Trials - Most accessed articles

Factors contributing to therapeutic effects evaluated in acupuncture clinical trials

Guang-Xia Shi — 2012-04-21T00:00:00Z

Acupuncture treatment has been widely used for many conditions, while results of the increasing numbers of randomized trials and systematic reviews remain controversial. Acupuncture is a complex intervention of both specific and non-specific factors associated with therapeutic benefit. Apart from needle insertion, issues such as needling sensation, psychological factors, acupoint specificity, acupuncture manipulation, and needle duration also have relevant influences on the therapeutic effects of acupuncture. Taking these factors into consideration would have considerable implications for the design and interpretation of clinical trials.

Managing clinical trials

Barbara Farrell — 2010-07-13T00:00:00Z

Managing clinical trials, of whatever size and complexity, requires efficient trial management. Trials fail because tried and tested systems handed down through apprenticeships have not been documented, evaluated or published to guide new trialists starting out in this important field. For the past three decades, trialists have invented and reinvented the trial management wheel. We suggest that to improve the successful, timely delivery of important clinical trials for patient benefit, it is time to produce standard trial management guidelines and develop robust methods of evaluation.

Impact assessment of the European Clinical Trials Directive: a longitudinal, prospective, observational study analyzing patterns and trends in clinical drug trial applications submitted since 2001 to regulatory agencies in six EU countries

Markus Hartmann — 2012-04-29T00:00:00Z

Background: Shifts in clinical trial application rates over time indicate if the attractiveness of a country or region for the conduct of clinical trials is growing or decreasing. The purpose of this observational study was to track changes in drug trial application patterns across several EU countries in order to analyze the medium-term impact of the EU Clinical Trials Directive 2001/20/EC on the conduct of drug trials. Methods: Rates of Clinical Trial Applications (CTA) for studies with medicinal products in those six countries in the EU, which authorize on average more than 500 trials per year, were analyzed. Publicly available figures on the number of annually submitted CTA, the distribution of trials per phase and the type of sponsorship were tracked; missing data were provided by national drug agencies. Results: Since 2001, the number of CTA in Italy and Spain increased significantly (5.0 and 2.5% average annual growth). For Italy, the gain was driven by a strong increase of applications from academic trial sponsors; Spain's growth was due to a rise in trials run by commercial sponsors. The Netherlands, Germany, France and the UK saw a decline (1.9, 2.3, 3.0 and 5.3% average annual diminution; significant (P < 0.05) except for Germany) in clinical drug trials. The decrease in the UK was caused by a sharp fall in academic trial activities. Across the six analyzed countries, no EU-wide trial-phase-specific patterns or trends were observed. Conclusions: The EU Clinical Trials Directive 2001/20/EC did not achieve the harmonization of clinical trial requirements across Europe. Rather, it resulted in the leveling of clinical trial activities caused by a continuing decrease in CTA rates in the Netherlands, Germany, France and the UK. Southern European countries, Italy and Spain, benefited to some extent from policy changes introduced by the Directive. In Italy's case, national funding measures helped to considerably promote the conduct of non-commercial trials. On the other hand, the EU Directive-driven transition from liberal policy environments, based on non-explicit trial approval through notifications, towards red-taped processes of trial authorization, contributed to the decreases in trial numbers in Germany and the UK. In the latter case, national research governance concerns had a share in the country's marked decline. However, different EU member states successfully developed best practices, which a new European legislation should take into consideration to resume Europe's attractiveness and international competitiveness for the conduct of clinical trials.

Reporting bias in medical research - a narrative review

Natalie McGauran — 2010-04-13T00:00:00Z

Reporting bias represents a major problem in the assessment of health care interventions. Several prominent cases have been described in the literature, for example, in the reporting of trials of antidepressants, Class I anti-arrhythmic drugs, and selective COX-2 inhibitors. The aim of this narrative review is to gain an overview of reporting bias in the medical literature, focussing on publication bias and selective outcome reporting. We explore whether these types of bias have been shown in areas beyond the well-known cases noted above, in order to gain an impression of how widespread the problem is. For this purpose, we screened relevant articles on reporting bias that had previously been obtained by the German Institute for Quality and Efficiency in Health Care in the context of its health technology assessment reports and other research work, together with the reference lists of these articles.We identified reporting bias in 40 indications comprising around 50 different pharmacological, surgical (e.g. vacuum-assisted closure therapy), diagnostic (e.g. ultrasound), and preventive (e.g. cancer vaccines) interventions. Regarding pharmacological interventions, cases of reporting bias were, for example, identified in the treatment of the following conditions: depression, bipolar disorder, schizophrenia, anxiety disorder, attention-deficit hyperactivity disorder, Alzheimer's disease, pain, migraine, cardiovascular disease, gastric ulcers, irritable bowel syndrome, urinary incontinence, atopic dermatitis, diabetes mellitus type 2, hypercholesterolaemia, thyroid disorders, menopausal symptoms, various types of cancer (e.g. ovarian cancer and melanoma), various types of infections (e.g. HIV, influenza and Hepatitis B), and acute trauma. Many cases involved the withholding of study data by manufacturers and regulatory agencies or the active attempt by manufacturers to suppress publication. The ascertained effects of reporting bias included the overestimation of efficacy and the underestimation of safety risks of interventions.In conclusion, reporting bias is a widespread phenomenon in the medical literature. Mandatory prospective registration of trials and public access to study data via results databases need to be introduced on a worldwide scale. This will allow for an independent review of research data, help fulfil ethical obligations towards patients, and ensure a basis for fully-informed decision making in the health care system.

Should we reconsider the routine use of placebo controls in clinical research?

Andrew Avins — 2012-04-27T00:00:00Z

Background: Modern clinical-research practice favors placebo controls over usual-care controls whenever a credible placebo exists. An unrecognized consequence of this preference is that clinicians are more limited in their ability to provide the benefits of the non-specific healing effects of placebos in clinical practice. Methods: We examined the issues in choosing between placebo and usual-care controls. We considered why placebo controls place constraints on clinicians and the trade-offs involved in the choice of control groups. Results: We find that, for certain studies, investigators should consider usual-care controls, even if an adequate placebo is available. Employing usual-care controls would be of greatest value for pragmatic trials evaluating treatments to improve clinical care and for which threats to internal validity can be adequately managed without a placebo-control condition. Conclusions: Intentionally choosing usual-care controls, even when a satisfactory placebo exists, would allow clinicians to capture the value of non-specific therapeutic benefits that are common to all interventions. The result could be more effective, patient-centered care that makes the best use of both specific and non-specific benefits of medical interventions.

CONSORT 2010 Statement: updated guidelines for reporting parallel group randomised trials

Kenneth Schulz — 2010-03-24T00:00:00Z

The CONSORT statement is used worldwide to improve the reporting of randomised controlled trials. Kenneth Schulz and colleagues describe the latest version, CONSORT 2010, which updates the reporting guideline based on new methodological evidence and accumulating experience.To encourage dissemination of the CONSORT 2010 Statement, this article is freely accessible on bmj.com and will also be published in the Lancet, Obstetrics and Gynecology, PLoS Medicine, Annals of Internal Medicine, Open Medicine, Journal of Clinical Epidemiology, BMC Medicine, and Trials.

The effect of telephone-based interpersonal psychotherapy for the treatment of postpartum depression: study protocol for a randomized controlled trial

Cindy-Lee Dennis — 2012-04-19T00:00:00Z

Background: Substantial data indicate potential health consequences of untreated postpartum depression (PPD) on the mother, infant, and family. Studies have evaluated interpersonal psychotherapy (IPT) as treatment for PPD; however, the results are questionable due to methodological limitations. A comprehensive review of maternal treatment preferences suggests that mothers favor 'talking therapy' as a form of PPD treatment. Unfortunately, IPT is not widely available, especially in rural and remote areas. To improve access to care, telepsychiatry has been introduced, including the provision of therapy via the telephone. Methods: The purpose of this randomized controlled trial is to evaluate the effect of telephone-based IPT on the treatment of PPD. Stratification is based on self-reported history of depression and province. The target sample is 240 women. Currently, women from across Canada between 2 and 24 weeks postpartum are able to either self-identify as depressed and refer themselves to the trial or they may be referred by a health professional based on a score >12 on the Edinburgh Postnatal Depression Scale (EPDS). Following contact by the trial coordinator, a detailed study explanation is provided. Women who fulfill the eligibility criteria (including a positive diagnostic assessment for major depression) and consent to participate are randomized to either the control (standard postpartum care) or intervention group (standard postpartum care plus 12 telephone-based IPT sessions within 12 to 16 weeks, provided by trained nurses). Blinded research nurses telephone participants at 12, 24, and 36 weeks post-randomization to assess for PPD and other outcomes including depressive symptomatology, anxiety, couple adjustment, attachment, and health service utilization. Results from this ongoing trial will: (1) develop the body of knowledge concerning the effect of telephone-based IPT as a treatment option for PPD; (2) advance our understanding of training nurses to deliver IPT; (3) provide an economic evaluation of an IPT intervention; (4) investigate the utility of the EPDS in general clinical practice to identify depressed mothers; and (5) present valuable information regarding PPD, along with associated couple adjustment, co-morbid anxiety and self-reported attachment among a mixed rural and urban Canadian population.Trial registrationCurrent Controlled Trials Ltd. ISRCTN88987377.

Thrombelastographic haemostatic status and antiplatelet therapy after coronary artery bypass surgery (TEG-CABG trial): assessing and monitoring the antithrombotic effect of clopidogrel and aspirin versus aspirin alone in hypercoagulable patients: study protocol for a randomized controlled trial

Sulman Rafiq — 2012-04-27T00:00:00Z

Background: Hypercoagulability, assessed by the thrombelastography (TEG) assay, has in several observational studies been associated with an increased risk of post-procedural thromboembolic complications. We hypothesize that intensified antiplatelet therapy with clopidogrel and aspirin, as compared to aspirin alone, will improve saphenous vein graft patency in preoperatively TEG-Hypercoagulable coronary artery bypass surgery (CABG) patients and reduce their risk for thromboembolic complications and death postoperatively. Methods: This is a prospective randomized clinical trial, with an open-label design with blinded evaluation of graft patency. TEG-Hypercoagulability is defined as a TEG maximum amplitude above 69 mm. Two hundred and fifty TEG-Hypercoagulable patients will be randomized to either an interventional group receiving clopidogrel 75 mg daily for three months (after initial oral bolus of 300 mg) together with aspirin 75 mg or a control group receiving aspirin 75 mg daily alone. Monitoring of antiplatelet efficacy and on-treatment platelet reactivity to clopidogrel and aspirin will be conducted with Multiplate aggregometry. Graft patency will be assessed with Multislice computed tomography (MSCT) at three months after surgery. Conclusions: The present trial is the first randomized clinical trial to evaluate whether TEG-Hypercoagulable CABG patients will benefit from intensified antiplatelet therapy after surgery. Monitoring of platelet inhibition from instituted antithrombotic therapy will elucidate platelet resistance patterns after CABG surgery. The results could be helpful in redefining how clinicians can evaluate patients preoperatively for their postoperative thromboembolic risk and tailor individualized postoperative antiplatelet therapy.Trial registrationClinicaltrials.gov Identifier NCT01046942

Comparing the effect of hydroxyethyl starch 130/0.4 with balanced crystalloid solution on mortality and kidney failure in patients with severe sepsis (6S - Scandinavian Starch for Severe Sepsis/Septic Shock trial): Study protocol, design and rationale for a double-blinded, randomised clinical trial

Anders Perner — 2011-01-27T00:00:00Z

Background: By tradition colloid solutions have been used to obtain fast circulatory stabilisation in shock, but high molecular weight hydroxyethyl starch (HES) may cause acute kidney failure in patients with severe sepsis. Now lower molecular weight HES 130/0.4 is the preferred colloid in Scandinavian intensive care units (ICUs) and 1st choice fluid for patients with severe sepsis. However, HES 130/0.4 is largely unstudied in patients with severe sepsis.Methods/DesignThe 6S trial will randomise 800 patients with severe sepsis in 30 Scandinavian ICUs to masked fluid resuscitation using either 6% HES 130/0.4 in Ringer's acetate or Ringer's acetate alone. The composite endpoint of 90-day mortality or end-stage kidney failure is the primary outcome measure. The secondary outcome measures are severe bleeding or allergic reactions, organ failure, acute kidney failure, days alive without renal replacement therapy or ventilator support and 28-day and 1/2- and one-year mortality. The sample size will allow the detection of a 10% absolute difference between the two groups in the composite endpoint with a power of 80%.DiscussionThe 6S trial will provide important safety and efficacy data on the use of HES 130/0.4 in patients with severe sepsis. The effects on mortality, dialysis-dependency, time on ventilator, bleeding and markers of resuscitation, metabolism, kidney failure, and coagulation will be assessed.Trial RegistrationClinicalTrials.gov: NCT00962156

Design, analysis, and presentation of crossover trials

Edward Mills — 2009-04-30T00:00:00Z

ObjectiveAlthough crossover trials enjoy wide use, standards for analysis and reporting have not been established. We reviewed methodological aspects and quality of reporting in a representative sample of published crossover trials. Methods: We searched MEDLINE for December 2000 and identified all randomized crossover trials. We abstracted data independently, in duplicate, on 14 design criteria, 13 analysis criteria, and 14 criteria assessing the data presentation. Results: We identified 526 randomized controlled trials, of which 116 were crossover trials. Trials were drug efficacy (48%), pharmacokinetic (28%), and nonpharmacologic (30%). The median sample size was 15 (interquartile range 8–38). Most (72%) trials used 2 treatments and had 2 periods (64%). Few trials reported allocation concealment (17%) or sequence generation (7%). Only 20% of trials reported a sample size calculation and only 31% of these considered pairing of data in the calculation. Carry-over issues were addressed in 29% of trial's methods. Most trials reported and defended a washout period (70%). Almost all trials (93%) tested for treatment effects using paired data and also presented details on by-group results (95%). Only 29% presented CIs or SE so that data could be entered into a meta-analysis. Conclusion: Reports of crossover trials frequently omit important methodological issues in design, analysis, and presentation. Guidelines for the conduct and reporting of crossover trials might improve the conduct and reporting of studies using this important trial design.