Controlled Trials in Aesthetic Plastic Surgery: A 16-Year Analysis

Aesthetic surgery is one pillar of plastic surgery. Thus, not surprisingly, journals exist that focus predominantly on advances within this subspecialty. However, rarely has the process of systematic reviewing that identified randomized controlled trials (RCTs) and controlled clinical trials (CCTs) been conducted within this subspecialty. All original articles published in Aesthetic Plastic Surgery were analyzed to identify all RCTs and CCTs. The proportion of RCTs and CCTs in all original articles was determined, and the quality of reporting was assessed on the basis of established quality items. Additional parameters were investigated including reporting of statistically significant differences, type of institution, and country affiliation of the first author. Of the 1,048 original articles analyzed, 11 (1%) and 24 (2.3%) articles met the inclusion criteria for RCTs and CCTs, respectively. Only two studies were single blinded, whereas only one study reported on successful double blinding and appropriate allocation concealment. Notably, these trials were RCTs. Participant dropout was reported in one study. Statistically significant differences were reported in 18 trials, 6 of which were RCTs. The annual publication of RCTs has increased over the past 5 years. North America and Europe contributed a total of 28 controlled trials (80%). Controlled trials are being conducted in aesthetic surgery at a strikingly low rate. However, a recent increase in published RCTs reflects the recognition that performing outcome studies is pivotal in moving practice toward a foundation based on assessment by outcome. The quality of reporting, however, needs improvement.     

Hand searching for controlled clinical trials in German surgical journals. A contribution to evidence-based surgery]

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.     

Handsuche nach kontrollierten klinischen Studien in deutschsprachigen chirurgischen Zeitschriften

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.     

《护理学杂志》随机对照临床试验和对照试验文献评价

目的 了解我国临床护理试验研究现状，为循证医学中心护理学领域输送基线资料。方法 按中国循证医学中心手检指南逐页手工检索《护理学杂志》刊载的随机对照临床试验（Randomized Controlled Trials,RCTs)和临床对照试验（Controlled Clinical Trials,CCTs)论文，并进行描述性统计分析和研究方法学评价。结果 共检索1986－2000年15卷85期杂志3906篇文章，其中RCTs论文147篇，CCTs论文106篇，分别占杂志创刊以来文章总刊载的3．8％和2．7％。1986－2000年RCTs论文的平均发展速度和平均增长速度分别为146．8％和46．8％，CCTs论文分别为131．6％和31．6％。结论 我国临床护理试验研究还处于起步阶段，研究方法学方面尚存在不足，有待改进。     

Randomized controlled trials in nephrology: state of the evidence and critiquing the evidence

The randomized controlled trial (RCT) remains the "gold standard" for the evaluation of therapies. Despite some progress during the past decade, the number and quality of published RCTs addressing the core issues for patients with CKD and with renal diseases, in general, lag behind other areas in internal medicine. The paucity of robust evidence results in fewer patients receiving evidence-based therapies in nephrology and fewer rigorous systematic reviews to inform nephrology practice and health care policy. Because trials of lower methodologic rigor continue to be published, the evidence-based practitioner must evaluate new evidence from the medical literature carefully before incorporating that evidence into their clinical practice. The types of errors that may limit the validity or applicability of evidence from RCTs is outlined. A detailed discussion of the most important design elements for the conduct of a high-quality RCT is described in the text. These considerations are placed into the context of critical appraisal tools. These tools allow the clinician to efficiently assess the quality of published RCTs and to determine how the new RCT evidence should change current best practice.     

Negative results of randomized clinical trials published in the surgical literature: equivalency or error?

HYPOTHESIS: We hypothesized that review of randomized controlled clinical trials (RCTs) with nonstatistically significant or "negative" results published in the surgical literature do not have appropriate statistical power to demonstrate equivalency between treatment arms. DATA SOURCES AND STUDY SELECTION: The MEDLINE database was searched to obtain reports of all RCTs with negative results published in 3 surgical journals from 1988 to 1998. Manual review of one year (1997) of publications for each journal was performed to validate our search strategy. Equivalency was evaluated using the Two One-Sided Tests Procedure and post hoc power calculations. DATA SYNTHESIS: Ninety reports of RCTs with negative results were identified in the surgical literature between 1988 and 1998. The manual review of 1997 showed a 100% retrieval rate for our search strategy. After applying the Two One-Sided Tests Procedure, 35 reports (39%) met the criteria for demonstrating equivalency. The other 55 reports (61%) contained at least a 10% absolute difference in the 90% confidence interval of Delta. Using the power calculation method, only 22 (24%) articles had a power greater than.80 to detect a 50% difference in therapeutic effect. Only 29% of the reports included a formal sample size calculation and these studies were more likely to demonstrate equivalency than those without a sample size estimate (P<.01). CONCLUSIONS: Many reports from negative RCTs published in the surgical literature lack sufficient statistical power to establish that clinically important differences are not present. Surgeons should perform appropriate sample size calculations when designing RCTs and recognize the utility of confidence intervals when reporting negative results.     

2004-2009年《中华肝胆外科杂志》发表的随机对照研究分析

目的 分析2004-2009年<中华肝胆外科杂志>发表的随机对照研究(randomized control trial,RCT)情况.方法 对2004-2009年<中华肝胆外科杂志>72期杂志刊出的所有RCT文献进行统计学分析.分析指标包括收稿时间、发表时间、引文总数、中文引文数、英文引文数、基金资助情况、参研作者人数、文章所属单位等.同时,对临床RCT中单(多)中心研究情况、得出有阳性意义结论情况、研究起始时间、结束时间、病人例数等指标亦进行了提取后分析.结果 2004-2009年<中华肝胆外科杂志>共刊出RCT文章135篇,期均RCT数1.88篇,RCT在所有研究类文献中占比为8.7%.RCT研究的平均发文时滞450 d,总引文条数1252条,篇均引文数9.3条.有基金资助的RCT研究53篇,占RCT总数的39%.发表RCT最多的单位是首都医科大学附属友谊医院,为8篇.临床RCT研究中多中心研究1篇,所有临床RCT均得出有阳性意义的结论.33篇临床RCT研究篇均研究周期45.0个月,共涉及研究对象2705例,平均单篇临床RCT中研究对象数为82例.结论 <中华肝胆外科杂志>重视刊载研究证据最强、最有价值的RCT文献.此类研究对国内肝胆外科领域临床诊治和实验研究具有重要意义.     

动力髋与Gamma钉治疗成人股骨粗隆间骨折疗效的Meta分析

目的 对动力髋与Gammai钉两种内固定物治疗成人股骨粗隆间骨折的疗效进行Meta评价.方法 计算机检索MEDLINE、EMBASE、Cochrane图书馆、Cochrane协作网肌骨创伤组试验数据库和中国生物医学文献数据库,收集所有相关随机对照试验及半随机对照试验,且采用RevMan 4.2.10进行Meta分析.结果 共纳入8个随机对照试验,1个半随机对照试验.Meta分析显示,Gamma钉组术中和术后股骨干骨折的发生率明显增加,二次手术率较高.结论 与动力髋组治疗股骨粗隆间骨折相比,Gamma钉组术中和术后股骨干骨折的发生率明显增加,二次手术率更高.但两种内固定器械与拉力螺钉切割出股骨头、术区深部感染、血栓栓塞发生率等的关系尚需更多设计严格的大样本随机对照试验进一步研究.     

Factorial design provides evidence to guide practice of anaesthesia

Many scientific articles are written merely to get something published, neglecting the clinician who would like the medical literature to guide their practice. Evidence-based medicine is expected to help in clinical decision-making. Systematic reviews of the literature followed by a meta-analysis of randomized, controlled trials (RCT) have claimed to represent the highest strength of evidence. However, the results published in meta-analyses have not always been confirmed in subsequent large RCTs. An analysis of 12 large RCTs and 19 meta-analyses addressing the same questions found that the outcomes of these large RCTs were not predicted accurately 35% of the time by previously published meta-analyses. Therefore, meta-analyses of several small RCTs do not obviate the need for large, multicentre RCTs, which can still be considered as a gold standard for the development of clinical guidelines or practice plans. Moreover, large RCTs using a factorial design can be highly efficient because they can answer several clinical questions at the same time and offer the only systematic approach to investigate an interaction of combinations in multimodal approaches.     

The role of prospective randomized clinical trials in pediatric surgery: state of the art?

PURPOSE: This study sought to determine the role of randomized controlled trials (RCT) in the evolution of pediatric surgical practice. METHODS: The authors used a computer-assisted literature search to identify all clinical trials related to pediatric surgery published in the English-language literature from 1966 through 1999. Each article was reviewed in detail for purpose, content, conduct, and quality of the trial. The authors assessed quality with a previously validated instrument (Chalmers Qualitative Assessment). RESULTS: The authors identified 134 RCTs related to pediatric surgery over the past 33 years. This accounts for 0.17% of 80,377 articles published in the field. The areas of surgery studied were analgesia 65 (49%), antibiotics 17 (13%), extracorporeal membrane oxygenation (ECMO) 9 (7%), gastrointestinal, burns, oncology, minimally invasive surgery, vascular access, congenital anomalies, and trauma (each <5%). Only 16 (12%) trials compared 2 surgical therapies, 9 (7%) compared a medical versus a surgical therapy, and 109 (81%) compared 2 medical therapies in surgical patients. Fourteen (10%) RCTs were funded by peer-reviewed agencies. Only 17 (13%) RCTs included a biostatistician as an author or a consultant. Trial design included calculation of sample size and statistical power in 21 (16%) RCTs. Method of randomization was reported in only 51 (38%). The test statistic and observed probability value was reported in 15 (11%). CONCLUSIONS: Clinical trials are used infrequently to answer questions related to pediatric surgery. When RCTs are utilized, they often suffer from poor trial design, inadequate statistical analysis, and incomplete reporting. Pediatric surgery could benefit from increased expertise, funding, and participation in clinical trials.     

An Evaluation of Spin in Lower Extremity Joint Trials

Background

Spin is a specific type of reporting bias that misrepresents data and results within randomized controlled trials (RCTs). Because spin may provide a surgeon with an inaccurate representation of trial results, thus misconstruing the surgeons' interpretation thereof and possibly negatively affecting patient care, it is important that spin is identified within publications. The primary goal of our study was to determine the prevalence of spin found within the abstracts of lower extremity joint trials.

Surgical research revisited: clinical trials in the cardiothoracic surgical literature.

OBJECTIVE: Surgeons have been criticised for not undertaking high-quality research. This study examines the quality of randomised controlled trials (RCTs) in the cardiothoracic surgical literature with a view to revisiting the role of RCTs in surgical research. METHODS: All RCTs published in 1998 and 1999 in three major international cardiothoracic journals were analysed for basic components of trial design and presentation. RESULTS: We found 119 papers presented as RCTs. The median size of treatment arms per RCT was 20 (interquartile range 14-40). Of 20 dimensions of trial quality examined, 12 or more were deficient (not described or performed inadequately) in half of the studies. Key information was frequently missing. Additionally, most trials relied on 'soft' endpoints, using surrogate (72, 61%) rather than clinical, and numerical (102, 86%) rather than categorical outcomes suggesting lack of power to detect clinically relevant differences. Although most trials reported positive results (73, 63%), only in 18 (15%) did authors make recommendations for practice change. CONCLUSIONS: Many RCTs in surgery by virtue of their design, sample size, and insufficient power are incapable of answering the questions researchers seek to address. Surgical trials often may not exclude bias because of lack of blinding and variations in surgical technique and performance. It is arguable that for most study questions in clinical surgery, comparative analysis of large case series and databases will provide more robust evidence.     

Randomized controlled trials in neurosurgery—how good are we?

Summary 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.     

Sample size calculations in surgery: are they done correctly?

BACKGROUND: Randomized controlled trials (RCTs) are considered the gold standard for evidence-based clinical research, but prior work has suggested that there may be poor reporting of sample sizes in the surgical literature. Sample size calculations are essential for planning a study to minimize both type I and type II errors. We hypothesized that sample size calculations may not be performed consistently in surgery studies and, therefore, many studies may be "underpowered." To address this issue, we reviewed RCTs published in the surgical literature to determine how often sample size calculations were reported and to analyze each study's ability to detect varying degrees of differences in outcomes. METHODS: A comprehensive MEDLINE search identified RCTs published in Annals of Surgery, Archives of Surgery, and Surgery between 1999 and 2002. Each study was evaluated by two independent reviewers. Sample size calculations were performed to determine whether they had 80% power to detect differences between treatment groups of 50% (large) and 20% (small), with one-sided test, alpha = 0.05. For the underpowered studies, the degree to which sample size would need to be increased was determined. RESULTS: One hundred twenty-seven RCT articles were identified; of these, 48 (38%) reported sample size calculations. Eighty-six (68%) studies reported positive treatment effect, whereas 41 (32%) found negative results. Sixty-three (50%) of the studies were appropriately powered to detect a 50% effect change, whereas 24 (19%) had the power to detect a 20% difference. Of the studies that were underpowered, more than half needed to increase sample size by more than 10-fold. CONCLUSIONS: The reporting of sample size calculations was not provided in more than 60% of recently published surgical RCTs. Moreover, only half of studies had sample sizes appropriate to detect large differences between treatment groups.     

A guide to planning and executing a surgical randomized controlled trial

Evidence-based medicine requires that treatments given to patients demonstrate effectiveness. The randomized controlled trial (RCT) has become the preeminent study design to assess the efficacy of treatments. Randomized controlled trials are frequently used to evaluate pharmaceutical treatments but are less often used in surgery. The lack of surgical RCTs is partly due to ethical and methodological concerns associated with surgical interventions. We provide a guide to planning and conducting a surgical RCT.     

Demographic analysis: an update of randomized controlled studies in prostatic oncology

Introduction:

Results from randomized trials are least prone to systematic bias and represent the highest level of evidence in medical practice. We carried out a demographic analysis examining randomized controlled trials (RCTs) in prostate cancer. Particular emphasis was placed on newly conducted phase II/III RCTs between January 1997 and March 2006.

Methods:

We searched the MEDLINE database using the heading “prostate neoplasms” between January 1997 and March 2006. The results were then crossed with the MeSHs “Clinical trial.mp. OR clinical trial.pt. OR random:.mp. OR tu.xs;” this cross-checking is considered an optimal search strategy for detecting RCTs in MEDLINE® literature. The search yielded 7831 articles in total for the defined period. Of this total number, 7314 articles were manually analyzed and excluded as they did not represent RCTs. The qualifying 517 articles were then analyzed with emphasis on modality of therapy, cohort size, principal author, participating country and journal type.

Results:

Among the 517 randomized trials, most trials investigated medical therapies (42.7%). This was followed by diagnostic studies (13.2%), while the remaining categories made up 44.1%. A trend towards more completed RCTs is noted in the later years of the cohort. Cohort sizes were generally greater than 100 participants (63.1%). Urologists were the lead investigators in 48.2% of the trials. Trials were largely conducted in Europe and the United States (43.1% and 38.3%, respectively). About 7% of studies were based in Canada. Articles were generally published in surgical journals (48.4%), followed by medical journals (36.9%).

Conclusions:

Given that initial searches yielded nearly 8000 articles listed as RCTs in prostatic oncology, only a small percentage (5.4% to 8.6%) of these were actually RCTs which reported novel results. Most of the published data were either review articles or commentaries. It is abundantly clear that new recruitment strategies need to be developed to encourage patients to enrol in RCTs and that such studies need to be undertaken in urologic oncology to provide definitive answers to the abundant and unanswered questions in urologic oncology.     

The fragility of statistically significant findings in randomised controlled anaesthesiology trials: systematic review of the medical literature

The fragility index (FI), the number of events the statistical significance a result depends on, and the number of patients lost to follow-up are important parameters for interpreting randomised clinical trial results. We evaluated these two parameters in randomised controlled trials in anaesthesiology. For this, we performed a systematic search of the medical literature, seeking articles reporting on anaesthesiology trials with a statistically significant difference in the primary outcome and published in the top five general medicine journals, or the top 15 anaesthesiology journals. We restricted the analysis to trials reporting clinically important primary outcome measures. The search identified 139 articles, 35 published in general medicine journals and 104 in anaesthesiology journals. The median (inter-quartile range) sample size was 150 (70–300) patients. The FI was 4 (2–17) and 3 (2–7), and the number of patients lost to follow-up was 0 (0–18) and 0 (0–6) patients in trials published in general medicine and anaesthesiology journals, respectively. The number of patients lost to follow-up exceeded the FI in 41 and 27% in trials in general medicine journals and anaesthesiology journals, respectively. The FI positively correlated with sample size and number of primary outcome events, and negatively correlated with the reported P-values. The results of this systematic review suggest that statistically significant differences in randomised controlled anaesthesiology trials are regularly fragile, implying that the primary outcome status of patients lost to follow-up could possibly have changed the reported effect.