Limitations of Evidence-based Medicine: The Role of Experience and Expert Opinion

BACKGROUND:: Advances in statistical science and the development of computers (a result of the digital revolution) have allowed many disciplines, including medicine, to develop a more objective analysis of data as applied to decision making. The concept of evidence-based medicine (EBM) includes that scientific study of disease and treatment efficacy will allow high-quality, cost-effective treatment. The concept of EBM is well established in medical specialties, particularly for cardiovascular disease and cancer, but less developed in the surgical specialties. Multiple factors make evidence-based surgical (EBS) studies more problematic. Entering children into prospective surgical treatment trials remains difficult for the parents and patients who are asked to allow a choice of procedures for a surgical intervention that will take just an hour or two but whose results could change the child's entire life. Comparative effectiveness research, a subset of EBM, is of special interest to surgeons, who often need to decide on an expensive new implant versus a reliable, less expensive, established one. Factors that make the scientific analysis of surgical treatment efficacy more difficult include issues as practical as surgical skill. Prescribing an antihypertensive medication or a lipid-lowering drug has little variability in its delivery. Performance of a complex surgical procedure can vary immensely, allowing a procedure to be very effective in one surgeon's hands but far less applicable by another surgeon (eg, arthroscopic vs. open shoulder surgery). Thus, large patient series with careful follow-up are required to clarify outcome differences. Scientific study of surgical treatment outcomes in childhood orthopaedic conditions remains in its infancy. Because of minimal funding available for such research, most available studies are poorly designed with an inadequate study sample size. As for the near future, neither the government nor industry sources seem to have a strong incentive to study outcomes in childhood surgical diseases that have a low prevalence. Because current research provides little evidence to guide parents and their surgeon (when a choice exists), consumers generally seek what they believe to be the best available "expert opinion." CONCLUSIONS:: Properly funded, the digital revolution will allow radical advances in establishing EBS decision making. However, the same digital revolution has produced an educated populace, greatly increasing their capacity for critical analysis of available data. Currently, both sophisticated parents and their surgeons remain hesitant to accept results from poorly designed studies when deciding on surgery for their child. As a result, expert opinion remains central to surgical decision making in children's orthopaedics. Knowledgeable surgeons look forward to future quantum improvements in research quality that will allow secure EBS-based decisions for their surgical patients.     

循证医学与麻醉学

循证医学是近年来发展起来的一门新兴科学 ,是对传统经验医学的挑战。现已广泛应用于临床各个领域。现就循证医学的内容、方法及其在麻醉学研究中的应用作一综述。     

Role of Hypothermia in Adult Cardiac Surgery Patients: A Systematic Review and Meta-analysis

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History and Development of Evidence-based Medicine

This article illustrates the timeline of the development of evidence-based medicine (EBM). The term “evidence-based medicine” is relatively new. In fact, as far as we can tell, investigators from McMaster’s University began using the term during the 1990s. EBM was defined as “a systemic approach to analyze published research as the basis of clinical decision making.” Then in 1996, the term was more formally defined by Sacket et al., who stated that EBM was “the conscientious and judicious use of current best evidence from clinical care research in the management of individual patients.” Ancient era EBM consists of ancient historical or anecdotal accounts of what may be loosely termed EBM. This was followed by the development of the renaissance era of EBM, which began roughly during the seventeenth century. During this era personal journals were kept and textbooks began to become more prominent. This was followed by the 1900s, during an era we term the transitional era of EBM (1900–1970s). Knowledge during this era could be shared more easily in textbooks and eventually peer-reviewed journals. Finally, during the 1970s we enter the modern era of EBM. Technology has had a large role in the advancement of EBM. Computers and database software have allowed compilation of large amounts of data. The Index Medicus has become a medical dinosaur of the past that students of today likely do not recognize. The Internet has also allowed incredible access to masses of data and information. However, we must be careful with an overabundance of “unfiltered” data. As history, as clearly shown us, evidence and data do not immediately translate into evidence based practice.     

Evidence-based Medicine in Surgical Decision Making

There are now five classic steps for analysis of diagnostic and therapeutic medical decision-making policies: (1) formulate a clear clinical question based on a particular patient’s problem; (2) search the literature for relevant clinical articles; (3) evaluate the evidence for its validity and usefulness; (4) implement useful findings into clinical practice; (5) audit the validity of the process. The clinician must have the necessary skills to appraise critically the information retrieved. Rather than focusing on the discussion and conclusion sections of articles, the reader should concentrate on the review of the methods and results sections to formulate an opinion regarding the strength of evidence presented in the paper. The process is intellectually demanding and difficult to achieve. This particular step in the validation of evidence implies that each clinician must be methodologically and statistically sound, an “expert,” capable of analyzing the method used in that particular publication to achieve the published result.     

Quality Control in Systematic Reviews and Meta-analyses

Systematic reviews and meta-analyses are being submitted to, and being published by biomedical journals with increasing frequency. In order to maintain the utility of such publications and avoid misguidance it is important that these studies are conducted to a high standard. This article aims to provide guidance both for those researchers undertaking and reporting such studies and for the readers of such articles. Details of a suggested method for conducting a systematic review are given, including methods for literature searches, data abstraction and data extraction followed by a brief overview of common methods used for meta-analyses and the interpretation of the results of meta-analysis.     

证据医学(EBM)的原理及在临床营养研究中的应用

证据医学的原理2 0世纪 80年代以前的临床研究常以血压、血细胞、血生化、代谢变化等作为有效性指标 ,而其后的临床研究发现单用这些替代性指标 (ｓｕｒｒｏｇａｔｅｐａｒａｍｅｔｅｒｓ)是不够的 ,需以病人的预后 (包括死亡率、并发症发生率、住院时间和住院费用等 )、对病人生活质量的影响及对卫生经济学指标的作用如效益 -费用比 (ｅｆｆｅｃｔ-ｃｏｓｔｒａｔｉｏ)等来评估某种治疗方法的效果。 2 0世纪 80年代后 ,“证据”的观点被引入临床研究领域[1～ 4 ] ,其评估模式体现了科学治疗的概念 ,即科学治疗是既有客观效果 ,又要节省费用…     

Systematic Review and Meta-analysis of Complications in Transvaginal Approach in Laparoscopic Surgery

Transvaginal access is the most popular natural orifice translumenal technique in the minimally invasive surgery. Reviews on non-gynecological transvaginal approach morbidities reveal that rates vary greatly. A systematic review of transvaginal approach in non-gynecological intraabdominal procedures was carried out to assess the risk of complications. A systematic search was conducted using MEDLINE, EMBASE, PubMed, and the Cochrane Library from the inception of these databases to March 2012. The following keywords were searched: “transvaginal”, “NOTES”, “single incision”, and “single port”. From the total of 231 potentially eligible abstracts, 87 papers were retrieved and evaluated as fulfilling the eligibility criteria. The final analysis included 32 articles. The overall complications rate was 4.4 %, and complications related to the transvaginal port reached 2.4 %. Conversion rate to open surgery was 3.4 %. The incidence of postoperative urinary tract infection was 0.8 %. The mean operative time was 119 min. The mean hospital stay was 3.1 days (range 6 h–12 days). The technique of transvaginal access can offer several advantages for a patient and is associated with an acceptable rate of complications.     

Evidence-based Medicine: Not a Slam Dunk

Evidence-based medicine is not easy. Some difficulties are obvious, such as the difficulty to mount a powerful random prospective controlled study. This article, however, will deal with 2 types of not-so-obvious, difficulties that plague clinicians who advocate evidence-based medicine. The first type has to do with our knowledge base. We tend to think of our knowledge base as being a collection of facts that represent absolute truth and are completely dependable now and will be for the future. It is more likely that these facts are better thought of as beliefs that are fragile and about which we should be skeptical. The second type of difficulty has to do with the human brain and its ability to reach valid decisions. Let us first consider difficulties with establishing good outcome measures that are essential for good evidence.     

Evidence-based Medicine: Management of Pediatric Forearm Fractures

Forearm fractures are common injuries in the pediatric population. Successful treatment of these fractures should result in complication-free functional pronosupination. Traditionally, these have been treated with closed reduction and casting, but the last several decades have seen a dramatic increase in the operative treatment of these fractures. However, little high-level evidence exists to guide management. The data from the limited set of studies available suggest that closed treatment does usually result in satisfactory outcomes, particularly in younger patients; operative fixation is usually successful as well but comes with a significantly increased complication rate. The ideal study to aid in evidence-based decision-making for pediatric forearm fractures would be a randomly controlled trial comparing closed reduction and casting versus intramedullary nailing versus plating; in children ranging from 8 years old to skeletally mature; with closed forearm fractures, complete or greenstick with >20 degrees of angulation; with a minimum of 5 years of follow-up (or to maturity); with the primary outcome defined as final pronation and supination; using an validated functional outcome tool; and precisely defining the complications from each treatment.     

Systematic Review and Meta-analysis of Laparoscopic Versus Open Distal Gastrectomy

Background

Laparoscopic distal gastrectomy has been increasingly utilized in the treatment of gastric adenocarcinoma. This study aims to compare the morbidity/mortality and postoperative outcomes of laparoscopic-assisted versus open distal gastrectomy since 2000.

Methods

A comprehensive search of MEDLINE and EMBASE was conducted including studies published between 2000 and present.

Results

Seventeen studies with a total of 7,109 distal gastrectomies (3,496 lap vs 3,613 open) were included. Across all studies, postoperative morbidity rates for laparoscopic gastrectomy were lower than that of open [median (range) 10 (0–36)?% vs 17 (0–43)?%]. Meta-analysis of postoperative morbidity rates in prospective studies only yielded pooled odds ratio of 0.52 (95 % CI 0.33–0.81) (P?=?0.004). In-hospital mortality rates were comparable between the two (range: laparoscopic 0–3.3 vs open 0–6.7 %). The long-term oncological outcomes of resection were difficult to analyze given variable reporting but appeared similar between the two. Meta-analysis of prospective studies showed that laparoscopic-assisted distal gastrectomy was associated with significantly shorter hospital length of stay [standard mean difference (SMD)?=??0.78 (95 % CI?=??1.0 to ?0.56)], comparable intraoperative bleeding [SMD?=?0.64 (95 % CI?=??1.3–0.0430) P?=?0.066] and longer operative time compared to open gastrectomy [1.9 (95 % CI 0.05–3.8) P?=?0.045, with P?<?0.001].

Conclusion

This study supports the use of laparoscopic-assisted distal gastrectomy for treatment of gastric adenocarcinoma with evidence of comparable, if not better, short-term postoperative parameters when compared to open distal gastrectomy. The long-term oncological outcomes appear similar but may require more evaluation.     

机器人辅助与传统心脏搭桥手术的Meta分析

目的:目前,冠脉搭桥手术仍以传统正中开胸为主,但各种微创手术正在快速发展.机器人辅助的冠脉搭桥手术已逐渐开展,但其应用仍然存在争议,且缺乏高质量的证据.本研究应用Meta分析比较现有文献中使用达芬奇机器人的冠脉搭桥与非机器人冠脉搭桥手术的差异.方法:检索PubMed和The Cochrane Library数据库,收集相关临床研究,检索时限为建库至2021年7月.由2名研究者独立筛选文献、提取资料,并对纳入的文献进行偏倚风险评估.采用RevMan 5.3软件进行Meta分析.结果:纳入16项临床研究,共1467198例患者,其中机器人心脏搭桥(Robot-assisted coronary artery bypass,RCAB)组20879例,非机器人搭桥(Non-RCAB)组1446319例.两组患者术前各项指标未见显著差异.RCAB组患者的术后并发症(卒中、感染、肾衰竭、输血、院内死亡)发生率显著低于Non-RCAB组,机械通气时间、ICU停留时间和住院时间较Non-RCAB组短,手术时间短于Non-RCAB组,但差异无统计学意义.结论:Meta分析结果显示,RCAB手术比Non-RCAB在术后并发症、机械通气时间、ICU停留时间和住院时间方面具有优势,但其他围术期指标以及短期和长期预后还需要高质量的临床对照研究.