[Surgical clinical studies and their practical realization]

Randomized controlled trials in neurosurgery--how good are we?

BACKGROUND

The strongest evidence in medical clinical literature is represented by randomized controlled trials (RCTs). This study was designed to evaluate neurosurgically relevant RCTs published recently by neurosurgeons.

METHOD

A literature search in MEDLINE and EMBASE included all clinical studies published up to 30 June 2006. RCTs with neurosurgical relevance published by at least one author with affiliation to a neurosurgical department were selected. The number and characteristics of individual trials were recorded, and the quality of the trials with regard to study design, quality of reporting, and relevance for clinical practice was assessed by two different investigators using a modification of the Scottish Intercollegiate Guidelines Network methodology checklist. Changes of RCT quality over time as well as factors influencing the quality were analyzed.

FINDINGS

From the initial search results (MEDLINE n = 3,860, EMBASE n = 3,113 articles), 159 RCTs published by neurosurgeons were extracted for final evaluation. Of the RCTs, 62% have been published since 1995; 52% came from the USA, UK, and Germany. The median RCT sample size was 78 patients and the median follow-up 35.7 weeks. Fifty-two percent of all RCTs were of good, 37% of moderate, and 11% of bad quality, with an improvement over time. RCTs with financial funding and RCTs with a sample size of >78 patients were of significantly better quality. There were no major differences in the rating of the studies between the two investigators.

CONCLUSIONS

Only a fraction of neurosurgically relevant literature consists of RCTs, but the quality is satisfying and has significantly improved over the last years. An adequate sample size and sufficient financial support seem to be of substantial importance with regard to the quality of the study. Our data also show that by using a standardized checklist, the quality of trials can be reliably assessed by observers of different experience and educational levels.

[The curriculum for rotation physicians within the CHIR-Net]

INTRODUCTION

CHIR-Net is a German national surgical network for clinical trials. It is supported by the Federal Ministry for Education and Research (BMBF 01GH0605) to establish infrastructure and expertise in the conduct of clinical trials within the surgical disciplines. An important aspect of this network is a qualified advanced training for physicians deployed at the CHIR-Net as part of a job rotation.

METHODS

A catalog of activities for the time of rotation within the network has been developed in cooperation with the CHIR-Net, the deployed physicians and cooperating regional clinical trials centers (ZKS/KKS).

RESULT

The focal points of the physicians' rotation in the CHIR-Net are outlined in a curriculum that has been established and evaluated in the network since January 2008.

CONCLUSION

After the rotation time at the CHIR-Net the skilled physicians act as multipliers of specialized knowledge on clinical research. In this way the acquired expertise will be transferred into clinical practice and treatment of patients within research projects will benefit directly.

Will the dilemma of evidence-based surgery ever be resolved?

Exponents of evidence-based medicine do not undermine the importance of clinical expertise and skills, but they emphasize that decision-making in medicine should be based on the best available evidence derived from the systematic analysis of observations made in an objective, unbiased and a reproducible fashion. The randomized controlled trial (RCT) is the most scientifically rigorous means of hypothesis testing in epidemiology. Discrepancies between established surgical and other interventions and best available evidence are common. These can be in the form of significant delay in adopting a new intervention despite strong supportive evidence, adopting an intervention before supportive evidence becomes available for reasons of novelty or pear pressure and the lack of supportive evidence for many established common practices. This is compounded further by the paucity of good quality evidence for most surgical procedures. This is arguably because of the inherent difficulties in conducting surgical RCT. The practical, ethical and financial ramifications are complex and the nature of surgical disease often compromise the chances of success or completion of RCT. Carrying out surgical RCT may have more implications on the clinician's authority, autonomy and income and their results are more likely to be influenced by his/her expertise and competence than medical RCT. Furthermore, the success of surgical RCT is often jeopardized by very low recruitment rates. The aim of this study is to discuss the dilemma of producing evidence in surgery.

Role of Systematic Reviews and Meta-analysis in Evidence-based Medicine

The overwhelming increase in the quantity of clinical evidence has led to detachment of the evidence and practice because new evidence can be integrated into clinical practice only after it has been critically appraised and synthesized on the basis of the existing evidence. Because many clinicians lack the skills and the time for such information processing, systematic reviews and meta-analyses, their quantitative counterparts, play an important role in health care. Well performed systematic reviews provide clinically relevant information for surgeons, abrogating the need to identify, read, and evaluate many individual studies. This article reviews the basic principles of meta-analysis, discusses its potential weaknesses such as heterogeneity and publication bias, and highlights special situations when dealing with surgical trials.

The Study Centre of the German Surgical Society--rationale and current status

BACKGROUND

The concept of evidence-based medicine was introduced into surgery in the mid-1990s, initially focussing on the integration of best research evidence, surgeons' expertise and patients' value. The lack of relevant external evidence [randomised controlled trials (RCTs), systematic reviews] in favour of surgical procedures has led to the need for a new approach in clinical research.

DESIGN

Development and implementation of the Study Centre of the German Surgical Society (SDGC) in order to design, perform and analyse multicentre randomised controlled trials in surgery.

RESULTS

The German Surgical Society has recently initiated four surgical RCTs within the SDGC in order to improve the national infrastructure for clinical research and its international scientific standing. All surgical trials focus on procedures in various fields (thyroid and parathyroid diseases, pancreatic surgery, abdominal wall closure) and are designed to fit the specific needs of each study (blinding of patients and assessors, ranking of endpoints, patients' perspective). Additionally, in a nationwide survey of 1,274 surgical departments in Germany, 307 replied, of which 237 (19%) were willing to participate in multicentre projects.

CONCLUSION

Evidence-based medicine has changed surgical practice, leading to an increase in demand for RCTs and requiring a new infrastructure in surgical departments and scientific societies.

Evidence-based medicine in HBP surgery: is there any?

BACKGROUND

Evidence-based medicine (EBM) has become widely accepted as a basis for clinical decision in many fields of medicine. This review examines the specific role of EBM in hepato-biliary and pancreatic (HBP) surgery. EBM relies on four main sources, including clinical guidelines, meta-analyses, primary information and clinical experience. Randomized controlled trials (RCTs) constitute the cornerstone of EBM and a recent study reported that there are relatively few RCTs evaluating the effectiveness of surgical therapies and procedures (1,530 out of 45,342 or 3.4% in five leading surgical journals) and only a few in HBP surgery. Although the effort must be to implement EBM as far as possible in HBP surgery, there are several obstacles to conducting RCTs in HBP surgery, including problems associated with standardization of surgical skills, sham-operations often impossible to perform, and the general applicability of specific findings may be uncertain.

DISCUSSION

This paper will provide two relevant examples of EBM in HBP surgery in patients with hepatic metastases and pancreatic adenocarcinoma, illustrating some problems but also the potential of introducing EBM in HBP surgery. In the future, our effort must be devoted to implementing EBM in applicable areas of HBP surgery but also remembering that in certain areas accumulated knowledge from observational studies, including drainage of abscesses and surgical treatment of intestinal obstruction, may have similar or even higher clinical value than RCTs.

Perspectives of evidence-based surgery

The assessment of the optimal treatment option based on best current knowledge is called evidence-based medicine (EBM). Considering the cost explosion in public health systems, EBM should also incorporate proper utilization of the restricted economical resources and should enforce quality assurance in medicine. It is imperative that surgeons realize that randomized controlled trials are applicable to the operative specialties in a large scale, and are necessary to provide evidence-based surgery. So far, only 3.4% of all publications in the leading surgical journals are randomized controlled trials. Furthermore, only 44.1% of the published surgical randomized controlled studies compared different surgical procedures, whereas 55.9% of the articles compared medical therapies in surgical patients. Evidence-based surgical therapy is essential for further development of a high- quality surgical standard, which will also provide quality assurance in future surgical care. This article presents the definition of EBM and discusses specific problems involved in the introduction of its principles into the surgical discipline.