bull C. Monitoring the introduction of a surgical intervention with long-term consequences. Stat Med 2007; 26:512-31. [PMID: 16538698 DOI: 10.1002/sim.2548] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Surgical innovations are often introduced for their expected long-term benefits, but the decision to abandon the existing treatment must be based on the available short-term data and rational judgment. We present a framework for monitoring the introduction of a surgical intervention with long-term consequences and failure-time endpoints. The framework is based on Bayesian methods, and formally combines study data, clinical opinion, and external evidence to construct a posterior survival function from which intuitive summary statistics can be extracted to aid decision making. It incorporates learning effects and is adaptable to a wide variety of settings. The methods are illustrated on survival data from a cohort of 325 consecutive neonates treated for simple transposition of the great arteries with either the Senning or the Switch operation during the period 1978-1998.
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Abstract
Integrating health-related quality of life (HRQOL) as an endpoint for randomized surgical trials provides valuable insight into the patients' perspective on treatment outcome. Health related quality of life data also play a role in ensuring fully informed consent, determining treatment options and informing treatment decision making. However, few randomized surgical trials have been conducted that meet the minimum requirements for rigorous HRQL assessment and, despite increasing efforts to improve the reporting of randomized trials, many are still not adequately performed. Such methodologic limitations may influence trial findings for HRQL outcomes and undermine the ability of the data collected to inform clinical practice. This review describes key methodological aspects of HRQL assessment that are required in randomized trials to ensure that data are robust. This includes choice of HRQL instrument, the method and timing of assessments and data analysis and presentation. The review also makes recommendations for future research in this area.
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Affiliation(s)
- Kerry Avery
- Department of Social Medicine, University of Bristol, Bristol, United Kingdom
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Costi R, DiMauro D, Mazzeo A, Boselli AS, Contini S, Violi V, Roncoroni L, Sarli L. Routine laparoscopic cholecystectomy after endoscopic sphincterotomy for choledocholithiasis in octogenarians: is it worth the risk? Surg Endosc 2006; 21:41-7. [PMID: 17111279 DOI: 10.1007/s00464-006-0169-2] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2006] [Accepted: 05/11/2006] [Indexed: 02/06/2023]
Abstract
BACKGROUND No unanimous consensus has been reached as to the need for routine laparoscopic cholecystectomy (LC) after endoscopic sphincterotomy (ES) for choledocholithiasis in very elderly patients, who are considered as high-risk subjects for surgery. METHODS From 1991 through 1997, 170 patients were referred to undergo preoperative ES and routine LC for common bile duct (CBD) stones. The results for 27 patients (age 80 years or older) were compared with those achieved for younger patients. Successively, in a retrospective case-control study, the results for the selected patients were compared with those for 27 very elderly patients who underwent endoscopic retrograde cholangiopancreatography (ERCP), but did not receive LC. The mean follow-up period was 126 months. RESULTS Octogenarians showed longer surgery time (79 vs 51 min) and postoperative hospital stay (2.8 vs 1.2 days), as well as more early low-grade complications (15% vs 3%), whereas there were no differences in conversion rate or serious complications. Recurrent symptoms or complications developed in 48% of octogenarians not undergoing routine LC, and 30% finally needed surgery. One patient in the control group died after emergency cholecystectomy for acute cholecystitis. The results of surgery were significantly poorer for the control group. CONCLUSIONS Although a "wait-and-see" policy allowed two-thirds of LCs to be avoided in octogenarians, biliary-related events developed for every second patient, often requiring delayed surgery, with poorer results. Sequential treatment (ES followed by elective LC) is a safe procedure for octogenarians, and should be considered as a standard, definitive treatment for cholecystocholedocholithiasis even after the age of 80 years.
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Affiliation(s)
- R Costi
- Dipartimento di Scienze Chirurgiche, Università degli Studi di Parma, Via Gramsci 14, 43100, Parma, Italy.
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McCall JL, Sharples K, Jadallah F. Systematic review of randomized controlled trials comparing laparoscopic with open appendicectomy. Br J Surg 2005. [DOI: 10.1046/j.1365-2168.1997.02848.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Affiliation(s)
- Philip S Barie
- Department of Surgery, Weill Medical College of Cornell University, New York, NY 10021, USA.
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Boutron I, Tubach F, Giraudeau B, Ravaud P. Blinding was judged more difficult to achieve and maintain in nonpharmacologic than pharmacologic trials. J Clin Epidemiol 2004; 57:543-50. [PMID: 15246122 DOI: 10.1016/j.jclinepi.2003.12.010] [Citation(s) in RCA: 191] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/01/2003] [Indexed: 10/26/2022]
Abstract
OBJECTIVE To compare the feasibility of blinding and the perceived risk of unblinding in trials evaluating pharmacologic (PT) and nonpharmacologic treatments (NPT) of hip or knee osteoarthritis. STUDY DESIGN AND SETTING Two independent reviewers assessed the feasibility of blinding patients, care providers, and outcome assessors, the perceived risk of unblinding, and whether blinding was reported in 110 reports of randomized controlled trials (RCTs) evaluating PT and NPT in patients with hip or knee osteoarthritis. RESULTS Blinding was considered to be possible less often in NPT trials than in PT trials for patients (42 vs. 96%; P <.001), care providers (12 vs. 96%; P <.001), and outcome assessors (34 vs. 98%; P <.001). When blinding was judged feasible, the perceived risk of unblinding was more often considered moderate or important in NPT than PT trials for patients (35 vs. 14%, P=.02) and outcome assessors (44 vs. 10%, P=.0004). When blinding was judged feasible, it was reported less often in NPT reports than in PT reports for patients (46 vs. 98%, P <.001), care providers (43 vs. 83%, P=.03), and outcome assessors (72 vs. 98%, P=.0006). CONCLUSION Blinding appears to be more difficult to achieve and unblinding may occur more often in NPT than PT trials.
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Affiliation(s)
- Isabelle Boutron
- INSERM EMI 03 57, Département d'Epidémiologie, Biostatistique et Recherche Clinique, Groupe Hospitalier Bichat-Claude Bernard, Assistance Publique-Hôpitaux de Paris, Faculté Xavier Bichat, Université Paris 7, France.
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Costi R, Denet C, Sarli L, Perniceni T, Roncoroni L, Gayet B. Laparoscopy in the last decade of the millennium: have we really improved? Surg Endosc 2003; 17:791-7. [PMID: 12582758 DOI: 10.1007/s00464-002-9108-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2002] [Accepted: 09/12/2002] [Indexed: 10/26/2022]
Abstract
BACKGROUND The aims of the study were to evaluate the evolution of laparoscopic surgery during the past decade in terms of variations in the quality (complexity) of the procedures performed and of modifications in patient outcome. METHODS A retrospective analysis was performed of 3022 consecutive patients undergoing 99 different laparoscopic procedures at a center specialized in laparoscopic abdominal surgery. All the procedures were classified according to three classes of complexity. Results relating to the first 1511 patients were compared to those of the last 1511 patients. RESULTS In the second group, medium- to high-class complexity procedures significantly increased, conversion rate was higher only for straightforward procedures, duration of low- to medium-class complexity procedures decreased, only the rate of slight complications increased, and mean postoperative hospital stay was longer. Frequency of conversion in medium- to high-class complexity procedures and severe complications was not different in the two periods. CONCLUSIONS The quality of laparoscopic surgery has improved during the past decade, with no increase in the frequency of conversion or of major complications.
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Affiliation(s)
- R Costi
- Instituto di Clinica Chirurgica Generale e Terapia Chirurgica, Università di Parma, Via Gramsci 14, 43100 Parma, Italy.
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Pace KT, Honey RJD. Unique methodological issues facing randomized controlled trials of endourologic procedures. J Endourol 2002; 16:457-63. [PMID: 12396437 DOI: 10.1089/089277902760367403] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Randomized controlled trials provide the optimal design for evaluating the effectiveness of treatment but have not been widely accepted by surgical investigators. Although there are several methodological and ethical difficulties, none is insurmountable. In the United Kingdom, a regulatory agency has been established to supervise the introduction of new medical procedures, and something similar might be seen in the United States, particularly given the pressure from the government and third-party payors for proof of efficacy and cost effectiveness. Endourologists have responded to similar challenges in the past and must continue to do so.
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Affiliation(s)
- Kenneth T Pace
- Division of Urology, St. Michael's Hospital, University of Toronto, 61 Queen Street E, Suite 0193Q, Toronto, Ontario, Canada M5C 2T2.
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Henshaw R, Coyle C, Low S, Barry C. A retrospective cohort study comparing microwave endometrial ablation with levonorgestrel-releasing intrauterine device in the management of heavy menstrual bleeding. Aust N Z J Obstet Gynaecol 2002; 42:205-9. [PMID: 12069151 DOI: 10.1111/j.0004-8666.2002.00205.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
OBJECTIVE To compare microwave endometrial ablation (MEA) with a levonorgestrel-releasing intrauterine device (Mirena) in the management of heavy menstrual bleeding. DESIGN A retrospective cohort study SAMPLE Thirty-nine women were treated with MEA and 23 women with Mirena, in the South East Regional Health Service of South Australia during 1998 to 2001; the mean duration of follow-up was 14.6 months. MAIN OUTCOME MEASURES Primary measures included acceptability of the treatment process, effectiveness of the treatment, and satisfaction with outcomes. Secondary measures included side effects, complications and quality of life (using the SF-36). RESULTS Acceptability of the treatment process and satisfaction with outcomes was very high for both procedures. Each treatment led to a statistically significant reduction in menstrual bleeding (p < 0.0001) and dysmenorrhoea scores (p < 0.002). CONCLUSIONS There were no statistical differences between the two treatments for any of the primary or secondary outcome measures assessed. The treatments seem equally effective in the management of heavy menstrual loss.
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Affiliation(s)
- Richard Henshaw
- South East Regional Health Service, Adelaide, South Australia, Australia
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Abstract
One of the main problems in the treatment of rectal cancer is the development of local recurrences. In the last decades, major improvements have been realized in the surgical treatment of rectal cancer. The introduction of TME-surgery has led to a large reduction in local recurrence rates and improved survival. TME-based operations are now established as the standard of care for rectal cancer, and should form the basis for trials concerning the role of (neo)adjuvant therapy. However, training and quality control are prerequisites to obtain good results in all surgeons' hands. Furthermore, standardization in the description of operations and reporting of pathology specimens should be implemented as important features of quality control. In general, it is thought that high volume and specialist care produces superior results to low volume and non-specialist care, especially for those less frequent forms of cancer and in technically difficult operations, like those for rectal cancer. However, limiting the performance of rectal cancer surgery to highly specialized surgeons or to only those general surgeons who perform more than a certain volume is impractical in view of the prevalence of rectal cancer. This article reviews developments in the treatment of especially mobile rectal cancer and pays attention to variability in outcomes and quality assurance of surgery.
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Affiliation(s)
- E Kapiteijn
- Department of Surgery K6-R, Leiden University Medical Center, PO Box 9600, 2300 RC, Leiden, The Netherlands
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Cooper KG, Jack SA, Parkin DE, Grant AM. Five-year follow up of women randomised to medical management or transcervical resection of the endometrium for heavy menstrual loss: clinical and quality of life outcomes. ACTA ACUST UNITED AC 2001. [DOI: 10.1016/s0306-5456(01)00275-3] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Cooper KG, Jack SA, Parkin DE, Grant AM. Five-year follow up of women randomised to medical management or transcervical resection of the endometrium for heavy menstrual loss: clinical and quality of life outcomes. BJOG 2001; 108:1222-8. [PMID: 11843383 DOI: 10.1111/j.1471-0528.2001.00275.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
OBJECTIVE To assess clinical status, changes in health related quality of life, and subsequent management five years after medical management or transcervical resection of the endometrium for treatment of heavy menstrual loss. DESIGN Five year follow up using postal questionnaires and operative databank review. SETTING Gynaecology department of a large UK teaching hospital. POPULATION Women referred to the gynaecologist for treatment of heavy menstrual loss. METHODS Eligible women, without a treatment preference, were randomised equally to either medical treatment or transcervical resection of the endometrium. MAIN OUTCOME MEASURES Women's satisfaction with treatment, menstrual status, changes in health related quality of life, and additional treatments received at five years. RESULTS One hundred and forty-four patients completed questionnaires, achieving 77% follow up (medical n = 71/94; transcervical resection of the endometrium n = 73/93). At five-year follow up, 7/71 (10%) of those randomised to the medical arm still used medical treatment, while 72/94 (77%) had undergone surgical treatment and 17/94 (18%) a hysterectomy. Twenty-five (27%) women allocated to transcervical resection of the endometrium had undergone further surgery, 18/93 (19%) a hysterectomy. At five years women initially randomised to medical treatment were significantly less likely to be totally satisfied (P < 0.01, difference 21%, 95% CI -37% to -4%), or to recommend their allocated treatment to a friend (P < 0.001, difference 59%, 95% CI -73% to -45%). Bleeding and pain scores were similar in both groups and highly significantly reduced. Significantly more women in the transcervical resection of the endometrium arm had no bleeding or very light bleeding (P < 0.02, difference -22%, CI -31% to -4%), and they had significantly less days heavy bleeding (P < 0.02). Short Form 36 health survey scores were significantly improved from baseline for all eight health scales in the transcervical resection of the endometrium arm, and four in the medical arm. CONCLUSIONS A policy of immediate transcervical resection of the endometrium for women referred to a gynaecologist for treatment of heavy menstrual loss achieves higher levels of satisfaction, better menstrual status, and greater improvements in health related quality of life than medical treatment. In addition, transcervical resection of the endometrium is safe and does not lead to an increase in the number of hysterectomies. An effective endometrial ablative technique should be offered to all eligible women seeking treatment of their heavy menses from a gynaecologist.
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Affiliation(s)
- K G Cooper
- Department of Obstetrics and Gynaecology, Aberdeen Royal Infirmary, UK
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Carding P, Hillman R. More randomised controlled studies in speech and language therapy. BMJ (CLINICAL RESEARCH ED.) 2001; 323:645-6. [PMID: 11566815 PMCID: PMC1121222 DOI: 10.1136/bmj.323.7314.645] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Beard J. Regulaciones y requisitos para la introducción de nueva tecnología. ANGIOLOGIA 2001. [DOI: 10.1016/s0003-3170(01)74692-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Affiliation(s)
- P C Gøtzsche
- The Nordic Cochrane Centre Rigshospitalet Department, Copenhagen, Denmark. p.c.
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Abstract
OBJECTIVE To test whether the advantages of the ultrasonically activated shears (UAS) observed in thyroidectomies in a previous matched-pair study could be repeated in a randomized trial. SUMMARY BACKGROUND DATA The UAS has been documented, mainly in nonrandomized studies, to be a safe and fast device in video-assisted and conventional surgery. METHODS Thyroidectomies and lobectomies performed for benign or malignant thyroid disease between August 1997 and January 1999 were included in this series. Separate randomization, resulting in four sets of envelopes, was done for one consultant endocrine surgeon and for senior residents for both lobectomies and for total thyroidectomies. The operations performed with the UAS were compared with operations performed with the conventional method, using ligatures as the main hemostatic method. Main outcome measures were operating time, postoperative serum calcium level, palsy of the recurrent laryngeal nerve, and amount of intraoperative and postoperative bleeding. Possible bias that could have been caused by imbalance between treatment groups for surgeon experience was tested by two-way analysis of covariance. RESULTS Thirty-six patients were randomized, 19 to the UAS and 17 to the conventional group. Mean operating time was 99.1 minutes in the UAS group and 134.9 minutes in the conventional group. The average savings in operating time with the UAS was thus 35.8 minutes. There was no difference in complications between the groups. The estimated savings in operating time would have been 1.66 times that observed in this study if the groups had been unbalanced with reference to surgeon experience. CONCLUSION The UAS is a usable device in total thyroidectomies and lobectomies.
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Affiliation(s)
- P E Voutilainen
- Department of Surgery, Helsinki University, Central Hospital, Finland
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Lilford RJ, Braunholtz DA, Greenhalgh R, Edwards SJ. Trials and fast changing technologies: the case for tracker studies. BMJ (CLINICAL RESEARCH ED.) 2000; 320:43-6. [PMID: 10617532 PMCID: PMC1117318 DOI: 10.1136/bmj.320.7226.43] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Affiliation(s)
- R J Lilford
- Department of Public Health and Epidemiology, University of Birmingham, Birmingham B15 2TT
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Cooper KG, Bain C, Parkin DE. Comparison of microwave endometrial ablation and transcervical resection of the endometrium for treatment of heavy menstrual loss: a randomised trial. Lancet 1999; 354:1859-63. [PMID: 10584722 DOI: 10.1016/s0140-6736(99)04101-x] [Citation(s) in RCA: 127] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
BACKGROUND Various new endometrial ablation techniques have emerged for the treatment of menorrhagia. We undertook a randomised controlled trial comparing one new technique, microwave endometrial ablation (MEA), with a proven procedure, transcervical resection of the endometrium (TCRE), for women with heavy menstrual loss. METHODS 263 eligible and consenting women, referred for endometrial ablative surgery, were randomly assigned MEA (Microsulis plc, Waterlooville, Hampshire, UK; n=129) or TCRE (n=134). 230 participants were needed to give 80% power of demonstrating a 15% difference in satisfaction with treatment. All procedures were done under general anaesthesia 5 weeks after endometrial thinning with goserelin 3.6 mg. Questionnaires were completed at recruitment and at 12 months' follow-up. The primary outcome measures were patients' satisfaction with and the acceptability of treatment. Analysis was by intention to treat among women followed up to 12 months (n=116 MEA, n=124 TCRE). FINDINGS At 12 months, 89 (77%) women in the MEA group and 93 (75%) in the TCRE group were totally or generally satisfied with their treatment (95% CI for difference -12 to 17) and 109 (94%) versus 112 (90%) found it acceptable (-11 to 35). Mean operating times were shorter for MEA than for TCRE (11.4 vs 15.0 min, p=0.001) and the postoperative stay slightly but not significantly shorter. One blunt perforation occurred in each study group resulting in one immediate hysterectomy (TCRE group). Of eight health-related quality of life dimensions, all were improved after MEA (six significantly) and seven were improved after TCRE (all significantly). INTERPRETATION Both techniques achieved high rates of satisfaction and acceptability and both improved quality of life after 1 year. However, we cannot exclude a difference in satisfaction between the groups of less than 15%. MEA seems a suitable alternative to TCRE.
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Affiliation(s)
- K G Cooper
- Department of Obstetrics and Gynaecology, Aberdeen Royal Infirmary, UK
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Anderson JN, Fennessy PA, Fennessy GA, Schattner RL, Burrows EA. "Picking winners": assessing new health technology. Med J Aust 1999; 171:557-9. [PMID: 10816711 DOI: 10.5694/j.1326-5377.1999.tb123796.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Are evidence-based approaches ready for health technology?
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Affiliation(s)
- J N Anderson
- Centre for Clinical Effectiveness, Monash University, Melbourne, VIC.
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Cooper KG, Parkin DE, Garratt AM, Grant AM. Two-year follow up of women randomised to medical management or transcervical resection of the endometrium for heavy menstrual loss: clinical and quality of life outcomes. BRITISH JOURNAL OF OBSTETRICS AND GYNAECOLOGY 1999; 106:258-65. [PMID: 10426646 DOI: 10.1111/j.1471-0528.1999.tb08240.x] [Citation(s) in RCA: 65] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
OBJECTIVE To assess clinical status and changes in health related quality of life after two years in women randomised to medical management or transcervical resection of the endometrium (TCRE) for treatment of heavy menstrual loss. DESIGN Two-year follow up using postal questionnaires and operative databank review. SETTING Gynaecology department of a large UK teaching hospital. PARTICIPANTS Women who had joined a randomised comparison of medical treatment with TCRE for heavy menstrual loss two years previously. MAIN OUTCOME MEASURES Women's satisfaction with treatment, gynaecological symptoms, changes in health related quality of life, and additional treatments received at two years. RESULTS Women allocated medical treatment were significantly less likely to be totally or generally satisfied (57% vs 79%, difference -22%, 95% CI -36, -9%), to find their management acceptable (77% vs 93%, difference -16%, 95% CI -26, -4%), or to recommend their allocated treatment (24% vs 78%, difference -54%, 95% CI -61, -33%). In the medical cohort 59% of women had undergone TCRE, hysterectomy or both, whereas 17% in the TCRE cohort had undergone further surgery. Bleeding and pain scores were similar in the groups and highly significantly better than at recruitment. Short Form-36 health survey scores were significantly improved from baseline for five of the eight health scores in the medical arm, and seven in the TCRE arm. CONCLUSIONS The results at two years consolidate the findings and conclusions based on the four-month follow up data. A policy of early TCRE is effective and safe and does not result in an increase in hysterectomies. It should not be routinely withheld in an effort to try alternative medical therapies.
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Affiliation(s)
- K G Cooper
- Department of Obstetrics and Gynaecology, Aberdeen Royal Infirmary, Foresterhill, UK
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Colorectal disease. Colorectal Dis 1999; 1:59. [PMID: 23577707 DOI: 10.1046/j.1463-1318.1999.00032.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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Chalmers I. Unbiased, relevant, and reliable assessments in health care: important progress during the past century, but plenty of scope for doing better. BMJ (CLINICAL RESEARCH ED.) 1998; 317:1167-8. [PMID: 9794844 PMCID: PMC1114148 DOI: 10.1136/bmj.317.7167.1167] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Papagrigoriadis S. Prospective randomized study of laparoscopic versus open colonic resection for adenocarcinoma. Br J Surg 1997; 84:1173-4; author reply 1174-5. [PMID: 9278682 DOI: 10.1002/bjs.1800840846] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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McCall JL, Sharples K, Jadallah F. Systematic review of randomized controlled trials comparing laparoscopic with open appendicectomy. Br J Surg 1997. [DOI: 10.1002/bjs.1800840804] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Torgerson DJ, Klaber-Moffett J, Russell IT. Patient preferences in randomised trials: threat or opportunity? J Health Serv Res Policy 1996; 1:194-7. [PMID: 10180870 DOI: 10.1177/135581969600100403] [Citation(s) in RCA: 87] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
OBJECTIVES To assess whether it is feasible to elicit patients' preferences for treatments and then to proceed with randomisation which may allocate those with preferences to their less preferred treatment; and to describe which prognostic variables were associated with such preferences within the context of a randomised trial of an exercise programme for back pain. METHODS The first 97 patients enrolled in a randomised controlled trial (RCT) for the treatment of back pain were asked about their preferences, health characteristics and other prognostic variables. RESULTS Fifty-eight (60%) patients preferred to be allocated to the exercise programme whilst 38 (39%) were indifferent; one patient preferred conventional general practitioner (GP) management. No patient refused randomisation. Comparing patients preferring the exercise programme with indifferent patients showed that the former had a higher belief in the effectiveness of the new treatment (P < 0.01), tended to have worse back pain (P = 0.09), had back pain for a shorter duration (P = 0.04), and tended to have had more GP home visits (P = 0.06). CONCLUSIONS For many randomised trials preference may be an important prognostic variable. In such circumstances, preference should be taken into account in the final analysis. This study demonstrates it is sometimes feasible to randomise patients to their less preferred treatment, thus allowing more robust statistical comparisons between randomised groups. This modification may make RCTs more rigorous and improve their external validity.
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Affiliation(s)
- D J Torgerson
- National Primary Care Research and Development Centre, Centre for Health Economics, University of York, UK
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Pegg DJ. Evaluating new surgical procedures. Hip replacements come in at least 10(11) varieties. BMJ (CLINICAL RESEARCH ED.) 1996; 312:637. [PMID: 8595353 PMCID: PMC2350425 DOI: 10.1136/bmj.312.7031.637] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
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McGinn FP, Terzi C. Evaluating new surgical procedures. Few trials of laparoscopic cholecystectomy have been randomised. BMJ (CLINICAL RESEARCH ED.) 1996; 312:637. [PMID: 8595352 PMCID: PMC2350406 DOI: 10.1136/bmj.312.7031.637b] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
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Majeed AW, Johnson AG. Evaluating new surgical procedures. Design of trials should depend on whether new skills are required. BMJ (CLINICAL RESEARCH ED.) 1996; 312:637. [PMID: 8595351 PMCID: PMC2350420 DOI: 10.1136/bmj.312.7031.637a] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
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