Toye, Francine; Williamson, Esther; Williams, Mark A; Fairbank, Jeremy; Lamb, Sarah E
2016-08-09
Using an example of qualitative research embedded in a non-surgical feasibility trial, we explore the benefits of including qualitative research in trial design and reflect on epistemological challenges. We interviewed 18 trial participants and used methods of Interpretive Phenomenological Analysis. Our findings demonstrate that qualitative research can make a valuable contribution by allowing trial stakeholders to see things from alternative perspectives. Specifically, it can help to make specific recommendations for improved trial design, generate questions which contextualize findings, and also explore disease experience beyond the trial. To make the most out of qualitative research embedded in quantitative design it would be useful to (a) agree specific qualitative study aims that underpin research design, (b) understand the impact of differences in epistemological truth claims, (c) provide clear thematic interpretations for trial researchers to utilize, and (d) include qualitative findings that explore experience beyond the trial setting within the impact plan. © The Author(s) 2016.
76 FR 22404 - Analgesic Clinical Trials Innovation, Opportunities, and Networks (ACTION) Initiative
Federal Register 2010, 2011, 2012, 2013, 2014
2011-04-21
..., but not limited to, specific research designs and methodological features so as to inform the future... clinical trials. Many experts in analgesic drug development believe that it is the design of the clinical trials that is at fault in this situation and that better trial designs will yield more successful...
Clinical Trials of Precision Medicine through Molecular Profiling: Focus on Breast Cancer.
Zardavas, Dimitrios; Piccart-Gebhart, Martine
2015-01-01
High-throughput technologies of molecular profiling in cancer, such as gene-expression profiling and next-generation sequencing, are expanding our knowledge of the molecular landscapes of several cancer types. This increasing knowledge coupled with the development of several molecularly targeted agents hold the promise for personalized cancer medicine to be fully realized. Moreover, an expanding armamentarium of targeted agents has been approved for the treatment of specific molecular cancer subgroups in different diagnoses. According to this paradigm, treatment selection should be dictated by the specific molecular aberrations found in each patient's tumor. The classical clinical trials paradigm of patients' eligibility being based on clinicopathologic parameters is being abandoned, with current clinical trials enrolling patients on the basis of specific molecular aberrations. New, innovative trial designs have been generated to better tackle the multiple challenges induced by the increasing molecular fragmentation of cancer, namely: (1) longitudinal cohort studies with or without downstream trials, (2) studies assessing the clinical utility of molecular profiling, (3) master or umbrella trials, (4) basket trials, (5) N-of-1 trials, and (6) adaptive design trials. This article provides an overview of the challenges for clinical trials in the era of molecular profiling of cancer. Subsequently, innovative trial designs with respective examples and their potential to expedite efficient clinical development of targeted anticancer agents is discussed.
ERIC Educational Resources Information Center
McGuire, Patricia, Ed.; O'Brien, Edward L.; Arbetman, Lee; Mills, Vivian H.; Pannell, Andrew
Designed to facilitate the expanded use of mock trials, this manual is divided into two principle sections--a teacher's guide and a student's guide. The teacher's guide contains specific advice to teachers on all aspects of preparing for a mock trial and seven specific lesson plans for a 2- to 3-week mock trial unit. Each lesson contains…
Haresnape, Claire
2013-01-01
Placebo appears to be a real neurobiological phenomenon that has evolved through the selection pressure to be able to heal ourselves. The complex language and social structures of humans means that we can attribute meaning to therapeutic encounters with culturally sanctioned authority figures and we can use our attachment to such figures to generate hope for recovery. Different mechanisms may be involved in the neurobiological aspect of placebo including anxiety, learning, conditioning as well as individual genetic variation. Examination of the published work shows that while some trials do seem to indicate a specific mode of action for homeopathic remedies other trials do not and this is an issue that needs to be addressed at the trial design stage. A clinical trial that includes both a placebo group and a non-participating control arm is the most powerful design for separating the non-specific and polymorphic placebo effect from the specific effects of trial medication. The control variables in a trial of homeopathic medication should also include the process of consultation as this may assume a meaning for the individual that can also be associated with a placebo effect. PMID:24040505
Directions for new developments on statistical design and analysis of small population group trials.
Hilgers, Ralf-Dieter; Roes, Kit; Stallard, Nigel
2016-06-14
Most statistical design and analysis methods for clinical trials have been developed and evaluated where at least several hundreds of patients could be recruited. These methods may not be suitable to evaluate therapies if the sample size is unavoidably small, which is usually termed by small populations. The specific sample size cut off, where the standard methods fail, needs to be investigated. In this paper, the authors present their view on new developments for design and analysis of clinical trials in small population groups, where conventional statistical methods may be inappropriate, e.g., because of lack of power or poor adherence to asymptotic approximations due to sample size restrictions. Following the EMA/CHMP guideline on clinical trials in small populations, we consider directions for new developments in the area of statistical methodology for design and analysis of small population clinical trials. We relate the findings to the research activities of three projects, Asterix, IDeAl, and InSPiRe, which have received funding since 2013 within the FP7-HEALTH-2013-INNOVATION-1 framework of the EU. As not all aspects of the wide research area of small population clinical trials can be addressed, we focus on areas where we feel advances are needed and feasible. The general framework of the EMA/CHMP guideline on small population clinical trials stimulates a number of research areas. These serve as the basis for the three projects, Asterix, IDeAl, and InSPiRe, which use various approaches to develop new statistical methodology for design and analysis of small population clinical trials. Small population clinical trials refer to trials with a limited number of patients. Small populations may result form rare diseases or specific subtypes of more common diseases. New statistical methodology needs to be tailored to these specific situations. The main results from the three projects will constitute a useful toolbox for improved design and analysis of small population clinical trials. They address various challenges presented by the EMA/CHMP guideline as well as recent discussions about extrapolation. There is a need for involvement of the patients' perspective in the planning and conduct of small population clinical trials for a successful therapy evaluation.
75 FR 34997 - National Institute on Disability and Rehabilitation Research (NIDRR)-Disability and...
Federal Register 2010, 2011, 2012, 2013, 2014
2010-06-21
... trial research designs to evaluate the effectiveness of interventions or practices. NIDRR believes that randomized control trial research designs can be appropriate for research that involves evaluating specific interventions. However, in complex service delivery settings, other scientifically rigorous research designs may...
Design of control-group conditions in clinical trials of behavioral interventions.
Lindquist, Ruth; Wyman, Jean F; Talley, Kristine M C; Findorff, Mary J; Gross, Cynthia R
2007-01-01
To review considerations in the design of placebo (attention) control conditions for community-based clinical trials of health behavior change interventions and to provide practical strategies for the design of control conditions. A well-designed control condition is an essential component of a clinical trial to foster the unambiguous interpretation of study findings. Pitfalls in the design of control conditions in clinical trials of behavioral interventions are identified and strategies to address them are offered. Types of control conditions that have been used in fall prevention trials are described, along with their strengths and weaknesses. The control condition used in the recent fall evaluation and prevention program (FEPP) was designed to overcome limitations of previous trial designs; it is provided to illustrate how to apply specific design principles. Pitfalls in the design of behavioral intervention studies may be avoided with the application of sound design principles. The FEPP active control condition can be used as a model in the design of future studies.
An electronic regulatory document management system for a clinical trial network.
Zhao, Wenle; Durkalski, Valerie; Pauls, Keith; Dillon, Catherine; Kim, Jaemyung; Kolk, Deneil; Silbergleit, Robert; Stevenson, Valerie; Palesch, Yuko
2010-01-01
A computerized regulatory document management system has been developed as a module in a comprehensive Clinical Trial Management System (CTMS) designed for an NIH-funded clinical trial network in order to more efficiently manage and track regulatory compliance. Within the network, several institutions and investigators are involved in multiple trials, and each trial has regulatory document requirements. Some of these documents are trial specific while others apply across multiple trials. The latter causes a possible redundancy in document collection and management. To address these and other related challenges, a central regulatory document management system was designed. This manuscript shares the design of the system as well as examples of it use in current studies. Copyright (c) 2009 Elsevier Inc. All rights reserved.
Using simulation to aid trial design: Ring-vaccination trials.
Hitchings, Matt David Thomas; Grais, Rebecca Freeman; Lipsitch, Marc
2017-03-01
The 2014-6 West African Ebola epidemic highlights the need for rigorous, rapid clinical trial methods for vaccines. A challenge for trial design is making sample size calculations based on incidence within the trial, total vaccine effect, and intracluster correlation, when these parameters are uncertain in the presence of indirect effects of vaccination. We present a stochastic, compartmental model for a ring vaccination trial. After identification of an index case, a ring of contacts is recruited and either vaccinated immediately or after 21 days. The primary outcome of the trial is total vaccine effect, counting cases only from a pre-specified window in which the immediate arm is assumed to be fully protected and the delayed arm is not protected. Simulation results are used to calculate necessary sample size and estimated vaccine effect. Under baseline assumptions about vaccine properties, monthly incidence in unvaccinated rings and trial design, a standard sample-size calculation neglecting dynamic effects estimated that 7,100 participants would be needed to achieve 80% power to detect a difference in attack rate between arms, while incorporating dynamic considerations in the model increased the estimate to 8,900. This approach replaces assumptions about parameters at the ring level with assumptions about disease dynamics and vaccine characteristics at the individual level, so within this framework we were able to describe the sensitivity of the trial power and estimated effect to various parameters. We found that both of these quantities are sensitive to properties of the vaccine, to setting-specific parameters over which investigators have little control, and to parameters that are determined by the study design. Incorporating simulation into the trial design process can improve robustness of sample size calculations. For this specific trial design, vaccine effectiveness depends on properties of the ring vaccination design and on the measurement window, as well as the epidemiologic setting.
2010-01-01
Background Manual Therapy applied to patients with non specific neck pain has been investigated several times. In the Netherlands, manual therapy as applied according to the Utrecht School of Manual Therapy (MTU) has not been the subject of a randomized controlled trial. MTU differs in diagnoses and treatment from other forms of manual therapy. Methods/Design This is a single blind randomized controlled trial in patients with sub-acute and chronic non specific neck pain. Patients with neck complaints existing for two weeks (minimum) till one year (maximum) will participate in the trial. 180 participants will be recruited in thirteen primary health care centres in the Netherlands. The experimental group will be treated with MTU during a six week period. The control group will be treated with physical therapy (standard care, mainly active exercise therapy), also for a period of six weeks. Primary outcomes are Global Perceived Effect (GPE) and functional status (Neck Disability Index (NDI-DV)). Secondary outcomes are neck pain (Numeric Rating Scale (NRS)), Eurocol, costs and quality of life (SF36). Discussion This paper presents details on the rationale of MTU, design, methods and operational aspects of the trial. Trial registration ClinicalTrials.gov Identifier: NCT00713843 PMID:20096136
Dose-finding designs for trials of molecularly targeted agents and immunotherapies
Chiuzan, Cody; Shtaynberger, Jonathan; Manji, Gulam A.; Duong, Jimmy K.; Schwartz, Gary K.; Ivanova, Anastasia; Lee, Shing M.
2017-01-01
Recently, there has been a surge of early phase trials of molecularly targeted agents (MTAs) and immunotherapies. These new therapies have different toxicity profiles compared to cytotoxic therapies. MTAs can benefit from new trial designs that allow inclusion of low-grade toxicities, late-onset toxicities, addition of an efficacy endpoint, and flexibility in the specification of a target toxicity probability. To study the degree of adoption of these methods, we conducted a Web of Science search of articles published between 2008 and 2014 that describe phase 1 oncology trials. Trials were categorized based on the dose-finding design used and the type of drug studied. Out of 1,712 dose-finding trials that met our criteria, 1,591 (92.9%) utilized a rule-based design, and 92 (5.4%; range 2.3% in 2009 to 9.7% in 2014) utilized a model-based or novel design. Over half of the trials tested an MTA or immunotherapy. Among the MTA and immunotherapy trials, 5.8% used model-based methods, compared to 3.9% and 8.3% of the chemotherapy or radiotherapy trials, respectively. While the percentage of trials using novel dose-finding designs has tripled since 2007, only 7.1% of trials use novel designs. PMID:28166468
Merle, Corinne S C; Sismanidis, Charalambos; Sow, Oumou Bah; Gninafon, Martin; Horton, John; Lapujade, Olivier; Lo, Mame Bocar; Mitchinson, Denis A; Perronne, Christian; Portaels, Francoise; Odhiambo, Joseph; Olliaro, Piero; Rustomjee, Roxana; Lienhardt, Christian; Fielding, Katherine
2012-05-18
There have been no major advances in tuberculosis (TB) drug development since the first East African/British Medical Research Council short course chemotherapy trial 35 years ago. Since then, the landscape for conducting TB clinical trials has profoundly changed with the emergence of HIV infection, the spread of resistant TB bacilli strains, recent advances in mycobacteriological capacity, and drug discovery. As a consequence questions have arisen on the most appropriate approach to design and conduct current TB trials. To highlight key issues discussed: Is a superiority, equivalence, or non-inferiority design most appropriate? What should be the primary efficacy outcome? How to consider re-infections in the definition of the outcome? What is the optimal length of patient follow-up? Is blinding appropriate when treatment duration in test arm is shorter? What are the appropriate assumptions for sample size calculation? Various drugs are currently in the development pipeline. We are presenting in this paper the design of the most recently completed phase III TB trial, the OFLOTUB project, which is the pivotal trial of a registration portfolio for a gatifloxacin-containing TB regimen. It is a randomized, open-label, multicenter, controlled trial aiming to evaluate the efficacy and safety of a gatifloxacin-containing 4-month regimen (trial registration: ClinicalTrial.gov database: NCT00216385). In the light of the recent scientific and regulatory discussions, we discuss some of the design issues in TB clinical trials and more specifically the reasons that guided our choices, in order to best answer the trial objectives, while at the same time satisfying regulatory authority requirements. When shortening TB treatment, we are advocating for a non-inferiority, non-blinded design, with a composite unfavorable endpoint assessed 12 months post treatment completion, and added trial procedures specifically aiming to: (1) minimize endpoint unavailability; and (2) distinguish between relapse and re-infection.
2012-01-01
Background There have been no major advances in tuberculosis (TB) drug development since the first East African/British Medical Research Council short course chemotherapy trial 35 years ago. Since then, the landscape for conducting TB clinical trials has profoundly changed with the emergence of HIV infection, the spread of resistant TB bacilli strains, recent advances in mycobacteriological capacity, and drug discovery. As a consequence questions have arisen on the most appropriate approach to design and conduct current TB trials. To highlight key issues discussed: Is a superiority, equivalence, or non-inferiority design most appropriate? What should be the primary efficacy outcome? How to consider re-infections in the definition of the outcome? What is the optimal length of patient follow-up? Is blinding appropriate when treatment duration in test arm is shorter? What are the appropriate assumptions for sample size calculation? Methods Various drugs are currently in the development pipeline. We are presenting in this paper the design of the most recently completed phase III TB trial, the OFLOTUB project, which is the pivotal trial of a registration portfolio for a gatifloxacin-containing TB regimen. It is a randomized, open-label, multicenter, controlled trial aiming to evaluate the efficacy and safety of a gatifloxacin-containing 4-month regimen (trial registration: ClinicalTrial.gov database: NCT00216385). Results In the light of the recent scientific and regulatory discussions, we discuss some of the design issues in TB clinical trials and more specifically the reasons that guided our choices, in order to best answer the trial objectives, while at the same time satisfying regulatory authority requirements. Conclusion When shortening TB treatment, we are advocating for a non-inferiority, non-blinded design, with a composite unfavorable endpoint assessed 12 months post treatment completion, and added trial procedures specifically aiming to: (1) minimize endpoint unavailability; and (2) distinguish between relapse and re-infection. PMID:22607233
Paradigms for adaptive statistical information designs: practical experiences and strategies.
Wang, Sue-Jane; Hung, H M James; O'Neill, Robert
2012-11-10
In the last decade or so, interest in adaptive design clinical trials has gradually been directed towards their use in regulatory submissions by pharmaceutical drug sponsors to evaluate investigational new drugs. Methodological advances of adaptive designs are abundant in the statistical literature since the 1970s. The adaptive design paradigm has been enthusiastically perceived to increase the efficiency and to be more cost-effective than the fixed design paradigm for drug development. Much interest in adaptive designs is in those studies with two-stages, where stage 1 is exploratory and stage 2 depends upon stage 1 results, but where the data of both stages will be combined to yield statistical evidence for use as that of a pivotal registration trial. It was not until the recent release of the US Food and Drug Administration Draft Guidance for Industry on Adaptive Design Clinical Trials for Drugs and Biologics (2010) that the boundaries of flexibility for adaptive designs were specifically considered for regulatory purposes, including what are exploratory goals, and what are the goals of adequate and well-controlled (A&WC) trials (2002). The guidance carefully described these distinctions in an attempt to minimize the confusion between the goals of preliminary learning phases of drug development, which are inherently substantially uncertain, and the definitive inference-based phases of drug development. In this paper, in addition to discussing some aspects of adaptive designs in a confirmatory study setting, we underscore the value of adaptive designs when used in exploratory trials to improve planning of subsequent A&WC trials. One type of adaptation that is receiving attention is the re-estimation of the sample size during the course of the trial. We refer to this type of adaptation as an adaptive statistical information design. Specifically, a case example is used to illustrate how challenging it is to plan a confirmatory adaptive statistical information design. We highlight the substantial risk of planning the sample size for confirmatory trials when information is very uninformative and stipulate the advantages of adaptive statistical information designs for planning exploratory trials. Practical experiences and strategies as lessons learned from more recent adaptive design proposals will be discussed to pinpoint the improved utilities of adaptive design clinical trials and their potential to increase the chance of a successful drug development. Published 2012. This article is a US Government work and is in the public domain in the USA.
Cunanan, Kristen M; Carlin, Bradley P; Peterson, Kevin A
2016-12-01
Many clinical trial designs are impractical for community-based clinical intervention trials. Stepped wedge trial designs provide practical advantages, but few descriptions exist of their clinical implementational features, statistical design efficiencies, and limitations. Enhance efficiency of stepped wedge trial designs by evaluating the impact of design characteristics on statistical power for the British Columbia Telehealth Trial. The British Columbia Telehealth Trial is a community-based, cluster-randomized, controlled clinical trial in rural and urban British Columbia. To determine the effect of an Internet-based telehealth intervention on healthcare utilization, 1000 subjects with an existing diagnosis of congestive heart failure or type 2 diabetes will be enrolled from 50 clinical practices. Hospital utilization is measured using a composite of disease-specific hospital admissions and emergency visits. The intervention comprises online telehealth data collection and counseling provided to support a disease-specific action plan developed by the primary care provider. The planned intervention is sequentially introduced across all participating practices. We adopt a fully Bayesian, Markov chain Monte Carlo-driven statistical approach, wherein we use simulation to determine the effect of cluster size, sample size, and crossover interval choice on type I error and power to evaluate differences in hospital utilization. For our Bayesian stepped wedge trial design, simulations suggest moderate decreases in power when crossover intervals from control to intervention are reduced from every 3 to 2 weeks, and dramatic decreases in power as the numbers of clusters decrease. Power and type I error performance were not notably affected by the addition of nonzero cluster effects or a temporal trend in hospitalization intensity. Stepped wedge trial designs that intervene in small clusters across longer periods can provide enhanced power to evaluate comparative effectiveness, while offering practical implementation advantages in geographic stratification, temporal change, use of existing data, and resource distribution. Current population estimates were used; however, models may not reflect actual event rates during the trial. In addition, temporal or spatial heterogeneity can bias treatment effect estimates. © The Author(s) 2016.
Ethical considerations of neuro-oncology trial design in the era of precision medicine.
Gupta, Saksham; Smith, Timothy R; Broekman, Marike L
2017-08-01
The field of oncology is currently undergoing a paradigm shift. Advances in the understanding of tumor biology and in tumor sequencing technology have contributed to the shift towards precision medicine, the therapeutic framework of targeting the individual oncogenic changes each tumor harbors. The success of precision medicine therapies, such as targeted kinase inhibitors and immunotherapies, in other cancers have motivated studies in brain cancers. The high specificity and cost of these therapies also encourage a shift in clinical trial design away from randomized control trials towards smaller, more exclusive early phase clinical trials. While these new trials advance the clinical application of increasingly precise and individualized therapies, their design brings ethical challenges . We review the pertinent ethical considerations for clinical trials of precision medicine in neuro-oncology and discuss methods to protect patients in this new era of trial design.
Wason, James M. S.; Mander, Adrian P.
2012-01-01
Two-stage designs are commonly used for Phase II trials. Optimal two-stage designs have the lowest expected sample size for a specific treatment effect, for example, the null value, but can perform poorly if the true treatment effect differs. Here we introduce a design for continuous treatment responses that minimizes the maximum expected sample size across all possible treatment effects. The proposed design performs well for a wider range of treatment effects and so is useful for Phase II trials. We compare the design to a previously used optimal design and show it has superior expected sample size properties. PMID:22651118
External validity of randomized controlled trials in older adults, a systematic review.
van Deudekom, Floor J; Postmus, Iris; van der Ham, Danielle J; Pothof, Alexander B; Broekhuizen, Karen; Blauw, Gerard J; Mooijaart, Simon P
2017-01-01
To critically assess the external validity of randomized controlled trials (RCTs) it is important to know what older adults have been enrolled in the trials. The aim of this systematic review is to study what proportion of trials specifically designed for older patients report on somatic status, physical and mental functioning, social environment and frailty in the patient characteristics. PubMed was searched for articles published in 2012 and only RCTs were included. Articles were further excluded if not conducted with humans or only secondary analyses were reported. A random sample of 10% was drawn. The current review analyzed this random sample and further selected trials when the reported mean age was ≥ 60 years. We extracted geriatric assessments from the population descriptives or the in- and exclusion criteria. In total 1396 trials were analyzed and 300 trials included. The median of the reported mean age was 66 (IQR 63-70) and the median percentage of men in the trials was 60 (IQR 45-72). In 34% of the RCTs specifically designed for older patients somatic status, physical and mental functioning, social environment or frailty were reported in the population descriptives or the in- and exclusion criteria. Physical and mental functioning was reported most frequently (22% and 14%). When selecting RCTs on a mean age of 70 or 80 years the report of geriatric assessments in the patient characteristics was 46% and 85% respectively but represent only 5% and 1% of the trials. Somatic status, physical and mental functioning, social environment and frailty are underreported even in RCTs specifically designed for older patients published in 2012. Therefore, it is unclear for clinicians to which older patients the results can be applied. We recommend systematic to transparently report these relevant characteristics of older participants included in RCTs.
Jiang, Wei; Mahnken, Jonathan D; He, Jianghua; Mayo, Matthew S
2016-11-01
For two-arm randomized phase II clinical trials, previous literature proposed an optimal design that minimizes the total sample sizes subject to multiple constraints on the standard errors of the estimated event rates and their difference. The original design is limited to trials with dichotomous endpoints. This paper extends the original approach to be applicable to phase II clinical trials with endpoints from the exponential dispersion family distributions. The proposed optimal design minimizes the total sample sizes needed to provide estimates of population means of both arms and their difference with pre-specified precision. Its applications on data from specific distribution families are discussed under multiple design considerations. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.
Drug-device trials for infectious diseases: CDRH perspective.
Meier, Kristen L; Gitterman, Steven
2011-05-01
Assessing the performance of new diagnostic tests for infectious diseases has traditionally focused on comparing the new assay against a reference standard such as culture. In this paper, we suggest that clinical trial designs with both a diagnostic and therapeutic component may be necessary to evaluate the safety and effectiveness of nonmicrobiologically based assays, with a specific emphasis on the test/marker-stratified design. General design challenges for trials of infectious diseases that simultaneously study both diagnostic and therapeutic components (eg, both devices and drugs) are also discussed.
Redirecting T-cell specificity by introducing a tumor-specific chimeric antigen receptor
Jena, Bipulendu; Dotti, Gianpietro
2010-01-01
Infusions of antigen-specific T cells have yielded therapeutic responses in patients with pathogens and tumors. To broaden the clinical application of adoptive immunotherapy against malignancies, investigators have developed robust systems for the genetic modification and characterization of T cells expressing introduced chimeric antigen receptors (CARs) to redirect specificity. Human trials are under way in patients with aggressive malignancies to test the hypothesis that manipulating the recipient and reprogramming T cells before adoptive transfer may improve their therapeutic effect. These examples of personalized medicine infuse T cells designed to meet patients' needs by redirecting their specificity to target molecular determinants on the underlying malignancy. The generation of clinical grade CAR+ T cells is an example of bench-to-bedside translational science that has been accomplished using investigator-initiated trials operating largely without industry support. The next-generation trials will deliver designer T cells with improved homing, CAR-mediated signaling, and replicative potential, as investigators move from the bedside to the bench and back again. PMID:20439624
Towards evidence-based medicine in specific grass pollen immunotherapy.
Calderon, M; Mösges, R; Hellmich, M; Demoly, P
2010-04-01
When initiating grass pollen immunotherapy for seasonal allergic rhinoconjunctivitis, specialist physicians in many European countries must choose between modalities of differing pharmaceutical and regulatory status. We applied an evidence-based medicine (EBM) approach to commercially available subcutaneous and sublingual Gramineae grass pollen immunotherapies (SCIT and SLIT) by evaluating study design, populations, pollen seasons, treatment doses and durations, efficacy, quality of life, safety and compliance. After searching MEDLINE, Embase and the Cochrane Library up until January 2009, we identified 33 randomized, double-blind, placebo-controlled trials (including seven paediatric trials) with a total of 440 specific immunotherapy (SIT)-treated subjects in seven trials (0 paediatric) for SCIT with natural pollen extracts, 168 in three trials (0 paediatric) for SCIT with allergoids, 906 in 16 trials (five paediatric) for natural extract SLIT drops, 41 in two trials (one paediatric) for allergoid SLIT tablets and 1605 in five trials (two paediatric) for natural extract SLIT tablets. Trial design and quality varied significantly within and between SIT modalities. The multinational, rigorous trials of natural extract SLIT tablets correspond to a high level of evidence in adult and paediatric populations. The limited amount of published data on allergoids prevented us from judging the level of evidence for this modality.
Seymour, Lesley; Ivy, S. Percy; Sargent, Daniel; Spriggs, David; Baker, Laurence; Rubinstein, Larry; Ratain, Mark J; Le Blanc, Michael; Stewart, David; Crowley, John; Groshen, Susan; Humphrey, Jeffrey S; West, Pamela; Berry, Donald
2010-01-01
The optimal design of phase II studies continues to be the subject of vigorous debate, especially with regards to studies of newer molecularly targeted agents. The observations that many new therapeutics ‘fail’ in definitive phase III studies, coupled with the numbers of new agents to be tested as well as the increasing costs and complexity of clinical trials further emphasizes the critical importance of robust and efficient phase II design. The Clinical Trial Design Task Force(CTD-TF)of the NCI Investigational Drug Steering Committee (IDSC) has published a series of discussion papers on Phase II trial design in Clinical Cancer Research. The IDSC has developed formal recommendations regarding aspects of phase II trial design which are the subject of frequent debate such as endpoints(response vs. progression free survival), randomization(single arm designs vs. randomization), inclusion of biomarkers, biomarker based patient enrichment strategies, and statistical design(e.g. two stage designs vs. multiple-group adaptive designs). While these recommendations in general encourage the use of progression-free survival as the primary endpoint, the use of randomization, the inclusion of biomarkers and the incorporation of newer designs, we acknowledge that objective response as an endpoint, and single arm designs, remain relevant in certain situations. The design of any clinical trial should always be carefully evaluated and justified based on the characteristic specific to the situation. PMID:20215557
The Use of Cannabis for Headache Disorders
Lochte, Bryson C.; Beletsky, Alexander; Samuel, Nebiyou K.; Grant, Igor
2017-01-01
Abstract Headache disorders are common, debilitating, and, in many cases, inadequately managed by existing treatments. Although clinical trials of cannabis for neuropathic pain have shown promising results, there has been limited research on its use, specifically for headache disorders. This review considers historical prescription practices, summarizes the existing reports on the use of cannabis for headache, and examines the preclinical literature exploring the role of exogenous and endogenous cannabinoids to alter headache pathophysiology. Currently, there is not enough evidence from well-designed clinical trials to support the use of cannabis for headache, but there are sufficient anecdotal and preliminary results, as well as plausible neurobiological mechanisms, to warrant properly designed clinical trials. Such trials are needed to determine short- and long-term efficacy for specific headache types, compatibility with existing treatments, optimal administration practices, as well as potential risks. PMID:28861505
Specifications of a continual reassessment method design for phase I trials of combined drugs†
Wages, Nolan A.; Conaway, Mark R.
2013-01-01
In studies of combinations of agents in phase I oncology trials, the dose–toxicity relationship may not be monotone for all combinations, in which case the toxicity probabilities follow a partial order. The continual reassessment method for partial orders (PO-CRM) is a design for phase I trials of combinations that leans upon identifying possible complete orders associated with the partial order. This article addresses some practical design considerations not previously undertaken when describing the PO-CRM. We describe an approach in choosing a proper subset of possible orderings, formulated according to the known toxicity relationships within a matrix of combination therapies. Other design issues, such as working model selection and stopping rules, are also discussed. We demonstrate the practical ability of PO-CRM as a phase I design for combinations through its use in a recent trial designed at the University of Virginia Cancer Center. PMID:23729323
Comparison of study designs for acute otitis media trials.
Pichichero, Michael E; Casey, Janet R
2008-06-01
A framework for evaluating the efficacy of antibiotics in development as well as those currently approved for acute otitis media (AOM) is needed. Review strengths and limitations of various antibiotic trial designs and their outcome measures. A review of 157 published trials involving 36,710 subjects for the treatment of AOM. AOM trials have three designs: (1) clinical, clinical diagnosis and assessment of outcomes; (2) single tympanocentesis, microbiologic diagnosis (by middle ear fluid culture) and clinical assessment of outcomes; and (3) double tympanocentesis, microbiologic diagnosis and microbiologic outcome assessment. Identifiable strengths and limitations of each design are reviewed. Case definitions for entry of children in trials of AOM vary widely. The lack of stringent diagnostic criteria in a clinical design allows for inclusion of a significant proportion of children with a non-bacterial etiology (i.e., viral AOM or otitis media with effusion). Tympanocentesis increases diagnostic accuracy at study entry; however, the procedure is confounding because of its potentially therapeutic benefit and the procedure is not performed in a uniform manner. A second tympanocentesis allows a high sensitivity to detect microbiologic eradication, but it does not correlate with clinical outcomes in half of the cases. The timing of outcome assessment also varies widely among trials. Improved clinical diagnosis criteria for AOM are needed to enhance specificity; emphasis on a bulging tympanic membrane has the best evidence base. Tympanocentesis within study designs has merits. At study entry it assures diagnostic accuracy but may alter outcomes and it is useful to document microbiologic outcomes but lacks specificity for clinical outcomes. For all designs, test of cure assessment 2-7 days after completion of therapy seems most appropriate.
Challenges and opportunities in SLE clinical trials.
van Vollenhoven, Ronald F
2013-09-01
To provide an update on the field of clinical trials in systemic lupus erythematosus (SLE). This review will examine failed and successful clinical trials in SLE in order to draw lessons and determine the optimal ways forward. Over the past decade, many clinical trials in SLE met with limited success, but in the past 2 years several SLE clinical trials have been successful. The two large phase III randomized controlled trials (RCTs) of belimumab achieved their primary endpoints and resulted in food and drug administration and European medicines agency approval of the drug. Characteristics of these trials were, among other things, a very large number of patients (>800 each), compound clinical endpoints, and a flexible design with regards to concomitant medication use. Likewise, large randomized controlled trials with mycophenolate mofetil, although nominally unsuccessful, clearly demonstrated the clinical benefit of this drug in lupus nephritis. Posthoc analyses of several failed trials involving abatacept and rituximab revealed design elements and/or outcomes that might have changed the outcomes of these studies. Many smaller trials have also been reported, in some instances with surprisingly positive results. An improved understanding of specific design features in SLE clinical trials combined with robust outcomes will make it possible more effectively to design and conduct clinical trials in SLE.
A systematic review of the use of an expertise-based randomised controlled trial design.
Cook, Jonathan A; Elders, Andrew; Boachie, Charles; Bassinga, Ted; Fraser, Cynthia; Altman, Doug G; Boutron, Isabelle; Ramsay, Craig R; MacLennan, Graeme S
2015-05-30
Under a conventional two-arm randomised trial design, participants are allocated to an intervention and participating health professionals are expected to deliver both interventions. However, health professionals often have differing levels of expertise in a skill-based interventions such as surgery or psychotherapy. An expertise-based approach to trial design, where health professionals only deliver an intervention in which they have expertise, has been proposed as an alternative. The aim of this project was to systematically review the use of an expertise-based trial design in the medical literature. We carried out a comprehensive search of nine databases--AMED, BIOSIS, CENTRAL, CINAHL, Cochrane Methodology Register, EMBASE, MEDLINE, Science Citation Index, and PsycINFO--from 1966 to 2012 and performed citation searches using the ISI Citation Indexes and Scopus. Studies that used an expertise-based trial design were included. Two review authors independently screened the titles and abstracts and assessed full-text reports. Data were extracted and summarised on the study characteristics, general and expertise-specific study methodology, and conduct. In total, 7476 titles and abstracts were identified, leading to 43 included studies (54 articles). The vast majority (88%) used a pure expertise-based design; three (7%) adopted a hybrid design, and two (5%) used a design that was unclear. Most studies compared substantially different interventions (79%). In many cases, key information relating to the expertise-based design was absent; only 12 (28%) reported criteria for delivering both interventions. Most studies recruited the target sample size or very close to it (median of 101, interquartile range of 94 to 118), although the target was reported for only 40% of studies. The proportion of participants who received the allocated intervention was high (92%, interquartile range of 82 to 99%). While use of an expertise-based trial design is growing, it remains uncommon. Reporting of study methodology and, particularly, expertise-related methodology was poor. Empirical evidence provided some support for purported benefits such as high levels of recruitment and compliance with allocation. An expertise-based trial design should be considered but its value seems context-specific, particularly when interventions differ substantially or interventions are typically delivered by different health professionals.
Opal, Steven M; Dellinger, R Phillip; Vincent, Jean-Louis; Masur, Henry; Angus, Derek C
2014-07-01
The developmental pipeline for novel therapeutics to treat sepsis has diminished to a trickle compared to previous years of sepsis research. While enormous strides have been made in understanding the basic molecular mechanisms that underlie the pathophysiology of sepsis, a long list of novel agents have now been tested in clinical trials without a single immunomodulating therapy showing consistent benefit. The only antisepsis agent to successfully complete a phase III clinical trial was human recumbent activated protein C. This drug was taken off the market after a follow-up placebo-controlled trial (human recombinant activated Protein C Worldwide Evaluation of Severe Sepsis and septic Shock [PROWESS SHOCK]) failed to replicate the favorable results of the initial registration trial performed ten years earlier. We must critically reevaluate our basic approach to the preclinical and clinical evaluation of new sepsis therapies. We selected the major clinical studies that investigated interventional trials with novel therapies to treat sepsis over the last 30 years. Phase II and phase III trials investigating new treatments for sepsis and editorials and critiques of these studies. Selected manuscripts and clinical study reports were analyzed from sepsis trials. Specific shortcomings and potential pit falls in preclinical evaluation and clinical study design and analysis were reviewed and synthesized. After review and discussion, a series of 12 recommendations were generated with suggestions to guide future studies with new treatments for sepsis. We need to improve our ability to define appropriate molecular targets for preclinical development and develop better methods to determine the clinical value of novel sepsis agents. Clinical trials must have realistic sample sizes and meaningful endpoints. Biomarker-driven studies should be considered to categorize specific "at risk" populations most likely to benefit from a new treatment. Innovations in clinical trial design such as parallel crossover design, alternative endpoints, or adaptive trials should be pursued to improve the outlook for future interventional trials in sepsis.
Choice of design and outcomes in trials among children with moderate acute malnutrition.
Friis, Henrik; Michaelsen, Kim F; Wells, Jonathan C
2015-03-01
There is a need for trials on the effects of food aid products for children with moderate acute malnutrition, to identify how best to restore body tissues and function. The choice of control intervention is a major challenge, with both ethical and scientific implications. While randomized trials are needed, special designs, such as cluster-randomized, stepped-wedged or factorial designs may offer advantages. Anthropometry is widely used as the primary outcome in such trials, but anthropometric traits do not refer directly to specific organs, tissues, or functions. Thus, it is difficult to understand what components of health might be impacted by public health programs, or the underlying mechanisms whereby improved nutritional status might benefit short- and long-term health. Measurement of body composition, specific growth markers and functional outcomes may provide greater insight into the nature and implications of growth failure and recovery. There are now several methodologies suitable for application in infants and young children, e.g., measuring body composition with deuterium dilution, physical activity with accelerometers and linear growth with knemometers. To evaluate the generalizability of the findings from nutrition trials, it is important to collect data on baseline nutritional status.
Changing the Paradigm for the Treatment and Development of New Therapies for FSGS
Spino, Cathie; Jahnke, Jordan S.; Selewski, David T.; Massengill, Susan; Troost, Jonathan; Gipson, Debbie S.
2016-01-01
Focal segmental glomerulosclerosis (FSGS) is a renal pathology finding that represents a constellation of rare kidney diseases, which manifest as proteinuria, edema nephrotic syndrome, hypertension, and increased risk for kidney failure. Therapeutic options for FSGS are reviewed displaying the expected efficacy from 25 to 69% depending on specific therapy, patient characteristics, cost, and common side effects. This variability in treatment response is likely caused, in part, by the heterogeneity in the etiology and active molecular mechanisms of FSGS. Clinical trials in FSGS have been scant in number and slow to recruit, which may stem, in part, from reliance on classic clinical trial design paradigms. Traditional clinical trial designs based on the “learn and confirm” paradigm may not be appropriate for rare diseases, such as FSGS. Future drug development and testing will require novel approaches to trial designs that have the capacity to enrich study populations and adapt the trial in a planned way to gain efficiencies in trial completion timelines. A clinical trial simulation is provided that compares a classical and more modern design to determine the maximum tolerated dose in FSGS. PMID:27047908
USN/USMC Commander’s Quick Reference Legal Handbook
2015-01-01
compounds of designer drugs. [See references (a), (f), and (g).] Commanders shall obtain authorization for testing for synthetic drug compounds from...17 Pre-Trial Agreements 19 Post -Trial Review 21 Victim/Witness Issues 23 Section II: Administrative...advocate except in extraordinary circumstances. Only flag or general officers (and a very few specifically designated non-flag/general officers who are
Holm Hansen, Christian; Warner, Pamela; Parker, Richard A; Walker, Brian R; Critchley, Hilary Od; Weir, Christopher J
2017-12-01
It is often unclear what specific adaptive trial design features lead to an efficient design which is also feasible to implement. This article describes the preparatory simulation study for a Bayesian response-adaptive dose-finding trial design. Dexamethasone for Excessive Menstruation aims to assess the efficacy of Dexamethasone in reducing excessive menstrual bleeding and to determine the best dose for further study. To maximise learning about the dose response, patients receive placebo or an active dose with randomisation probabilities adapting based on evidence from patients already recruited. The dose-response relationship is estimated using a flexible Bayesian Normal Dynamic Linear Model. Several competing design options were considered including: number of doses, proportion assigned to placebo, adaptation criterion, and number and timing of adaptations. We performed a fractional factorial study using SAS software to simulate virtual trial data for candidate adaptive designs under a variety of scenarios and to invoke WinBUGS for Bayesian model estimation. We analysed the simulated trial results using Normal linear models to estimate the effects of each design feature on empirical type I error and statistical power. Our readily-implemented approach using widely available statistical software identified a final design which performed robustly across a range of potential trial scenarios.
Yildirim, Oktay; Gottwald, Matthias; Schüler, Peter; Michel, Martin C
2016-01-01
Drug development faces the double challenge of increasing costs and increasing pressure on pricing. To avoid that lack of perceived commercial perspective will leave existing medical needs unmet, pharmaceutical companies and many other stakeholders are discussing ways to improve the efficiency of drug Research and Development. Based on an international symposium organized by the Medical School of the University of Duisburg-Essen (Germany) and held in January 2016, we discuss the opportunities and challenges of three specific areas, i.e., public-private partnerships, adaptive designs and big data. Public-private partnerships come in many different forms with regard to scope, duration and type and number of participants. They range from project-specific collaborations to strategic alliances to large multi-party consortia. Each of them offers specific opportunities and faces distinct challenges. Among types of collaboration, investigator-initiated studies are becoming increasingly popular but have legal, ethical, and financial implications. Adaptive trial designs are also increasingly discussed. However, adaptive should not be used as euphemism for the repurposing of a failed trial; rather it requires carefully planning and specification before a trial starts. Adaptive licensing can be a counter-part of adaptive trial design. The use of Big Data is another opportunity to leverage existing information into knowledge useable for drug discovery and development. Respecting limitations of informed consent and privacy is a key challenge in the use of Big Data. Speakers and participants at the symposium were convinced that appropriate use of the above new options may indeed help to increase the efficiency of future drug development.
Yildirim, Oktay; Gottwald, Matthias; Schüler, Peter; Michel, Martin C.
2016-01-01
Drug development faces the double challenge of increasing costs and increasing pressure on pricing. To avoid that lack of perceived commercial perspective will leave existing medical needs unmet, pharmaceutical companies and many other stakeholders are discussing ways to improve the efficiency of drug Research and Development. Based on an international symposium organized by the Medical School of the University of Duisburg-Essen (Germany) and held in January 2016, we discuss the opportunities and challenges of three specific areas, i.e., public–private partnerships, adaptive designs and big data. Public–private partnerships come in many different forms with regard to scope, duration and type and number of participants. They range from project-specific collaborations to strategic alliances to large multi-party consortia. Each of them offers specific opportunities and faces distinct challenges. Among types of collaboration, investigator-initiated studies are becoming increasingly popular but have legal, ethical, and financial implications. Adaptive trial designs are also increasingly discussed. However, adaptive should not be used as euphemism for the repurposing of a failed trial; rather it requires carefully planning and specification before a trial starts. Adaptive licensing can be a counter-part of adaptive trial design. The use of Big Data is another opportunity to leverage existing information into knowledge useable for drug discovery and development. Respecting limitations of informed consent and privacy is a key challenge in the use of Big Data. Speakers and participants at the symposium were convinced that appropriate use of the above new options may indeed help to increase the efficiency of future drug development. PMID:27999543
Clinical trial designs incorporating predictive biomarkers☆
Renfro, Lindsay A.; Mallick, Himel; An, Ming-Wen; Sargent, Daniel J.; Mandrekar, Sumithra J.
2016-01-01
Development of oncologic therapies has traditionally been performed in a sequence of clinical trials intended to assess safety (phase I), preliminary efficacy (phase II), and improvement over the standard of care (phase III) in homogeneous (in terms of tumor type and disease stage) patient populations. As cancer has become increasingly understood on the molecular level, newer “targeted” drugs that inhibit specific cancer cell growth and survival mechanisms have increased the need for new clinical trial designs, wherein pertinent questions on the relationship between patient biomarkers and response to treatment can be answered. Herein, we review the clinical trial design literature from initial to more recently proposed designs for targeted agents or those treatments hypothesized to have enhanced effectiveness within patient subgroups (e.g., those with a certain biomarker value or who harbor a certain genetic tumor mutation). We also describe a number of real clinical trials where biomarker-based designs have been utilized, including a discussion of their respective advantages and challenges. As cancers become further categorized and/or reclassified according to individual patient and tumor features, we anticipate a continued need for novel trial designs to keep pace with the changing frontier of clinical cancer research. PMID:26827695
Spine device clinical trials: design and sponsorship.
Cher, Daniel J; Capobianco, Robyn A
2015-05-01
Multicenter prospective randomized clinical trials represent the best evidence to support the safety and effectiveness of medical devices. Industry sponsorship of multicenter clinical trials is purported to lead to bias. To determine what proportion of spine device-related trials are industry-sponsored and the effect of industry sponsorship on trial design. Analysis of data from a publicly available clinical trials database. Clinical trials of spine devices registered on ClinicalTrials.gov, a publicly accessible trial database, were evaluated in terms of design, number and location of study centers, and sample size. The relationship between trial design characteristics and study sponsorship was evaluated using logistic regression and general linear models. One thousand six hundred thrity-eight studies were retrieved from ClinicalTrials.gov using the search term "spine." Of the 367 trials that focused on spine surgery, 200 (54.5%) specifically studied devices for spine surgery and 167 (45.5%) focused on other issues related to spine surgery. Compared with nondevice trials, device trials were far more likely to be sponsored by the industry (74% vs. 22.2%, odds ratio (OR) 9.9 [95% confidence interval 6.1-16.3]). Industry-sponsored device trials were more likely multicenter (80% vs. 29%, OR 9.8 [4.8-21.1]) and had approximately four times as many participating study centers (p<.0001) and larger sample sizes. There were very few US-based multicenter randomized trials of spine devices not sponsored by the industry. Most device-related spine research is industry-sponsored. Multicenter trials are more likely to be industry-sponsored. These findings suggest that previously published studies showing larger effect sizes in industry-sponsored vs. nonindustry-sponsored studies may be biased as a result of failure to take into account the marked differences in design and purpose. Copyright © 2015 Elsevier Inc. All rights reserved.
Cihoric, Nikola; Tsikkinis, Alexandros; Minniti, Giuseppe; Lagerwaard, Frank J; Herrlinger, Ulrich; Mathier, Etienne; Soldatovic, Ivan; Jeremic, Branislav; Ghadjar, Pirus; Elicin, Olgun; Lössl, Kristina; Aebersold, Daniel M; Belka, Claus; Herrmann, Evelyn; Niyazi, Maximilian
2017-01-03
The records of 208.777 (100%) clinical trials registered at ClinicalTrials.gov were downloaded on the 19th of February 2016. Phase II and III trials including patients with glioblastoma were selected for further classification and analysis. Based on the disease settings, trials were classified into three groups: newly diagnosed glioblastoma, recurrent disease and trials with no differentiation according to disease setting. Furthermore, we categorized trials according to the experimental interventions, the primary sponsor, the source of financial support and trial design elements. Trends were evaluated using the autoregressive integrated moving average model. Two hundred sixteen (0.1%) trials were selected for further analysis. Academic centers (investigator initiated trials) were recorded as primary sponsors in 56.9% of trials, followed by industry 25.9%. Industry was the leading source of monetary support for the selected trials in 44.4%, followed by 25% of trials with primarily academic financial support. The number of newly initiated trials between 2005 and 2015 shows a positive trend, mainly through an increase in phase II trials, whereas phase III trials show a negative trend. The vast majority of trials evaluate forms of different systemic treatments (91.2%). In total, one hundred different molecular entities or biologicals were identified. Of those, 60% were involving drugs specifically designed for central nervous system malignancies. Trials that specifically address radiotherapy, surgery, imaging and other therapeutic or diagnostic methods appear to be rare. Current research in glioblastoma is mainly driven or sponsored by industry, academic medical oncologists and neuro-oncologists, with the majority of trials evaluating forms of systemic therapies. Few trials reach phase III. Imaging, radiation therapy and surgical procedures are underrepresented in current trials portfolios. Optimization in research portfolio for glioblastoma is needed.
NASA Astrophysics Data System (ADS)
Boski, Marcin; Paszke, Wojciech
2017-01-01
This paper deals with designing of iterative learning control schemes for uncertain systems with static nonlinearities. More specifically, the nonlinear part is supposed to be sector bounded and system matrices are assumed to range in the polytope of matrices. For systems with such nonlinearities and uncertainties the repetitive process setting is exploited to develop a linear matrix inequality based conditions for computing the feedback and feedforward (learning) controllers. These controllers guarantee acceptable dynamics along the trials and ensure convergence of the trial-to-trial error dynamics, respectively. Numerical examples illustrate the theoretical results and confirm effectiveness of the designed control scheme.
Ferry, M.; Coley, N.; Andrieu, S.; Bonhomme, C.; Caubere, J.P.; Cesari, M.; Gautry, J.; Garcia Sanchez, I.; Hugonot, L.; Mansuy, L.; Pahor, M.; Pariente, J.; Ritz, P.; Salva, A.; Sijben, J.; Wieggers, R.; Ythier-Moury, P.; Zaim, M.; Zetlaoui, J.; Vellas, B.
2015-01-01
Interventions are crucial as they offer simple and inexpensive public health solutions that will be useful over the long term use. A Task Force on designing trials of nutritional interventions to slow cognitive decline in older adults was held in Toulouse in September 2012. The aim of the Task Force was to bring together leading experts from academia, the food industry and regulatory agencies to determine the best trial designs that would enable us to reach our goal of maintaining or improving cognitive function in apparently healthy aging people. An associated challenge for this Task Force was to determine the type of trials required by the Public Food Agencies for assessing the impact of nutritional compounds in comparison to well established requirements for drug trials. Although the required quality of the study design, rationale and statistical analysis remains the same, the studies designed to show reduction of cognitive decline require a long duration and the objectives of this task force was to determine best design for these trials. Two specific needs were identified to support trials of nutritional interventions: 1- Risk- reduction strategies are needed to tackle the growing burden of cognitive decline that may lead to dementia, 2- Innovative study designs are needed to improve the quality of these studies. PMID:23933873
Recommendations for the Design and Analysis of Treatment Trials for Alcohol Use Disorders
Witkiewitz, Katie; Finney, John W.; Harris, Alex H.S; Kivlahan, Daniel R.; Kranzler, Henry R.
2015-01-01
Background Over the past 60 years the view that “alcoholism” is a disease for which the only acceptable goal of treatment is abstinence has given way to the recognition that alcohol use disorders (AUDs) occur on a continuum of severity, for which a variety of treatment options are appropriate. However, because the available treatments for AUDs are not effective for everyone, more research is needed to develop novel and more efficacious treatments to address the range of AUD severity in diverse populations. Here we offer recommendations for the design and analysis of alcohol treatment trials, with a specific focus on the careful conduct of randomized clinical trials of medications and non-pharmacological interventions for AUDs. Methods Narrative review of the quality of published clinical trials and recommendations for the optimal design and analysis of treatment trials for AUDs. Results Despite considerable improvements in the design of alcohol clinical trials over the past two decades, many studies of AUD treatments have used faulty design features and statistical methods that are known to produce biased estimates of treatment efficacy. Conclusions The published statistical and methodological literatures provide clear guidance on methods to improve clinical trial design and analysis. Consistent use of state-of-the-art design features and analytic approaches will enhance the internal and external validity of treatment trials for AUDs across the spectrum of severity. The ultimate result of this attention to methodological rigor is that better treatment options will be identified for patients with an AUD. PMID:26250333
The antidepressant debate and the balanced placebo trial design: an ethical analysis.
Waring, Duff R
2008-12-01
There is ongoing debate about whether randomized, placebo-controlled trials under a double-blind have reliably established the pharmacological efficacy of antidepressants. Numerous meta-analyses of antidepressant efficacy trials, e.g., Kirsch et al. [Kirsch, I., Moore, T. J., Scoboria, A., & Nicholls, S. (2002). The emperor's new drugs: An analysis of antidepressant medication data submitted to the U.S. food and drug administration. Prevention and Treatment, 5, Article 23. (Retrieved July 19, 2007 from http://journals.apa.org/prevention/volume5)], have shown a modest drug-placebo difference but methodological problems with standard trial design preclude a definitive conclusion that this difference results from specific biological effects of antidepressants or the nonspecific factors that have not been adequately excluded. Standard trial design assumes the additivity thesis of pharmacological efficacy, being the assumption that the specific or "true" magnitude of the pharmacological effect is limited to the difference between the drug and placebo responses in a standard trial. If the drug effects are as small as these meta-analyses suggest, then their clinical effectiveness is questionable. If the drug effects are actually larger but masked by placebo effects, then the additivity thesis is not valid and we risk false negative results with standard trial design. Kirsch et al. propose an alternative, four arm balanced placebo trial design (BPTD) that can accurately test the additivity thesis. The BPTD uses antidepressants, active placebos and the intentional deception of research subjects. My focal question is whether the BPTD is ethically defensible. I will explore two objections that can be raised against it: 1) lying to BPTD research subjects violates their autonomy and exploits their illness and 2) the BPTD may not enable us to test the additivity thesis with accuracy, i.e., it may contribute to the masking of drug effects that it aims to avoid. I argue that these objections support the conclusion that the BPTD is ethically indefensible.
Precision Oncology: A New Era of Cancer Clinical Trials
Renfro, Lindsay A.; An, Ming-Wen; Mandrekar, Sumithra J.
2016-01-01
Traditionally, site of disease and anatomic staging have been used to define patient populations to be studied in individual cancer clinical trials. In the past decade, however, oncology has become increasingly understood on a cellular and molecular level, with many cancer subtypes being described as a function of biomarkers or tumor genetic mutations. With these changes in the science of oncology have come changes to the way we design and perform clinical trials. Increasingly common are trials tailored to detect enhanced efficacy in a patient subpopulation, e.g., patients with a known biomarker value or whose tumors harbor a specific genetic mutation. Here, we provide an overview of traditional and newer biomarker-based trial designs, and highlight lessons learned through implementation of several ongoing and recently completed trials. PMID:26987624
Considerations of study design.
Koretz, Ronald L
2007-12-01
Research projects attempt to answer specific questions. The particular study design that is selected will depend in large measure on the nature of the question and the time and resources available. There are 5 common categories of clinical questions; they relate to etiology, prognosis, utility of diagnostic tests, efficacy of proposed interventions, and cost of treatment in specific disease states. A number of study designs can be used. Case reports serve to memorialize unusual or novel aspects of diseases. Retrospective case series are useful for defining natural history. Case-control studies are used by epidemiologists to elucidate potential etiologies of diseases. Prospective cohort studies can be used to assess natural history or to assess potential disease etiologies. Controlled trials are designed to assess the efficacy of therapeutic interventions. Studies that define the sensitivity and specificity of diagnostic tests can be used to assess the utility of those tests. Economic analyses estimate the costs that particular diseases or therapies will require. Each of these study designs has limitations; with the exception of high-quality randomized trials, none of these study designs can establish a causative relationship between putative etiologic (or therapeutic) factors and disease (outcomes).
Clinical Trials Targeting Aging and Age-Related Multimorbidity
Crimmins, Eileen M; Grossardt, Brandon R; Crandall, Jill P; Gelfond, Jonathan A L; Harris, Tamara B; Kritchevsky, Stephen B; Manson, JoAnn E; Robinson, Jennifer G; Rocca, Walter A; Temprosa, Marinella; Thomas, Fridtjof; Wallace, Robert; Barzilai, Nir
2017-01-01
Abstract Background There is growing interest in identifying interventions that may increase health span by targeting biological processes underlying aging. The design of efficient and rigorous clinical trials to assess these interventions requires careful consideration of eligibility criteria, outcomes, sample size, and monitoring plans. Methods Experienced geriatrics researchers and clinical trialists collaborated to provide advice on clinical trial design. Results Outcomes based on the accumulation and incidence of age-related chronic diseases are attractive for clinical trials targeting aging. Accumulation and incidence rates of multimorbidity outcomes were developed by selecting at-risk subsets of individuals from three large cohort studies of older individuals. These provide representative benchmark data for decisions on eligibility, duration, and assessment protocols. Monitoring rules should be sensitive to targeting aging-related, rather than disease-specific, outcomes. Conclusions Clinical trials targeting aging are feasible, but require careful design consideration and monitoring rules. PMID:28364543
Hezel, Marcus; von Usslar, Kathrin; Kurzweg, Thiemo; Lörincz, Balazs B; Knecht, Rainald
2016-04-01
This article reviews the methodical and statistical basics of designing a trial, with a special focus on the process of defining and choosing endpoints and cutpoints as the foundations of clinical research, and ultimately that of evidence-based medicine. There has been a significant progress in the treatment of head and neck cancer in the past few decades. Currently available treatment options can have a variety of different goals, depending e.g. on tumor stage, among other factors. The outcome of a specific treatment in clinical trials is measured using endpoints. Besides classical endpoints, such as overall survival or organ preservation, other endpoints like quality of life are becoming increasingly important in designing and conducting a trial. The present work is based on electronic research and focuses on the solid methodical and statistical basics of a clinical trial, on the structure of study designs and on the presentation of various endpoints.
NASA Astrophysics Data System (ADS)
Boski, Marcin; Paszke, Wojciech
2015-11-01
This paper deals with the problem of designing an iterative learning control algorithm for discrete linear systems using repetitive process stability theory. The resulting design produces a stabilizing output feedback controller in the time domain and a feedforward controller that guarantees monotonic convergence in the trial-to-trial domain. The results are also extended to limited frequency range design specification. New design procedure is introduced in terms of linear matrix inequality (LMI) representations, which guarantee the prescribed performances of ILC scheme. A simulation example is given to illustrate the theoretical developments.
Placebo effect in clinical trial design for irritable bowel syndrome.
Shah, Eric; Pimentel, Mark
2014-04-30
Ongoing efforts to improve clinical trial design in irritable bowel syndrome have been hindered by high placebo response rates and ineffective outcome measures. We assessed established strategies to minimize placebo effect as well as the various ap-proaches to placebo effect which can affect trial design. These include genetic markers such as catechol-O-methyltransferase, opioidergic and dopaminergic neurobiologic theory, pre-cebo effect centered on expectancy theory, and side effect unblinding grounded on conditioning theory. We reviewed endpoints used in the study of IBS over the past decade including adequate relief and subjective global relief, emphasizing their weaknesses in fully evaluating the IBS condition, specifically their motility effects based on functional net value and relative benefit-harm based on dropouts due to adverse events. The focus of this review is to highlight ongoing efforts to improve clinical trial design which can lead to better outcomes in a real-world setting.
2012-01-01
Background In the last few years, excessive internet use and computer gaming have increased dramatically. Salience, mood modification, tolerance, withdrawal symptoms, conflict, and relapse have been defined as diagnostic criteria for internet addiction (IA) and computer addiction (CA) in the scientific community. Despite a growing number of individuals seeking help, there are no specific treatments of established efficacy. Methods/design This clinical trial aims to determine the effect of the disorder-specific manualized short-term treatment of IA/CA (STICA). The cognitive behavioural treatment combines individual and group interventions with a total duration of 4 months. Patients will be randomly assigned to STICA treatment or to a wait list control group. Reliable and valid measures of IA/CA and co-morbid mental symptoms (for example social anxiety, depression) will be assessed prior to the beginning, in the middle, at the end, and 6 months after completion of treatment. Discussion A treatment of IA/CA will establish efficacy and is desperately needed. As this is the first trial to determine efficacy of a disorder specific treatment, a wait list control group will be implemented. Pros and cons of the design were discussed. Trial Registration ClinicalTrials (NCT01434589) PMID:22540330
NASA Astrophysics Data System (ADS)
Wang, Ximing; Martinez, Clarisa; Wang, Jing; Liu, Ye; Liu, Brent
2014-03-01
Clinical trials usually have a demand to collect, track and analyze multimedia data according to the workflow. Currently, the clinical trial data management requirements are normally addressed with custom-built systems. Challenges occur in the workflow design within different trials. The traditional pre-defined custom-built system is usually limited to a specific clinical trial and normally requires time-consuming and resource-intensive software development. To provide a solution, we present a user customizable imaging informatics-based intelligent workflow engine system for managing stroke rehabilitation clinical trials with intelligent workflow. The intelligent workflow engine provides flexibility in building and tailoring the workflow in various stages of clinical trials. By providing a solution to tailor and automate the workflow, the system will save time and reduce errors for clinical trials. Although our system is designed for clinical trials for rehabilitation, it may be extended to other imaging based clinical trials as well.
Fisher, William A; Gruenwald, Ilan; Jannini, Emmanuele A; Lev-Sagie, Ahinoam; Lowenstein, Lior; Pyke, Robert E; Reisman, Yakov; Revicki, Dennis A; Rubio-Aurioles, Eusebio
2016-12-01
This series of articles outlines standards for clinical trials of treatments for male and female sexual dysfunctions, with a focus on research design and patient-reported outcome assessment. These articles consist of revision, updating, and integration of articles on standards for clinical trials in male and female sexual dysfunction from the 2010 International Consultation on Sexual Medicine developed by the authors as part of the 2015 International Consultation on Sexual Medicine. We are guided in this effort by several principles. In contrast to previous versions of these guidelines, we merge discussion of standards for clinical trials in male and female sexual dysfunction in an integrated approach that emphasizes the common foundational practices that underlie clinical trials in the two settings. We present a common expected standard for clinical trial design in male and female sexual dysfunction, a common rationale for the design of phase I to IV clinical trials, and common considerations for selection of study population and study duration in male and female sexual dysfunction. We present a focused discussion of fundamental principles in patient- (and partner-) reported outcome assessment and complete this series of articles with specific discussions of selected aspects of clinical trials that are unique to male and to female sexual dysfunction. Our consideration of standards for clinical trials in male and female sexual dysfunction attempts to embody sensitivity to existing and new regulatory guidance and to address implications of the evolution of the diagnosis of sexual dysfunction that have been brought forward in the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition. The first article in this series focuses on phase I to phase IV clinical trial design considerations. Subsequent articles in this series focus on the measurement of patient-reported outcomes, unique aspects of clinical trial design for men, and unique aspects of clinical trial design for women. Copyright © 2016 International Society for Sexual Medicine. Published by Elsevier Inc. All rights reserved.
Clinical Trial Design for HIV Prevention Research: Determining Standards of Prevention.
Dawson, Liza; Zwerski, Sheryl
2015-06-01
This article seeks to advance ethical dialogue on choosing standards of prevention in clinical trials testing improved biomedical prevention methods for HIV. The stakes in this area of research are high, given the continued high rates of infection in many countries and the budget limitations that have constrained efforts to expand treatment for all who are currently HIV-infected. New prevention methods are still needed; at the same time, some existing prevention and treatment interventions have been proven effective but are not yet widely available in the countries where they most urgently needed. The ethical tensions in this field of clinical research are well known and have been the subject of extensive debate. There is no single clinical trial design that can optimize all the ethically important goals and commitments involved in research. Several recent articles have described the current ethical difficulties in designing HIV prevention trials, especially in resource limited settings; however, there is no consensus on how to handle clinical trial design decisions, and existing international ethical guidelines offer conflicting advice. This article acknowledges these deep ethical dilemmas and moves beyond a simple descriptive approach to advance an organized method for considering what clinical trial designs will be ethically acceptable for HIV prevention trials, balancing the relevant criteria and providing justification for specific design decisions. Published 2014. This article is a U.S. Government work and is in the public domain in the USA.
The design and methodology of premature ejaculation interventional studies
2016-01-01
Large well-designed clinical efficacy and safety randomized clinical trials (RCTs) are required to achieve regulatory approval of new drug treatments. The objective of this article is to make recommendations for the criteria for defining and selecting the clinical trial study population, design and efficacy outcomes measures which comprise ideal premature ejaculation (PE) interventional trial methodology. Data on clinical trial design, epidemiology, definitions, dimensions and psychological impact of PE was reviewed, critiqued and incorporated into a series of recommendations for standardisation of PE clinical trial design, outcome measures and reporting using the principles of evidence based medicine. Data from PE interventional studies are only reliable, interpretable and capable of being generalised to patients with PE, when study populations are defined by the International Society for Sexual Medicine (ISSM) multivariate definition of PE. PE intervention trials should employ a double-blind RCT methodology and include placebo control, active standard drug control, and/or dose comparison trials. Ejaculatory latency time (ELT) and subject/partner outcome measures of control, personal/partner/relationship distress and other study-specific outcome measures should be used as outcome measures. There is currently no published literature which identifies a clinically significant threshold response to intervention. The ISSM definition of PE reflects the contemporary understanding of PE and represents the state-of-the-art multi-dimensional definition of PE and is recommended as the basis of diagnosis of PE for all PE clinical trials. PMID:27652224
Recommendations for the Design and Analysis of Treatment Trials for Alcohol Use Disorders.
Witkiewitz, Katie; Finney, John W; Harris, Alex H S; Kivlahan, Daniel R; Kranzler, Henry R
2015-09-01
Over the past 60 years, the view that "alcoholism" is a disease for which the only acceptable goal of treatment is abstinence has given way to the recognition that alcohol use disorders (AUDs) occur on a continuum of severity, for which a variety of treatment options are appropriate. However, because the available treatments for AUDs are not effective for everyone, more research is needed to develop novel and more efficacious treatments to address the range of AUD severity in diverse populations. Here we offer recommendations for the design and analysis of alcohol treatment trials, with a specific focus on the careful conduct of randomized clinical trials of medications and nonpharmacological interventions for AUDs. This paper provides a narrative review of the quality of published clinical trials and recommendations for the optimal design and analysis of treatment trials for AUDs. Despite considerable improvements in the design of alcohol clinical trials over the past 2 decades, many studies of AUD treatments have used faulty design features and statistical methods that are known to produce biased estimates of treatment efficacy. The published statistical and methodological literatures provide clear guidance on methods to improve clinical trial design and analysis. Consistent use of state-of-the-art design features and analytic approaches will enhance the internal and external validity of treatment trials for AUDs across the spectrum of severity. The ultimate result of this attention to methodological rigor is that better treatment options will be identified for patients with an AUD. Copyright © 2015 by the Research Society on Alcoholism.
Propensity Score Matching: Retrospective Randomization?
Jupiter, Daniel C
Randomized controlled trials are viewed as the optimal study design. In this commentary, we explore the strength of this design and its complexity. We also discuss some situations in which these trials are not possible, or not ethical, or not economical. In such situations, specifically, in retrospective studies, we should make every effort to recapitulate the rigor and strength of the randomized trial. However, we could be faced with an inherent indication bias in such a setting. Thus, we consider the tools available to address that bias. Specifically, we examine matching and introduce and explore a new tool: propensity score matching. This tool allows us to group subjects according to their propensity to be in a particular treatment group and, in so doing, to account for the indication bias. Copyright © 2017 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.
Some design issues in trials of microbicides for the prevention of HIV infection.
Fleming, Thomas R; Richardson, Barbra A
2004-08-15
Trials for the prevention of human immunodeficiency virus (HIV) infection that evaluate microbicides provide significant design challenges. Three of these design issues deserve more careful consideration. The first issue relates to the benefits of using both blinded and unblinded control groups when the placebo regimen may not be inert and when the effectiveness of an intervention heavily depends on behavioral, as well as biological, factors. The second issue relates to the strength of evidence required for regulatory approval for the marketing of drugs and biologics when only a single pivotal phase 3 clinical trial has provided such evidence. The third issue relates to the appropriate next step after the completion of phase 1 trials, as well as the specific merits of conducting phase 2b screening trials that assess the effects on the same clinical efficacy end point that will be the primary end point in a phase 3 trial. The issues considered in microbicide trials for the prevention of HIV infection are also of importance in many other clinical scenarios.
An optimal stratified Simon two-stage design.
Parashar, Deepak; Bowden, Jack; Starr, Colin; Wernisch, Lorenz; Mander, Adrian
2016-07-01
In Phase II oncology trials, therapies are increasingly being evaluated for their effectiveness in specific populations of interest. Such targeted trials require designs that allow for stratification based on the participants' molecular characterisation. A targeted design proposed by Jones and Holmgren (JH) Jones CL, Holmgren E: 'An adaptive Simon two-stage design for phase 2 studies of targeted therapies', Contemporary Clinical Trials 28 (2007) 654-661.determines whether a drug only has activity in a disease sub-population or in the wider disease population. Their adaptive design uses results from a single interim analysis to decide whether to enrich the study population with a subgroup or not; it is based on two parallel Simon two-stage designs. We study the JH design in detail and extend it by providing a few alternative ways to control the familywise error rate, in the weak sense as well as the strong sense. We also introduce a novel optimal design by minimising the expected sample size. Our extended design contributes to the much needed framework for conducting Phase II trials in stratified medicine. © 2016 The Authors Pharmaceutical Statistics Published by John Wiley & Sons Ltd. © 2016 The Authors Pharmaceutical Statistics Published by John Wiley & Sons Ltd.
Defining precision: The precision medicine initiative trials NCI-MPACT and NCI-MATCH.
Coyne, Geraldine O'Sullivan; Takebe, Naoko; Chen, Alice P
"Precision" trials, using rationally incorporated biomarker targets and molecularly selective anticancer agents, have become of great interest to both patients and their physicians. In the endeavor to test the cornerstone premise of precision oncotherapy, that is, determining if modulating a specific molecular aberration in a patient's tumor with a correspondingly specific therapeutic agent improves clinical outcomes, the design of clinical trials with embedded genomic characterization platforms which guide therapy are an increasing challenge. The National Cancer Institute Precision Medicine Initiative is an unprecedented large interdisciplinary collaborative effort to conceptualize and test the feasibility of trials incorporating sequencing platforms and large-scale bioinformatics processing that are not currently uniformly available to patients. National Cancer Institute-Molecular Profiling-based Assignment of Cancer Therapy and National Cancer Institute-Molecular Analysis for Therapy Choice are 2 genomic to phenotypic trials under this National Cancer Institute initiative, where treatment is selected according to predetermined genetic alterations detected using next-generation sequencing technology across a broad range of tumor types. In this article, we discuss the objectives and trial designs that have enabled the public-private partnerships required to complete the scale of both trials, as well as interim trial updates and strategic considerations that have driven data analysis and targeted therapy assignment, with the intent of elucidating further the benefits of this treatment approach for patients. Copyright © 2017. Published by Elsevier Inc.
Analysis and design of randomised clinical trials involving competing risks endpoints.
Tai, Bee-Choo; Wee, Joseph; Machin, David
2011-05-19
In randomised clinical trials involving time-to-event outcomes, the failures concerned may be events of an entirely different nature and as such define a classical competing risks framework. In designing and analysing clinical trials involving such endpoints, it is important to account for the competing events, and evaluate how each contributes to the overall failure. An appropriate choice of statistical model is important for adequate determination of sample size. We describe how competing events may be summarised in such trials using cumulative incidence functions and Gray's test. The statistical modelling of competing events using proportional cause-specific and subdistribution hazard functions, and the corresponding procedures for sample size estimation are outlined. These are illustrated using data from a randomised clinical trial (SQNP01) of patients with advanced (non-metastatic) nasopharyngeal cancer. In this trial, treatment has no effect on the competing event of loco-regional recurrence. Thus the effects of treatment on the hazard of distant metastasis were similar via both the cause-specific (unadjusted csHR = 0.43, 95% CI 0.25 - 0.72) and subdistribution (unadjusted subHR 0.43; 95% CI 0.25 - 0.76) hazard analyses, in favour of concurrent chemo-radiotherapy followed by adjuvant chemotherapy. Adjusting for nodal status and tumour size did not alter the results. The results of the logrank test (p = 0.002) comparing the cause-specific hazards and the Gray's test (p = 0.003) comparing the cumulative incidences also led to the same conclusion. However, the subdistribution hazard analysis requires many more subjects than the cause-specific hazard analysis to detect the same magnitude of effect. The cause-specific hazard analysis is appropriate for analysing competing risks outcomes when treatment has no effect on the cause-specific hazard of the competing event. It requires fewer subjects than the subdistribution hazard analysis for a similar effect size. However, if the main and competing events are influenced in opposing directions by an intervention, a subdistribution hazard analysis may be warranted.
Patient-oriented randomisation: A new trial design applied in the Neuroleptic Strategy Study.
Schulz, Constanze; Timm, Jürgen; Cordes, Joachim; Gründer, Gerhard; Mühlbauer, Bernd; Rüther, Eckart; Heinze, Martin
2016-06-01
The 'gold standard' for clinical studies is a randomised controlled trial usually comparing specific treatments. If the scientific study expands to strategy comparison with each strategy including various treatments, the research problems are increasingly complicated. The strategy debate in the psychiatric community is the starting point for the development of our new design. It is widely accepted that second-generation antipsychotics are the therapy of choice in the treatment of schizophrenia. However, their general superiority over first-generation antipsychotics could not be demonstrated in recent randomised controlled trials. Furthermore, we are becoming increasingly aware that the experimental conditions of randomised controlled trials, as in the European First Episode Schizophrenia Trial and Clinical Antipsychotic Trials of Intervention Effectiveness Phase 1 studies, may be inappropriate for psychiatric treatments. The high heterogeneity in the patient population produces discrepancies between daily clinical perception and randomised controlled trials results. The patient-oriented approach in the Cost Utility of the Latest Antipsychotic drugs in Schizophrenia Study reflects everyday clinical practice. The results, however, are highly dependent on the physicians' preferences. The goal of the design described here is to take an intermediate path between randomised controlled trials and clinical studies such as Cost Utility of the Latest Antipsychotic Drugs in Schizophrenia Study, combining the advantages of both study types. The idea is to randomise two treatment pairs each consisting of one first-generation antipsychotic and one second-generation antipsychotic in a first step and subsequently, to involve the investigators in deciding for a pair most appropriate to the patients' needs and then to randomise the allocation to one drug (first-generation antipsychotic or second-generation antipsychotic) of that chosen pair. This idea was first implemented in the clinical trial, the Neuroleptic Strategy Study, with a randomised design comparing efficacy and safety of two different strategies: either to use first-generation antipsychotics (haloperidol and flupentixol) or second-generation antipsychotics (olanzapine, aripiprazole and quetiapine) in patients suffering from schizophrenia. In the course of the Neuroleptic Strategy Study, feasibility of this design was demonstrated. All aspects of the new design were implemented: randomisation process, documentation of responses from investigators as well as patients and drug logistic experience. In implementing the design, furthermore, we could investigate its theoretical properties. The physicians' preferences for specific drugs used for the respective patients were analysed. The idea of patient-oriented randomisation can be generalised. In light of the heterogeneity and complexity of patient-drug interaction, this design should prove particularly useful. © The Author(s) 2016.
Huang, Peng; Ou, Ai-hua; Piantadosi, Steven; Tan, Ming
2014-11-01
We discuss the problem of properly defining treatment superiority through the specification of hypotheses in clinical trials. The need to precisely define the notion of superiority in a one-sided hypothesis test problem has been well recognized by many authors. Ideally designed null and alternative hypotheses should correspond to a partition of all possible scenarios of underlying true probability models P={P(ω):ω∈Ω} such that the alternative hypothesis Ha={P(ω):ω∈Ωa} can be inferred upon the rejection of null hypothesis Ho={P(ω):ω∈Ω(o)} However, in many cases, tests are carried out and recommendations are made without a precise definition of superiority or a specification of alternative hypothesis. Moreover, in some applications, the union of probability models specified by the chosen null and alternative hypothesis does not constitute a completed model collection P (i.e., H(o)∪H(a) is smaller than P). This not only imposes a strong non-validated assumption of the underlying true models, but also leads to different superiority claims depending on which test is used instead of scientific plausibility. Different ways to partition P fro testing treatment superiority often have different implications on sample size, power, and significance in both efficacy and comparative effectiveness trial design. Such differences are often overlooked. We provide a theoretical framework for evaluating the statistical properties of different specification of superiority in typical hypothesis testing. This can help investigators to select proper hypotheses for treatment comparison inclinical trial design. Copyright © 2014 Elsevier Inc. All rights reserved.
Corbett, Mark S; Watson, Judith; Eastwood, Alison
2016-10-19
We recently published a systematic review of different healthcare settings (such as outpatient, community or home) for administering intravenous chemotherapy, and concluded that performing conventionally designed randomised trials was difficult. The main problems were achieving adequate trial accrual rates and recruiting a study population which adequately represented the target population of interest. These issues stemmed from the fact that potential participants may have had pre-trial perceptions about the trial settings they may be allocated; such preferences will sometimes be strong enough for patients to decline an invitation to participate in a trial. A patient preference trial design (in which patients can choose, or be randomised to, an intervention) may have obviated these recruitment issues, although none of the trials used such a design. In order to gain a better understanding of the broader prevalence and extent of these preference issues (and any other methodological challenges), we undertook an exploratory review of settings trials in any area of healthcare treatment research. We searched The Cochrane Library and Google Scholar and used snowballing methods to identify trials comparing different healthcare settings. Trial accrual was affected by patient preferences for a setting in 15 of the 16 identified studies; birth setting trials were the most markedly affected, with between 68 % and 85 % of eligible women declining to participate specifically because of preference for a particular healthcare setting. Recruitment into substance abuse and chemotherapy setting studies was also notably affected by preferences. Only four trials used a preference design: the proportion of eligible patients choosing to participate via a preference group ranged from between 33 % and 67 %. In trials of healthcare settings, accrual may be seriously affected by patient preferences. The use of trial designs which incorporate a preference component should therefore strongly be considered. When designing such trials, investigators should consider settings to be complex interventions, which are likely to have linked components which may be difficult to control for. Careful thought is also needed regarding the choice of comparator settings and the most appropriate outcome measures to be used.
de Melo-Martín, Inmaculada; Sondhi, Dolan; Crystal, Ronald G
2011-09-01
For more than three decades clinical research in the United States has been explicitly guided by the idea that ethical considerations must be central to research design and practice. In spite of the centrality of this idea, attempting to balance the sometimes conflicting values of advancing scientific knowledge and protecting human subjects continues to pose challenges. Possible conflicts between the standards of scientific research and those of ethics are particularly salient in relation to trial design. Specifically, the choice of a control arm is an aspect of trial design in which ethical and scientific issues are deeply entwined. Although ethical quandaries related to the choice of control arms may arise when conducting any type of clinical trials, they are conspicuous in early phase gene transfer trials that involve highly novel approaches and surgical procedures and have children as the research subjects. Because of children's and their parents' vulnerabilities, in trials that investigate therapies for fatal, rare diseases affecting minors, the scientific and ethical concerns related to choosing appropriate controls are particularly significant. In this paper we use direct gene transfer to the central nervous system to treat late infantile neuronal ceroid lipofuscinosis to illustrate some of these ethical issues and explore possible solutions to real and apparent conflicts between scientific and ethical considerations.
This new clinical trial will collect samples of gastric tumor tissue from patients with the goal to use the molecular profiles to design treatments that work better by targeting a specific cancer tumor profile. Learn more...
2012-01-01
There is a critical need for new pathways to develop antibacterial agents to treat life-threatening infections caused by highly resistant bacteria. Traditionally, antibacterial agents have been studied in noninferiority clinical trials that focus on one site of infection (eg, pneumonia, intra-abdominal infection). Conduct of superiority trials for infections caused by highly antibiotic-resistant bacteria represents a new, and as yet, untested paradigm for antibacterial drug development. We sought to define feasible trial designs of antibacterial agents that could enable conduct of superiority and organism-specific clinical trials. These recommendations are the results of several years of active dialogue among the white paper's drafters as well as external collaborators and regulatory officials. Our goal is to facilitate conduct of new types of antibacterial clinical trials to enable development and ultimately approval of critically needed new antibacterial agents. PMID:22891041
Design of clinical trials for new drugs in animals.
Muser, R K
1980-05-15
Consideration of the intended purpose, an effort to ask specific questions that can be answered by specific data, selection of the correct values to be measured, and investigators who are able to conduct the study, will make it possible to design clinical studies properly. The ethical need to avoid unnecessary suffering of experimental animals and rules and regulations in effect at the time of clinical trials will dictate certain aspects of the design. The type of product to be evaluated, its mode of administration, the type of animal in which the drug will be used, the type of investigator who will collect the data, and the individual who will use the drug, will determine the mechanical part of the protocol. All of these factors need to be considered and discussed with all participants, which may include biostatisticians, regulatory authorities, investigators, and other individuals, to ensure that a rational design is chosen.
Opie, Rachelle S; O'Neil, Adrienne; Jacka, Felice N; Pizzinga, Josephine; Itsiopoulos, Catherine
2017-04-19
The SMILES trial was the first randomized controlled trial (RCT) explicitly designed to evaluate a dietary intervention, conducted by qualified dietitians, for reducing depressive symptomatology in adults with clinical depression. Here we detail the development of the prescribed diet (modified Mediterranean diet (ModiMedDiet)) for individuals with major depressive disorders (MDDs) that was designed specifically for the SMILES trial. We also present data demonstrating the extent to which this intervention achieved improvements in diet quality. The ModiMedDiet was designed using a combination of existing dietary guidelines and scientific evidence from the emerging field of nutritional psychiatric epidemiology. Sixty-seven community dwelling individuals (Melbourne, Australia) aged 18 years or over, with current poor quality diets, and MDDs were enrolled into the SMILES trial. A retention rate of 93.9 and 73.5% was observed for the dietary intervention and social support control group, respectively. The dietary intervention (ModiMedDiet) consisted of seven individual nutrition counselling sessions delivered by a qualified dietitian. The control condition comprised a social support protocol matched to the same visit schedule and length. This manuscript details the first prescriptive individualized dietary intervention delivered by dietitians for adults with major depression. Significant improvements in dietary quality were observed among individuals randomized to the ModiMedDiet group. These dietary improvements were also found to be associated with changes in depressive symptoms. The ModiMedDiet, a novel and individually tailored intervention designed specifically for adults with major depression, can be effectively implemented in clinical practice to manage this highly prevalent and debilitating condition. Australia and New Zealand Clinical Trials Register (ANZCTR): ACTRN12612000251820. Registered 29 February 2012.
Cabana, Michael D; Vidry, Stéphane; Merenstein, Dan; Hummelen, Ruben; Ellis, Collin L; Heimbach, James T; Hempel, Susanne; Lynch, Susan V; Sanders, Mary Ellen; Tancredi, Daniel J
2010-01-01
The heterogeneity of human clinical trials to assess the effectiveness of probiotics presents challenges regarding interpretation and comparison. Evidence obtained from clinical trials among a population with a disease or specific risk factors may not be generalizable to healthy individuals. The evaluation of interventions in healthy persons requires careful selection of outcomes due to the absence of health indicators and the low incidence of preventable conditions. Given the tremendous resources invested in such trials, development of consistent approaches to assessing the effectiveness of probiotics would be beneficial. Furthermore, the reporting, presentation and communication of results may also affect the validity of the scientific evidence obtained from a trial. This review outlines the challenges associated with the design, implementation, data analysis and interpretation of clinical trials in humans involving probiotics. Best practices related to their design are offered along with recommendations for enhanced collaboration to advance research in this emerging field. PMID:21327031
The challenge of comorbidity in clinical trials for multiple sclerosis.
Marrie, Ruth Ann; Miller, Aaron; Sormani, Maria Pia; Thompson, Alan; Waubant, Emmanuelle; Trojano, Maria; O'Connor, Paul; Reingold, Stephen; Cohen, Jeffrey A
2016-04-12
We aimed to provide recommendations for addressing comorbidity in clinical trial design and conduct in multiple sclerosis (MS). We held an international workshop, informed by a systematic review of the incidence and prevalence of comorbidity in MS and an international survey about research priorities for studying comorbidity including their relation to clinical trials in MS. We recommend establishing age- and sex-specific incidence estimates for comorbidities in the MS population, including those that commonly raise concern in clinical trials of immunomodulatory agents; shifting phase III clinical trials of new therapies from explanatory to more pragmatic trials; describing comorbidity status of the enrolled population in publications reporting clinical trials; evaluating treatment response, tolerability, and safety in clinical trials according to comorbidity status; and considering comorbidity status in the design of pharmacovigilance strategies. Our recommendations will help address knowledge gaps regarding comorbidity that interfere with the ability to interpret safety in monitored trials and will enhance the generalizability of findings from clinical trials to "real world" settings where the MS population commonly has comorbid conditions. © 2016 American Academy of Neurology.
The challenge of comorbidity in clinical trials for multiple sclerosis
Miller, Aaron; Sormani, Maria Pia; Thompson, Alan; Waubant, Emmanuelle; Trojano, Maria; O'Connor, Paul; Reingold, Stephen; Cohen, Jeffrey A.
2016-01-01
Objective: We aimed to provide recommendations for addressing comorbidity in clinical trial design and conduct in multiple sclerosis (MS). Methods: We held an international workshop, informed by a systematic review of the incidence and prevalence of comorbidity in MS and an international survey about research priorities for studying comorbidity including their relation to clinical trials in MS. Results: We recommend establishing age- and sex-specific incidence estimates for comorbidities in the MS population, including those that commonly raise concern in clinical trials of immunomodulatory agents; shifting phase III clinical trials of new therapies from explanatory to more pragmatic trials; describing comorbidity status of the enrolled population in publications reporting clinical trials; evaluating treatment response, tolerability, and safety in clinical trials according to comorbidity status; and considering comorbidity status in the design of pharmacovigilance strategies. Conclusion: Our recommendations will help address knowledge gaps regarding comorbidity that interfere with the ability to interpret safety in monitored trials and will enhance the generalizability of findings from clinical trials to “real world” settings where the MS population commonly has comorbid conditions. PMID:26888986
Characteristics of NIH- and industry-sponsored head and neck cancer clinical trials.
Devaiah, Anand; Murchison, Charles
2016-09-01
Compare U.S. clinical trials sponsored by the National Institutes of Health (NIH) and industry, especially with regard to trial design, interventions studied, and results reporting rates. U.S. head and neck cancer clinical trials. We used information from ClinicalTrials.gov to compare NIH- and industry-sponsored head and neck cancer clinical trials, specifically analyzing differences in trial design and interventions studied. We examined publication rates and positive results rates using PubMed.gov. About 50% of NIH- and industry-sponsored clinical trials have their results reported in peer-reviewed literature. Industry-sponsored trials had higher rates of positive results than NIH-sponsored trials. NIH- and industry-sponsored clinical trials had similar trial designs, although industry-sponsored trials had significantly lower rates of randomization. Industry trials utilized radiation in 19% of trials and surgery in 2% of trials. NIH trials also had low utilization of both radiation and surgery (27% and 12% of trials, respectively). NIH- and industry-sponsored trials published their results in journals with comparable impact factors. There is significant underreporting of results in U.S. head and neck cancer clinical trials, whether sponsored by NIH or industry. Industry trials have significantly higher rates of positive results, although it is unclear what contributes to this. Both NIH- and industry-sponsored trials underutilize surgery and radiation as treatment modalities, despite the fact that these are standard-of-care therapies for head and neck cancer. We recommend that the NIH and industry report all results from clinical trials and use surgery and radiation as treatment arms in order to arrive at more balanced therapeutic recommendations. N/A. Laryngoscope, 126:E300-E303, 2016. © 2016 The American Laryngological, Rhinological and Otological Society, Inc.
Adaptive Clinical Trials: Advantages and Disadvantages of Various Adaptive Design Elements.
Korn, Edward L; Freidlin, Boris
2017-06-01
There is a wide range of adaptive elements of clinical trial design (some old and some new), with differing advantages and disadvantages. Classical interim monitoring, which adapts the design based on early evidence of superiority or futility of a treatment arm, has long been known to be extremely useful. A more recent application of interim monitoring is in the use of phase II/III designs, which can be very effective (especially in the setting of multiple experimental treatments and a reliable intermediate end point) but do have the cost of having to commit earlier to the phase III question than if separate phase II and phase III trials were performed. Outcome-adaptive randomization is an older technique that has recently regained attention; it increases trial complexity and duration without offering substantial benefits to the patients in the trial. The use of adaptive trials with biomarkers is new and has great potential for efficiently identifying patients who will be helped most by specific treatments. Master protocols in which trial arms and treatment questions are added to an ongoing trial can be especially efficient in the biomarker setting, where patients are screened for entry into different subtrials based on evolving knowledge about targeted therapies. A discussion of three recent adaptive clinical trials (BATTLE-2, I-SPY 2, and FOCUS4) highlights the issues. Published by Oxford University Press 2017. This work is written by US Government employees and is in the public domain in the US.
2013-01-01
Background Chronic heart failure (HF) disease management programs have reported inconsistent results and have not included comorbid depression management or specifically focused on improving patient-reported outcomes. The Patient Centered Disease Management (PCDM) trial was designed to test the effectiveness of collaborative care disease management in improving health status (symptoms, functioning, and quality of life) in patients with HF who reported poor HF-specific health status. Methods/design Patients with a HF diagnosis at four VA Medical Centers were identified through population-based sampling. Patients with a Kansas City Cardiomyopathy Questionnaire (KCCQ, a measure of HF-specific health status) score of < 60 (heavy symptom burden and impaired quality of life) were invited to enroll in the PCDM trial. Enrolled patients were randomized to receive usual care or the PCDM intervention, which included: (1) collaborative care management by VA clinicians including a nurse, cardiologist, internist, and psychiatrist, who worked with patients and their primary care providers to provide guideline-concordant care management, (2) home telemonitoring and guided patient self-management support, and (3) screening and treatment for comorbid depression. The primary study outcome is change in overall KCCQ score. Secondary outcomes include depression, medication adherence, guideline-based care, hospitalizations, and mortality. Discussion The PCDM trial builds on previous studies of HF disease management by prioritizing patient health status, implementing a collaborative care model of health care delivery, and addressing depression, a key barrier to optimal disease management. The study has been designed as an ‘effectiveness trial’ to support broader implementation in the healthcare system if it is successful. Trial registration Unique identifier: NCT00461513 PMID:23837415
Implementation of psychological clinical trials in epilepsy: Review and guide.
Modi, Avani C; Wagner, Janelle; Smith, Aimee W; Kellermann, Tanja S; Michaelis, Rosa
2017-09-01
The International League Against Epilepsy (ILAE) Neuropsychiatry commission and United States Institute of Medicine report both identified cognitive and psychological comorbidities as a significant issue for individuals with epilepsy, with rates as high as 60%. However, there is a paucity of evidence-based treatments for many psychological conditions (e.g., learning disorders, cognitive disorders, behavioral disorders). Because of inherent challenges in the implementation of psychological therapy trials and specific considerations for the population with epilepsy, the focus of the current review was to provide guidance and recommendations to conduct psychological trials for individuals with epilepsy. Several key areas will be discussed, including selection of patients, trial design, psychological intervention considerations, outcomes and evaluation of results, publication of trial results, and special issues related to pediatric clinical trials. Rigorously designed psychological therapy trials will set the stage for evidence-based practice in the care of individuals with epilepsy, with the goal of improving seizures, side effects, and HRQOL. Copyright © 2017 Elsevier Inc. All rights reserved.
2011-01-01
Background Effective treatment strategies for chronic depression are urgently needed since it is not only a common and particularly disabling disorder, but is also considered treatment resistant by most clinicians. There are only a few studies on chronic depression indicating that traditional psycho- and pharmacological interventions are not as effective as in acute, episodic depression. Current medications are no more effective than those introduced 50 years ago whereas the only psychotherapy developed specifically for the subgroup of chronic depression, the Cognitive Behavioral Analysis System of Psychotherapy (CBASP), faired well in one large trial. However, CBASP has never been directly compared to a non-specific control treatment. Methods/Design The present article describes the study protocol of a multisite parallel-group randomized controlled trial in Germany. The purpose of the study is to estimate the efficacy of CBASP compared to supportive psychotherapy in 268 non-medicated early-onset chronically depressed outpatients. The intervention includes 20 weeks of acute treatment with 24 individual sessions followed by 28 weeks of continuation treatment with another 8 sessions. Depressive symptoms are evaluated 20 weeks after randomisation by means of the 24-item Hamilton Rating Scale of Depression (HRSD). Secondary endpoints are depressive symptoms after 12 and 48 weeks, and remission after 12, 20, and 48 weeks. Primary outcome will be analysed using analysis of covariance (ANCOVA) controlled for pre-treatment scores and site. Analyses of continuous secondary variables will be performed using linear mixed models. For remission rates, chi-squared tests and logistic regression will be applied. Discussion The study evaluates the comparative effects of a disorder-specific psychotherapy and a well designed non-specific psychological approach in the acute and continuation treatment phase in a large sample of early-onset chronically depressed patients. Trial registration ClinicalTrials.gov (NCT00970437). PMID:21849054
Navas-Carretero, Santiago; Martinez, J Alfredo
2015-07-01
The growing worldwide interest on functional food research has been accompanied by increasing regulatory guidelines in this area, with the aim of ensuring that any claimed effect in foods, beyond their nutritional role, is based on scientific unequivocal evidence. In order to assess the cause-effect relationship between the regular consumption of a food or a food component and the beneficial outcome for the consumer, an appropriate study design is required. Previous knowledge and research on the specific claimed food or product may be an adequate basis for defining a hypothesis and accurate objectives. Other key factors to take into account are based on the outcomes studied, the length of the trial, sample size and type, as well as the transparency on reporting the results obtained. Based on the Consolidated Standards on Reporting Trials statement (CONSORT), together with the specific guidelines published by the European Food Safety Authority (EFSA) Panel on Dietetic Products, Nutrition and Allergies, the present article aims at summarizing key questions conducting to the most appropriate study design for solid health claim substantiation.
Bayesian Phase II optimization for time-to-event data based on historical information.
Bertsche, Anja; Fleischer, Frank; Beyersmann, Jan; Nehmiz, Gerhard
2017-01-01
After exploratory drug development, companies face the decision whether to initiate confirmatory trials based on limited efficacy information. This proof-of-concept decision is typically performed after a Phase II trial studying a novel treatment versus either placebo or an active comparator. The article aims to optimize the design of such a proof-of-concept trial with respect to decision making. We incorporate historical information and develop pre-specified decision criteria accounting for the uncertainty of the observed treatment effect. We optimize these criteria based on sensitivity and specificity, given the historical information. Specifically, time-to-event data are considered in a randomized 2-arm trial with additional prior information on the control treatment. The proof-of-concept criterion uses treatment effect size, rather than significance. Criteria are defined on the posterior distribution of the hazard ratio given the Phase II data and the historical control information. Event times are exponentially modeled within groups, allowing for group-specific conjugate prior-to-posterior calculation. While a non-informative prior is placed on the investigational treatment, the control prior is constructed via the meta-analytic-predictive approach. The design parameters including sample size and allocation ratio are then optimized, maximizing the probability of taking the right decision. The approach is illustrated with an example in lung cancer.
Building clinical trial capacity to develop a new treatment for multidrug-resistant tuberculosis.
Tupasi, Thelma; Gupta, Rajesh; Danilovits, Manfred; Cirule, Andra; Sanchez-Garavito, Epifanio; Xiao, Heping; Cabrera-Rivero, Jose L; Vargas-Vasquez, Dante E; Gao, Mengqiu; Awad, Mohamed; Gentry, Leesa M; Geiter, Lawrence J; Wells, Charles D
2016-02-01
New drugs for infectious diseases often need to be evaluated in low-resource settings. While people working in such settings often provide high-quality care and perform operational research activities, they generally have less experience in conducting clinical trials designed for drug approval by stringent regulatory authorities. We carried out a capacity-building programme during a multi-centre randomized controlled trial of delamanid, a new drug for the treatment of multidrug-resistant tuberculosis. The programme included: (i) site identification and needs assessment; (ii) achieving International Conference on Harmonization - Good Clinical Practice (ICH-GCP) standards; (iii) establishing trial management; and (iv) increasing knowledge of global and local regulatory issues. Trials were conducted at 17 sites in nine countries (China, Egypt, Estonia, Japan, Latvia, Peru, the Philippines, the Republic of Korea and the United States of America). Eight of the 10 sites in low-resource settings had no experience in conducting the requisite clinical trials. Extensive capacity-building was done in all 10 sites. The programme resulted in improved local capacity in key areas such as trial design, data safety and monitoring, trial conduct and laboratory services. Clinical trials designed to generate data for regulatory approval require additional efforts beyond traditional research-capacity strengthening. Such capacity-building approaches provide an opportunity for product development partnerships to improve health systems beyond the direct conduct of the specific trial.
The Development of a Minority Recruitment Plan for Cancer Clinical Trials
Trevino, Monica; Padalecki, Susan; Karnad, Anand; Parra, Alberto; Weitman, Steve; Nashawati, Melissa; Pollock, Brad H.; Ramirez, Amelie; Thompson, Ian M.
2014-01-01
Background Cancer does not occur in all ethnic and racial groups at similar rates. In addition, responses to treatment also vary in certain ethnic and racial groups. For Hispanics, the overall cancer incidence is generally lower yet for some specific tumor types, the incidence rates are higher compared to other populations. Objectives Although disparities are recognized for treatment outcomes and prevention methodologies for Hispanics and other minority populations, specific recruiting and reporting of minorities remains a challenge. In order to circumvent this problem, the Cancer Therapy and Research Center (CTRC) has developed a new minority recruitment plan for all cancer related clinical trials at this Institute. The overall goal of this initiative is to increase the accrual of minorities in cancer clinical trials by implementing several key interventions. Method The Cancer Therapy & Research Center (CTRC) at the University of Texas Health Science Center at San Antonio established the Clinical Trials Accrual Task Force to develop and monitor interventions designed to increase accrual to cancer clinical trials, specifically the accrual of minorities with a focus on the Hispanic population that makes up 68% of the CTRC's catchment area. Results A Minority Accrual Plan (MAP) was implemented in March 2013 as part of the process for initiating and conducting cancer-related clinical trials at the CTRC. The Minority Accrual Plan focuses on Hispanic enrollment due to the characteristics of the South Texas population served by the CTRC but could be easily adapted to other populations. Conclusions The CTRC has designed a process to prospectively address the challenge of deliberately enrolling minority subjects and accurately accounting for the results by implementing a Minority Accrual Plan for every cancer-related clinical trial at CTRC. PMID:25152846
The Development of a Minority Recruitment Plan for Cancer Clinical Trials.
Trevino, Monica; Padalecki, Susan; Karnad, Anand; Parra, Alberto; Weitman, Steve; Nashawati, Melissa; Pollock, Brad H; Ramirez, Amelie; Thompson, Ian M
2013-09-01
Cancer does not occur in all ethnic and racial groups at similar rates. In addition, responses to treatment also vary in certain ethnic and racial groups. For Hispanics, the overall cancer incidence is generally lower yet for some specific tumor types, the incidence rates are higher compared to other populations. Although disparities are recognized for treatment outcomes and prevention methodologies for Hispanics and other minority populations, specific recruiting and reporting of minorities remains a challenge. In order to circumvent this problem, the Cancer Therapy and Research Center (CTRC) has developed a new minority recruitment plan for all cancer related clinical trials at this Institute. The overall goal of this initiative is to increase the accrual of minorities in cancer clinical trials by implementing several key interventions. The Cancer Therapy & Research Center (CTRC) at the University of Texas Health Science Center at San Antonio established the Clinical Trials Accrual Task Force to develop and monitor interventions designed to increase accrual to cancer clinical trials, specifically the accrual of minorities with a focus on the Hispanic population that makes up 68% of the CTRC's catchment area. A Minority Accrual Plan (MAP) was implemented in March 2013 as part of the process for initiating and conducting cancer-related clinical trials at the CTRC. The Minority Accrual Plan focuses on Hispanic enrollment due to the characteristics of the South Texas population served by the CTRC but could be easily adapted to other populations. The CTRC has designed a process to prospectively address the challenge of deliberately enrolling minority subjects and accurately accounting for the results by implementing a Minority Accrual Plan for every cancer-related clinical trial at CTRC.
Van Patten, Cheri L; de Boer, Johan G; Tomlinson Guns, Emma S
2008-12-01
We review the effect of diet and dietary supplement interventions on prostate cancer progression, recurrence and survival. A literature search was conducted in MEDLINE, EMBASE and CINAHL to identify diet and dietary supplement intervention studies in men with prostate cancer using prostate specific antigen or prostate specific antigen doubling time as a surrogate serum biomarker of prostate cancer recurrence and/or survival. Of the 32 studies identified 9 (28%) were randomized controlled trials and the focus of this review. In these studies men had confirmed prostate cancer and elevated or increasing prostate specific antigen. Only 1 trial included men with metastatic disease. When body mass index was reported, men were overweight or obese. A significant decrease in prostate specific antigen was observed in some studies using a low fat vegan diet, soy beverage or lycopene supplement. While not often reported as an end point, a significant increase in prostate specific antigen doubling time was observed in a study on lycopene supplementation. In only 1 randomized controlled trial in men undergoing orchiectomy was a survival end point of fewer deaths with lycopene supplementation reported. A limited number of randomized controlled trials were identified in which diet and dietary supplement interventions appeared to slow disease progression in men with prostate cancer, although results vary. Studies were limited by reliance on the surrogate biomarker prostate specific antigen, sample size and study duration. Well designed trials are warranted to expand knowledge, replicate findings and further assess the impact of diet and dietary supplement interventions on recurrence and treatment associated morbidities.
Paller, Channing J.; Bradbury, Penelope A.; Ivy, S. Percy; Seymour, Lesley; LoRusso, Patricia M.; Baker, Laurence; Rubinstein, Larry; Huang, Erich; Collyar, Deborah; Groshen, Susan; Reeves, Steven; Ellis, Lee M.; Sargent, Daniel J.; Rosner, Gary L.; LeBlanc, Michael L.; Ratain, Mark J.
2014-01-01
Anticancer drugs are combined in an effort to treat a heterogeneous tumor or to maximize the pharmacodynamic effect. The development of combination regimens, while desirable, poses unique challenges. These include the selection of agents for combination therapy that may lead to improved efficacy while maintaining acceptable toxicity, the design of clinical trials that provide informative results for individual agents and combinations, and logistical and regulatory challenges. The phase 1 trial is often the initial step in the clinical evaluation of a combination regimen. In view of the importance of combination regimens and the challenges associated with developing them, the Clinical Trial Design (CTD) Task Force of the National Cancer Institute (NCI) Investigational Drug Steering Committee developed a set of recommendations for the phase 1 development of a combination regimen. The first two recommendations focus on the scientific rationale and development plans for the combination regimen; subsequent recommendations encompass clinical design aspects. The CTD Task Force recommends that selection of the proposed regimens be based on a biological or pharmacological rationale supported by clinical and/or robust and validated preclinical evidence, and accompanied by a plan for subsequent development of the combination. The design of the phase 1 clinical trial should take into consideration the potential pharmacokinetic and pharmacodynamic interactions as well as overlapping toxicity. Depending on the specific hypothesized interaction, the primary endpoint may be dose optimization, pharmacokinetics, and/or pharmacodynamic (i.e., biomarker). PMID:25125258
Schmoll, Hans-Joachim; Arnold, Dirk; de Gramont, Aimery; Ducreux, Michel; Grothey, Axel; O'Dwyer, Peter J; Van Cutsem, Eric; Hermann, Frank; Bosanac, Ivan; Bendahmane, Belguendouz; Mancao, Christoph; Tabernero, Josep
2018-06-01
The old approach of one therapeutic for all patients with mCRC is evolving with a need to target specific molecular aberrations or cell-signalling pathways. Molecular screening approaches and new biomarkers are required to fully characterize tumours, identify patients most likely to benefit, and predict treatment response. MODUL is a signal-seeking trial with a design that is highly adaptable, permitting modification of different treatment cohorts and inclusion of further additional cohorts based on novel evidence on new compounds/combinations that emerge during the study. MODUL is ongoing and its adaptable nature permits timely and efficient recruitment of patients into the most appropriate cohort. Recruitment will take place over approximately 5 years in Europe, Asia, Africa, and South America. The design of MODUL with ongoing parallel/sequential treatment cohorts means that the overall size and duration of the trial can be modified/prolonged based on accumulation of new data. The early success of the current trial suggests that the design may provide definitive leads in a patient-friendly and relatively economical trial structure. Along with other biomarker-driven trials that are currently underway, it is hoped that MODUL will contribute to the continuing evolution of clinical trial design and permit a more 'tailored' approach to the treatment of patients with mCRC.
de Melo-Martín, Inmaculada; Sondhi, Dolan
2011-01-01
Abstract For more than three decades clinical research in the United States has been explicitly guided by the idea that ethical considerations must be central to research design and practice. In spite of the centrality of this idea, attempting to balance the sometimes conflicting values of advancing scientific knowledge and protecting human subjects continues to pose challenges. Possible conflicts between the standards of scientific research and those of ethics are particularly salient in relation to trial design. Specifically, the choice of a control arm is an aspect of trial design in which ethical and scientific issues are deeply entwined. Although ethical quandaries related to the choice of control arms may arise when conducting any type of clinical trials, they are conspicuous in early phase gene transfer trials that involve highly novel approaches and surgical procedures and have children as the research subjects. Because of children's and their parents' vulnerabilities, in trials that investigate therapies for fatal, rare diseases affecting minors, the scientific and ethical concerns related to choosing appropriate controls are particularly significant. In this paper we use direct gene transfer to the central nervous system to treat late infantile neuronal ceroid lipofuscinosis to illustrate some of these ethical issues and explore possible solutions to real and apparent conflicts between scientific and ethical considerations. PMID:21446781
Wages, Nolan A; Read, Paul W; Petroni, Gina R
2015-01-01
Dose-finding studies that aim to evaluate the safety of single agents are becoming less common, and advances in clinical research have complicated the paradigm of dose finding in oncology. A class of more complex problems, such as targeted agents, combination therapies and stratification of patients by clinical or genetic characteristics, has created the need to adapt early-phase trial design to the specific type of drug being investigated and the corresponding endpoints. In this article, we describe the implementation of an adaptive design based on a continual reassessment method for heterogeneous groups, modified to coincide with the objectives of a Phase I/II trial of stereotactic body radiation therapy in patients with painful osseous metastatic disease. Operating characteristics of the Institutional Review Board approved design are demonstrated under various possible true scenarios via simulation studies. Copyright © 2015 John Wiley & Sons, Ltd.
Jackson, Hollie J; Rafiq, Sarwish; Brentjens, Renier J
2016-06-01
The engineered expression of chimeric antigen receptors (CARs) on the surface of T cells enables the redirection of T-cell specificity. Early clinical trials using CAR T cells for the treatment of patients with cancer showed modest results, but the impressive outcomes of several trials of CD19-targeted CAR T cells in the treatment of patients with B-cell malignancies have generated an increased enthusiasm for this approach. Important lessons have been derived from clinical trials of CD19-specific CAR T cells, and ongoing clinical trials are testing CAR designs directed at novel targets involved in haematological and solid malignancies. In this Review, we discuss these trials and present strategies that can increase the antitumour efficacy and safety of CAR T-cell therapy. Given the fast-moving nature of this field, we only discuss studies with direct translational application currently or soon-to-be tested in the clinical setting.
Jackson, Hollie J.; Rafiq, Sarwish; Brentjens, Renier J.
2017-01-01
The engineered expression of chimeric antigen receptors (CARs) on the surface of T cells enables the redirection of T-cell specificity. Early clinical trials using CAR T cells for the treatment of patients with cancer showed modest results, but the impressive outcomes of several trials of CD19-targeted CAR T cells in the treatment of patients with B-cell malignancies have generated an increased enthusiasm for this approach. Important lessons have been derived from clinical trials of CD19-specific CAR T cells, and ongoing clinical trials are testing CAR designs directed at novel targets involved in haematological and solid malignancies. In this Review, we discuss these trials and present strategies that can increase the antitumour efficacy and safety of CAR T-cell therapy. Given the fast-moving nature of this field, we only discuss studies with direct translational application currently or soon-to-be tested in the clinical setting. PMID:27000958
Hussain, Maha; Tangen, Catherine; Higano, Celestia; Vogelzang, Nicholas; Thompson, Ian
2016-01-20
Intermittent androgen deprivation (IAD) has been widely tested in prostate cancer. However, phase III trials testing continuous androgen deprivation (CAD) versus IAD have reached inconclusive and seemingly contradictory results. Different design and conduct issues must be critically evaluated to better interpret the results. Seven published phase III trials were examined for prespecified design and outcomes. Treatment specifications; primary end point; superiority versus noninferiority design assumptions, including magnitude of assumed versus observed noninferiority margin (NIM); duration of follow-up; and quality-of-life (QOL) outcomes were considered in terms of the results and conclusions reported. Five trials had a superiority and three had a noninferiority primary hypothesis. Only three trials had a uniform population and overall survival (OS) end point. All trials observed better outcomes in terms of OS and progression-free survival (PFS) than assumed at time of study design, translating into prespecified NIMs or hazard ratios that reflected larger absolute differences in OS or PFS between arms. Lower-than-expected event rates also reduced statistical power for the trials. Other factors, including length of follow-up, cause of death, QOL, and primary end point, and their impact on trial interpretation are discussed. No trial to date has demonstrated survival superiority of IAD compared with CAD. Trials concluding IAD is noninferior to CAD were based on wide NIMs that included clinically important survival differences, not likely to be considered comparable by physicians or patients. Interim analyses relying on short follow-up and including a majority of non-prostate cancer deaths will favor a noninferiority conclusion and should be interpreted cautiously. Adequate follow-up is required to ensure capture of prostate cancer deaths in both superiority and noninferiority trials. © 2015 by American Society of Clinical Oncology.
GOST: A generic ordinal sequential trial design for a treatment trial in an emerging pandemic.
Whitehead, John; Horby, Peter
2017-03-01
Conducting clinical trials to assess experimental treatments for potentially pandemic infectious diseases is challenging. Since many outbreaks of infectious diseases last only six to eight weeks, there is a need for trial designs that can be implemented rapidly in the face of uncertainty. Outbreaks are sudden and unpredictable and so it is essential that as much planning as possible takes place in advance. Statistical aspects of such trial designs should be evaluated and discussed in readiness for implementation. This paper proposes a generic ordinal sequential trial design (GOST) for a randomised clinical trial comparing an experimental treatment for an emerging infectious disease with standard care. The design is intended as an off-the-shelf, ready-to-use robust and flexible option. The primary endpoint is a categorisation of patient outcome according to an ordinal scale. A sequential approach is adopted, stopping as soon as it is clear that the experimental treatment has an advantage or that sufficient advantage is unlikely to be detected. The properties of the design are evaluated using large-sample theory and verified for moderate sized samples using simulation. The trial is powered to detect a generic clinically relevant difference: namely an odds ratio of 2 for better rather than worse outcomes. Total sample sizes (across both treatments) of between 150 and 300 patients prove to be adequate in many cases, but the precise value depends on both the magnitude of the treatment advantage and the nature of the ordinal scale. An advantage of the approach is that any erroneous assumptions made at the design stage about the proportion of patients falling into each outcome category have little effect on the error probabilities of the study, although they can lead to inaccurate forecasts of sample size. It is important and feasible to pre-determine many of the statistical aspects of an efficient trial design in advance of a disease outbreak. The design can then be tailored to the specific disease under study once its nature is better understood.
Oyarzún, Patricio; Kobe, Bostjan
2016-03-03
Novel vaccination approaches based on rational design of B- and T-cell epitopes - epitope-based vaccines - are making progress in the clinical trial pipeline. The epitope-focused recombinant protein-based malaria vaccine (termed RTS,S) is a next-generation approach that successfully reached phase-III trials, and will potentially become the first commercial vaccine against a human parasitic disease. Progress made on methods such as recombinant DNA technology, advanced cell-culture techniques, immunoinformatics and rational design of immunogens are driving the development of these novel concepts. Synthetic recombinant proteins comprising both B- and T-cell epitopes can be efficiently produced through modern biotechnology and bioprocessing methods, and can enable the induction of large repertoires of immune specificities. In particular, the inclusion of appropriate CD4+ T-cell epitopes is increasingly considered a key vaccine component to elicit robust immune responses, as suggested by results coming from HIV-1 clinical trials. In silico strategies for vaccine design are under active development to address genetic variation in pathogens and several broadly protective "universal" influenza and HIV-1 vaccines are currently at different stages of clinical trials. Other methods focus on improving population coverage in target populations by rationally considering specificity and prevalence of the HLA proteins, though a proof-of-concept in humans has not been demonstrated yet. Overall, we expect immunoinformatics and bioprocessing methods to become a central part of the next-generation epitope-based vaccine development and production process.
Evaluation of a Mobile Learning Organiser for University Students
ERIC Educational Resources Information Center
Corlett, Dan; Sharples, Mike; Bull, Susan; Chan, Tony
2005-01-01
This paper describes a 10-month trial of a mobile learning organiser, developed for use by university students. Implemented on a wireless-enabled Pocket PC hand-held computer, the organiser makes use of existing mobile applications as well as tools designed specifically for students to manage their learning. The trial set out to identify the…
ERIC Educational Resources Information Center
Smith-Lock, Karen M.; Leitão, Suze; Prior, Polly; Nickels, Lyndsey
2015-01-01
Purpose: This study compared the effectiveness of two grammar treatment procedures for children with specific language impairment. Method: A double-blind superiority trial with cluster randomization was used to compare a cueing procedure, designed to elicit a correct production following an initial error, to a recasting procedure, which required…
Conducting research in individual patients: lessons learnt from two series of N-of-1 trials
Wegman, Anke CM; van der Windt, Daniëlle AWM; Stalman, Wim AB; de Vries, Theo PGM
2006-01-01
Background Double-blind randomised N-of-1 trials (N-of-1 trials) may help with decisions concerning treatment when there is doubt regarding the effectiveness and suitability of medication for individual patients. The patient is his or her own control, and receives the experimental and the control treatment during several periods of time in random order. Reports of N-of-1 trials are still relatively scarce, and the research methodology is not as firmly established as that of RCTs. Recently, we have conducted two series of N-of-1 trials in general practice. Before, during, and after data-collection, difficulties regarding outcome assessment, analysis of the results, the withdrawal of patients, and the follow-up had to be dealt with. These difficulties are described and our solutions are discussed. Discussion To prevent or anticipate difficulties in N-of-1 trials, we argue that that it is important to individualise the outcome measures, and to carefully consider the objective, type of randomisation and the analysis. It is recommended to use the same dosages and dosage forms that the patient used before the trial, to start the trial with a run-in period, to formulate both general and individualised decision rules regarding the efficacy of treatment, to adjust treatment policies immediately after the trial, and to provide adequate instructions and support if treatment is adjusted. Summary Because of the specific characteristics of N-of-1 trials it is difficult to formulate general 'how to do it' guidelines for designing N-of-1 trials. However, when the design of each N-of-1 trial is tailored to the specific characteristics of each individual patient and the underlying medical problem, most difficulties in N-of-1 trials can be prevented or overcome. In this way, N-of-1 trials may be of help when deciding on drug treatment for individual patients. PMID:16984636
The Importance and Role of Intracluster Correlations in Planning Cluster Trials
Preisser, John S.; Reboussin, Beth A.; Song, Eun-Young; Wolfson, Mark
2008-01-01
There is increasing recognition of the critical role of intracluster correlations of health behavior outcomes in cluster intervention trials. This study examines the estimation, reporting, and use of intracluster correlations in planning cluster trials. We use an estimating equations approach to estimate the intracluster correlations corresponding to the multiple-time-point nested cross-sectional design. Sample size formulae incorporating 2 types of intracluster correlations are examined for the purpose of planning future trials. The traditional intracluster correlation is the correlation among individuals within the same community at a specific time point. A second type is the correlation among individuals within the same community at different time points. For a “time × condition” analysis of a pretest–posttest nested cross-sectional trial design, we show that statistical power considerations based upon a posttest-only design generally are not an adequate substitute for sample size calculations that incorporate both types of intracluster correlations. Estimation, reporting, and use of intracluster correlations are illustrated for several dichotomous measures related to underage drinking collected as part of a large nonrandomized trial to enforce underage drinking laws in the United States from 1998 to 2004. PMID:17879427
Keller, Martina; Gutjahr, Christoph; Möhring, Jens; Weis, Martin; Sökefeld, Markus; Gerhards, Roland
2014-02-01
Precision experimental design uses the natural heterogeneity of agricultural fields and combines sensor technology with linear mixed models to estimate the effect of weeds, soil properties and herbicide on yield. These estimates can be used to derive economic thresholds. Three field trials are presented using the precision experimental design in winter wheat. Weed densities were determined by manual sampling and bi-spectral cameras, yield and soil properties were mapped. Galium aparine, other broad-leaved weeds and Alopecurus myosuroides reduced yield by 17.5, 1.2 and 12.4 kg ha(-1) plant(-1) m(2) in one trial. The determined thresholds for site-specific weed control with independently applied herbicides were 4, 48 and 12 plants m(-2), respectively. Spring drought reduced yield effects of weeds considerably in one trial, since water became yield limiting. A negative herbicide effect on the crop was negligible, except in one trial, in which the herbicide mixture tended to reduce yield by 0.6 t ha(-1). Bi-spectral cameras for weed counting were of limited use and still need improvement. Nevertheless, large weed patches were correctly identified. The current paper presents a new approach to conducting field trials and deriving decision rules for weed control in farmers' fields. © 2013 Society of Chemical Industry.
Afolabi, Muhammed O; Adetifa, Jane U; Imoukhuede, Egeruan B; Viebig, Nicola K; Kampmann, Beate; Bojang, Kalifa
2014-05-01
Human immunodeficiency virus/acquired immune deficiency syndrome (HIV/AIDS) and malaria are among the most important infectious diseases in developing countries. Existing control strategies are unlikely to curtail these diseases in the absence of efficacious vaccines. Testing of HIV and malaria vaccines candidates start with early phase trials that are increasingly being conducted in developing countries where the burden of the diseases is high. Unique challenges, which affect planning and implementation of vaccine trials according to internationally accepted standards have thus been identified. In this review, we highlight specific challenges encountered during two early phase trials of novel HIV-1 and malaria vectored vaccine candidates conducted in The Gambia and how some of these issues were pragmatically addressed. We hope our experience will be useful for key study personnel involved in day-to-day running of similar clinical trials. It may also guide future design and implementation of vaccine trials in resource-constrained settings.
Bear, Danielle E; Wandrag, Liesl; Merriweather, Judith L; Connolly, Bronwen; Hart, Nicholas; Grocott, Michael P W
2017-08-26
The lack of benefit from randomised controlled trials has resulted in significant controversy regarding the role of nutrition during critical illness in terms of long-term recovery and outcome. Although methodological caveats with a failure to adequately appreciate biological mechanisms may explain these disappointing results, it must be acknowledged that nutritional support during early critical illness, when considered alone, may have limited long-term functional impact.This narrative review focuses specifically on recent clinical trials and evaluates the impact of nutrition during critical illness on long-term physical and functional recovery.Specific focus on the trial design and methodological limitations has been considered in detail. Limitations include delivery of caloric and protein targets, patient heterogeneity, short duration of intervention, inappropriate clinical outcomes and a disregard for baseline nutritional status and nutritional intake in the post-ICU period.With survivorship at the forefront of critical care research, it is imperative that nutrition studies carefully consider biological mechanisms and trial design because these factors can strongly influence outcomes, in particular long-term physical and functional outcome. Failure to do so may lead to inconclusive clinical trials and consequent rejection of the potentially beneficial effects of nutrition interventions during critical illness.
Machado, L A C; Kamper, S J; Herbert, R D; Maher, C G; McAuley, J H
2009-05-01
Estimates of treatment effects reported in placebo-controlled randomized trials are less subject to bias than those estimates provided by other study designs. The objective of this meta-analysis was to estimate the analgesic effects of treatments for non-specific low back pain reported in placebo-controlled randomized trials. Medline, Embase, Cinahl, PsychInfo and Cochrane Central Register of Controlled Trials databases were searched for eligible trials from earliest records to November 2006. Continuous pain outcomes were converted to a common 0-100 scale and pooled using a random effects model. A total of 76 trials reporting on 34 treatments were included. Fifty percent of the investigated treatments had statistically significant effects, but for most the effects were small or moderate: 47% had point estimates of effects of <10 points on the 100-point scale, 38% had point estimates from 10 to 20 points and 15% had point estimates of >20 points. Treatments reported to have large effects (>20 points) had been investigated only in a single trial. This meta-analysis revealed that the analgesic effects of many treatments for non-specific low back pain are small and that they do not differ in populations with acute or chronic symptoms.
2011-01-01
Background Low back disorders are a common and costly cause of pain and activity limitation in adults. Few treatment options have demonstrated clinically meaningful benefits apart from advice which is recommended in all international guidelines. Clinical heterogeneity of participants in clinical trials is hypothesised as reducing the likelihood of demonstrating treatment effects, and sampling of more homogenous subgroups is recommended. We propose five subgroups that allow the delivery of specific physiotherapy treatment targeting the pathoanatomical, neurophysiological and psychosocial components of low back disorders. The aim of this article is to describe the methodology of a randomised controlled trial comparing specific physiotherapy treatment to advice for people classified into five subacute low back disorder subgroups. Methods/Design A multi-centre parallel group randomised controlled trial is proposed. A minimum of 250 participants with subacute (6 weeks to 6 months) low back pain and/or referred leg pain will be classified into one of five subgroups and then randomly allocated to receive either physiotherapy advice (2 sessions over 10 weeks) or specific physiotherapy treatment (10 sessions over 10 weeks) tailored according to the subgroup of the participant. Outcomes will be assessed at 5 weeks, 10 weeks, 6 months and 12 months following randomisation. Primary outcomes will be activity limitation measured with a modified Oswestry Disability Index as well as leg and back pain intensity measured on separate 0-10 Numerical Rating Scales. Secondary outcomes will include a 7-point global rating of change scale, satisfaction with physiotherapy treatment, satisfaction with treatment results, the Sciatica Frequency and Bothersomeness Scale, quality of life (EuroQol-5D), interference with work, and psychosocial risk factors (Orebro Musculoskeletal Pain Questionnaire). Adverse events and co-interventions will also be measured. Data will be analysed according to intention to treat principles, using linear mixed models for continuous outcomes, Mann Whitney U tests for ordinal outcomes, and Chi-square, risk ratios and risk differences for dichotomous outcomes. Discussion This trial will determine the difference in outcomes between specific physiotherapy treatment tailored to each of the five subgroups versus advice which is recommended in guidelines as a suitable treatment for most people with a low back disorder. Trial registration Australia and New Zealand Clinical Trials Register (ANZCTR): ACTRN12609000834257. PMID:21599941
Wright, Chris; Heneghan, Nicola; Eveleigh, Gillian; Calvert, Melanie; Freemantle, Nick
2011-01-01
Objective To evaluate effectiveness of physiotherapy management in patients experiencing whiplash associated disorder II, on clinically relevant outcomes in the short and longer term. Design Systematic review and meta-analysis. Two reviewers independently searched information sources, assessed studies for inclusion, evaluated risk of bias and extracted data. A third reviewer mediated disagreement. Assessment of risk of bias was tabulated across included trials. Quantitative synthesis was conducted on comparable outcomes across trials with similar interventions. Meta-analyses compared effect sizes, with random effects as primary analyses. Data sources Predefined terms were employed to search electronic databases. Additional studies were identified from key journals, reference lists, authors and experts. Eligibility criteria for selecting studies Randomised controlled trials (RCTs) published in English before 31 December 2010 evaluating physiotherapy management of patients (>16 years), experiencing whiplash associated disorder II. Any physiotherapy intervention was included, when compared with other types of management, placebo/sham, or no intervention. Measurements reported on ≥1 outcome from the domains within the international classification of function, disability and health, were included. Results 21 RCTs (2126 participants, 9 countries) were included. Interventions were categorised as active physiotherapy or a specific physiotherapy intervention. 20/21 trials were evaluated as high risk of bias and one as unclear. 1395 participants were incorporated in the meta-analyses on 12 trials. In evaluating short term outcome in the acute/sub-acute stage, there was some evidence that active physiotherapy intervention reduces pain and improves range of movement, and that a specific physiotherapy intervention may reduce pain. However, moderate/considerable heterogeneity suggested that treatments may differ in nature or effect in different trial patients. Differences between participants, interventions and trial designs limited potential meta-analyses. Conclusions Inconclusive evidence exists for the effectiveness of physiotherapy management for whiplash associated disorder II. There is potential benefit for improving range of movement and pain short term through active physiotherapy, and for improving pain through a specific physiotherapy intervention. PMID:22102642
Tondorf, Theresa; Kaufmann, Lisa-Katrin; Degel, Alexander; Locher, Cosima; Birkhäuer, Johanna; Gerger, Heike; Ehlert, Ulrike
2017-01-01
Psychotherapy has been shown to be effective, but efforts to prove specific effects by placebo-controlled trials have been practically and conceptually hampered. We propose that adopting open/hidden designs from placebo research would offer a possible way to establish specificity in psychotherapy. Therefore, we tested the effects of providing opposing treatment rationales in an online expressive writing intervention on affect in healthy subjects. Results indicate that it was possible to conduct the expressive writing intervention both covertly and openly, but that participants in the hidden administration condition did not fully benefit from the otherwise effective expressive writing intervention in the long-run. Effect sizes between open and hidden administration groups were comparable to pre-post effect sizes of the intervention. While this finding is important for the understanding of psychotherapy's effects per se, it also proves that alternative research approaches to establish specificity are feasible and informative in psychotherapy research. Trial registration: German Clinical Trials Register DRKS00009428 PMID:29176768
Nicastro, Holly L.; Dunn, Barbara K.
2013-01-01
The Selenium and Vitamin E Cancer Prevention Trial (SELECT) was conducted to assess the efficacy of selenium and vitamin E alone, and in combination, on the incidence of prostate cancer. This randomized, double-blind, placebo-controlled, 2 × 2 factorial design clinical trial found that neither selenium nor vitamin E reduced the incidence of prostate cancer after seven years and that vitamin E was associated with a 17% increased risk of prostate cancer compared to placebo. The null result was surprising given the strong preclinical and clinical evidence suggesting chemopreventive activity of selenium. Potential explanations for the null findings include the agent formulation and dose, the characteristics of the cohort, and the study design. It is likely that only specific subpopulations may benefit from selenium supplementation; therefore, future studies should consider the baseline selenium status of the participants, age of the cohort, and genotype of specific selenoproteins, among other characteristics, in order to determine the activity of selenium in cancer prevention. PMID:23552052
Research methods to change clinical practice for patients with rare cancers.
Billingham, Lucinda; Malottki, Kinga; Steven, Neil
2016-02-01
Rare cancers are a growing group as a result of reclassification of common cancers by molecular markers. There is therefore an increasing need to identify methods to assess interventions that are sufficiently robust to potentially affect clinical practice in this setting. Methods advocated for clinical trials in rare diseases are not necessarily applicable in rare cancers. This Series paper describes research methods that are relevant for rare cancers in relation to the range of incidence levels. Strategies that maximise recruitment, minimise sample size, or maximise the usefulness of the evidence could enable the application of conventional clinical trial design to rare cancer populations. Alternative designs that address specific challenges for rare cancers with the aim of potentially changing clinical practice include Bayesian designs, uncontrolled n-of-1 trials, and umbrella and basket trials. Pragmatic solutions must be sought to enable some level of evidence-based health care for patients with rare cancers. Copyright © 2016 Elsevier Ltd. All rights reserved.
Attitudes of small animal practitioners toward participation in veterinary clinical trials
Gruen, Margaret E.; Griffith, Emily H.; Caney, Sarah M. A.; Rishniw, Mark; Lascelles, B. Duncan X.
2017-01-01
OBJECTIVE To determine attitudes of small animal practitioners toward veterinary clinical trials and variables influencing their likelihood of participating in such trials. DESIGN Cross-sectional survey. SAMPLE Small animal practitioners with membership in 1 of 2 online veterinary communities (n = 163 and 652). PROCEDURES An online survey was developed for each of 2 veterinary communities, and invitations to participate were sent via email. Each survey included questions designed to collect information on the respondents’ willingness to enroll their patients in clinical trials and to recommend participation to clients for their pets. RESULTS More than 80% of respondents to each survey indicated that they spend no time in clinical research. A high proportion of respondents were likely or extremely likely to recommend clinical trial participation to clients for their pets when those trials involved treatments licensed in other countries, novel treatments, respected investigators, or sponsoring by academic institutions, among other reasons. Reasons for not recommending participation included distance, time restrictions, and lack of awareness of ongoing clinical trials; 28% of respondents indicated that they did not usually learn about such clinical trials. Most respondents (79% to 92%) rated their recommendation of a trial as important to their client’s willingness to participate. CONCLUSIONS AND CLINICAL RELEVANCE Participation in veterinary clinical trials by small animal practitioners and their clients and patients appeared low. Efforts should be increased to raise practitioner awareness of clinical trials for which patients might qualify. Specific elements of trial design were identified that could be modified to increase participation. PMID:28001115
Assessing the Generalizability of Randomized Trial Results to Target Populations
Stuart, Elizabeth A.; Bradshaw, Catherine P.; Leaf, Philip J.
2014-01-01
Recent years have seen increasing interest in and attention to evidence-based practices, where the “evidence” generally comes from well-conducted randomized trials. However, while those trials yield accurate estimates of the effect of the intervention for the participants in the trial (known as “internal validity”), they do not always yield relevant information about the effects in a particular target population (known as “external validity”). This may be due to a lack of specification of a target population when designing the trial, difficulties recruiting a sample that is representative of a pre-specified target population, or to interest in considering a target population somewhat different from the population directly targeted by the trial. This paper first provides an overview of existing design and analysis methods for assessing and enhancing the ability of a randomized trial to estimate treatment effects in a target population. It then provides a case study using one particular method, which weights the subjects in a randomized trial to match the population on a set of observed characteristics. The case study uses data from a randomized trial of School-wide Positive Behavioral Interventions and Supports (PBIS); our interest is in generalizing the results to the state of Maryland. In the case of PBIS, after weighting, estimated effects in the target population were similar to those observed in the randomized trial. The paper illustrates that statistical methods can be used to assess and enhance the external validity of randomized trials, making the results more applicable to policy and clinical questions. However, there are also many open research questions; future research should focus on questions of treatment effect heterogeneity and further developing these methods for enhancing external validity. Researchers should think carefully about the external validity of randomized trials and be cautious about extrapolating results to specific populations unless they are confident of the similarity between the trial sample and that target population. PMID:25307417
Assessing the generalizability of randomized trial results to target populations.
Stuart, Elizabeth A; Bradshaw, Catherine P; Leaf, Philip J
2015-04-01
Recent years have seen increasing interest in and attention to evidence-based practices, where the "evidence" generally comes from well-conducted randomized trials. However, while those trials yield accurate estimates of the effect of the intervention for the participants in the trial (known as "internal validity"), they do not always yield relevant information about the effects in a particular target population (known as "external validity"). This may be due to a lack of specification of a target population when designing the trial, difficulties recruiting a sample that is representative of a prespecified target population, or to interest in considering a target population somewhat different from the population directly targeted by the trial. This paper first provides an overview of existing design and analysis methods for assessing and enhancing the ability of a randomized trial to estimate treatment effects in a target population. It then provides a case study using one particular method, which weights the subjects in a randomized trial to match the population on a set of observed characteristics. The case study uses data from a randomized trial of school-wide positive behavioral interventions and supports (PBIS); our interest is in generalizing the results to the state of Maryland. In the case of PBIS, after weighting, estimated effects in the target population were similar to those observed in the randomized trial. The paper illustrates that statistical methods can be used to assess and enhance the external validity of randomized trials, making the results more applicable to policy and clinical questions. However, there are also many open research questions; future research should focus on questions of treatment effect heterogeneity and further developing these methods for enhancing external validity. Researchers should think carefully about the external validity of randomized trials and be cautious about extrapolating results to specific populations unless they are confident of the similarity between the trial sample and that target population.
Cepeda, M Soledad; Lobanov, Victor; Berlin, Jesse A
2013-04-01
ClinicalTrials.gov is a registry and results database of federally and privately supported clinical trials conducted worldwide. We sought to answer: what are the characteristics of pain trials; how frequently are these trials stopped and why; what is the magnitude of attrition due to lack of efficacy or adverse events; and whether the withdrawal rates depend on pain syndrome. To facilitate this and subsequent studies, we have developed a system called Sherlock that automatically downloads data from ClinicalTrials.gov into a relational database. We included pain interventional trials. To evaluate attrition, we restricted consideration to prospective randomized, parallel, double-blind, placebo-controlled trials. Of the 82,867 trials, 6% reported results and 5.6% terminated before the planned number of subjects was accrued. Of these early terminations, 38% were due to enrollment difficulties. In the placebo arms, 3.8% of participants withdrew due to lack of efficacy and 4.9% due to adverse events, with proportions differing among pain conditions. Compared with migraine trials, in fibromyalgia trials 5.1% more participants withdrew due to lack of efficacy (95% confidence interval [CI], 2.5-7.8%), and 6.4% more withdrew due to adverse events (95% CI, 4.3-8.6%). Nonsteroidal anti-inflammatory drugs were the treatment class with the lowest adverse events withdrawals. Recruitment challenges account for the largest proportion of noncompleted trials. Attrition rates differ across pain conditions. Migraine studies had the lowest withdrawal rate. Tools like Sherlock facilitate conducting research in the ClinicalTrials.gov registry. ClinicalTrials.gov registry enables researchers to get a snapshot of a specific field and observe changes over time in trial design, including numbers of subjects accrued, and it can inform clinical trial design. We learned that recruitment challenges account for the largest proportion of noncompleted trials, attrition rates differed across pain conditions, and migraine studies had the lowest withdrawal rate. Copyright © 2013 American Pain Society. Published by Elsevier Inc. All rights reserved.
Research design considerations for chronic pain prevention clinical trials: IMMPACT recommendations
Gewandter, Jennifer S.; Dworkin, Robert H.; Turk, Dennis C.; Farrar, John T.; Fillingim, Roger B.; Gilron, Ian; Markman, John D.; Oaklander, Anne Louise; Polydefkis, Michael J.; Raja, Srinivasa N.; Robinson, James P.; Woolf, Clifford J.; Ziegler, Dan; Ashburn, Michael A.; Burke, Laurie B.; Cowan, Penney; George, Steven Z.; Goli, Veeraindar; Graff, Ole X.; Iyengar, Smriti; Jay, Gary W.; Katz, Joel; Kehlet, Henrik; Kitt, Rachel A.; Kopecky, Ernest A.; Malamut, Richard; McDermott, Michael P.; Palmer, Pamela; Rappaport, Bob A.; Rauschkolb, Christine; Steigerwald, Ilona; Tobias, Jeffrey; Walco, Gary A.
2018-01-01
Although certain risk factors can identify individuals who are most likely to develop chronic pain, few interventions to prevent chronic pain have been identified. To facilitate the identification of preventive interventions, an IMMPACT meeting was convened to discuss research design considerations for clinical trials investigating the prevention of chronic pain. We present general design considerations for prevention trials in populations that are at relatively high risk for developing chronic pain. Specific design considerations included subject identification, timing and duration of treatment, outcomes, timing of assessment, and adjusting for risk factors in the analyses. We provide a detailed examination of 4 models of chronic pain prevention (i.e., chronic post-surgical pain, postherpetic neuralgia, chronic low back pain, and painful chemotherapy-induced peripheral neuropathy). The issues discussed can, in many instances, be extrapolated to other chronic pain conditions. These examples were selected because they are representative models of primary and secondary prevention, reflect persistent pain resulting from multiple insults (i.e., surgery, viral infection, injury, and toxic/noxious element exposure), and are chronically painful conditions that are treated with a range of interventions. Improvements in the design of chronic pain prevention trials could improve assay sensitivity and thus accelerate the identification of efficacious interventions. Such interventions would have the potential to reduce the prevalence of chronic pain in the population. Additionally, standardization of outcomes in prevention clinical trials will facilitate meta-analyses and systematic reviews and improve detection of preventive strategies emerging from clinical trials. PMID:25887465
Research design considerations for chronic pain prevention clinical trials: IMMPACT recommendations.
Gewandter, Jennifer S; Dworkin, Robert H; Turk, Dennis C; Farrar, John T; Fillingim, Roger B; Gilron, Ian; Markman, John D; Oaklander, Anne Louise; Polydefkis, Michael J; Raja, Srinivasa N; Robinson, James P; Woolf, Clifford J; Ziegler, Dan; Ashburn, Michael A; Burke, Laurie B; Cowan, Penney; George, Steven Z; Goli, Veeraindar; Graff, Ole X; Iyengar, Smriti; Jay, Gary W; Katz, Joel; Kehlet, Henrik; Kitt, Rachel A; Kopecky, Ernest A; Malamut, Richard; McDermott, Michael P; Palmer, Pamela; Rappaport, Bob A; Rauschkolb, Christine; Steigerwald, Ilona; Tobias, Jeffrey; Walco, Gary A
2015-07-01
Although certain risk factors can identify individuals who are most likely to develop chronic pain, few interventions to prevent chronic pain have been identified. To facilitate the identification of preventive interventions, an IMMPACT meeting was convened to discuss research design considerations for clinical trials investigating the prevention of chronic pain. We present general design considerations for prevention trials in populations that are at relatively high risk for developing chronic pain. Specific design considerations included subject identification, timing and duration of treatment, outcomes, timing of assessment, and adjusting for risk factors in the analyses. We provide a detailed examination of 4 models of chronic pain prevention (ie, chronic postsurgical pain, postherpetic neuralgia, chronic low back pain, and painful chemotherapy-induced peripheral neuropathy). The issues discussed can, in many instances, be extrapolated to other chronic pain conditions. These examples were selected because they are representative models of primary and secondary prevention, reflect persistent pain resulting from multiple insults (ie, surgery, viral infection, injury, and toxic or noxious element exposure), and are chronically painful conditions that are treated with a range of interventions. Improvements in the design of chronic pain prevention trials could improve assay sensitivity and thus accelerate the identification of efficacious interventions. Such interventions would have the potential to reduce the prevalence of chronic pain in the population. Additionally, standardization of outcomes in prevention clinical trials will facilitate meta-analyses and systematic reviews and improve detection of preventive strategies emerging from clinical trials.
González-Ortega, Itxaso; Echeburúa, Enrique; García-Alocén, Adriana; Vega, Patricia; González-Pinto, Ana
2016-07-29
The high rate of cannabis use among patients with first-episode psychosis (FEP), as well as the associated negative impact on illness course and treatment outcomes, underlines the need for effective interventions in these populations. However, to date, there have been few clinical treatment trials (of pharmacological or psychological interventions) that have specifically focused on addressing comorbid cannabis use among these patients. The aim of this paper is to describe the design of a study protocol for a randomized controlled trial in which the objective is to assess the efficacy of a specific cognitive behavioral therapy program for cannabis cessation in patients with FEP compared to standard treatment (psychoeducation). This is a single-blind randomized study with 1 year of follow-up. Patients are to be randomly assigned to one of two treatments: (1) specific cognitive behavioral therapy for cannabis cessation composed of 1-hour sessions once a week for 16 weeks, in addition to pharmacological treatment scheduled by the psychiatrist, or (2) a control group (psychoeducation + pharmacological treatment) following the same format as the experimental group. Participants in both groups will be evaluated at baseline (pre-treatment), at 16 weeks (post-treatment), and at 3 and 6 months and 1 year of follow-up. The primary outcome will be that patients in the experimental group will have greater cannabis cessation than patients in the control group at post-treatment. The secondary outcome will be that the experimental group will have better clinical and functional outcomes than the control group. This study provides the description of a clinical trial design based on specific cognitive behavioral therapy for cannabis cessation in FEP patients, aiming to improve clinical and functional outcome, as well as tackling the addictive disorder. NCT02319746 ClinicalTrials.gov Identifier. ClinicalTrials.gov Protocol and Results Registration System (PRS) Receipt Release Date: 15 December 2014.
Coffey, Christopher S; Levin, Bruce; Clark, Christina; Timmerman, Cate; Wittes, Janet; Gilbert, Peter; Harris, Sara
2012-12-01
The clinical trials community has a never-ending search for dependable and reliable ways to improve clinical research. This exploration has led to considerable interest in adaptive clinical trial designs, which provide the flexibility to adjust trial characteristics on the basis of data reviewed at interim stages. Statisticians and clinical investigators have proposed or implemented a wide variety of adaptations in clinical trials, but specific approaches have met with differing levels of support. Within industry, investigators are actively exploring the benefits and pitfalls associated with adaptive designs (ADs). For example, a Drug Information Association (DIA) working group on ADs has engaged regulatory agencies in discussions. Many researchers working on publicly funded clinical trials, however, are not yet fully engaged in this discussion. We organized the Scientific Advances in Adaptive Clinical Trial Designs Workshop to begin a conversation about using ADs in publicly funded research. Held in November of 2009, the 1½-day workshop brought together representatives from the National Institutes of Health (NIH), the Food and Drug Administration (FDA), the European Medicines Agency (EMA), the pharmaceutical industry, nonprofit foundations, the patient advocacy community, and academia. The workshop offered a forum for participants to address issues of ADs that arise at the planning, designing, and execution stages of clinical trials, and to hear the perspectives of influential members of the clinical trials community. The participants also set forth recommendations for guiding action to promote the appropriate use of ADs. These recommendations have since been presented, discussed, and vetted in a number of venues including the University of Pennsylvania Conference on Statistical Issues in Clinical Trials and the Society for Clinical Trials annual meeting. To provide a brief overview of ADs, describe the rationale behind conducting the workshop, and summarize the main recommendations that were produced as a result of this workshop. There is a growing interest in the use of adaptive clinical trial designs. However, a number of logistical barriers need to be addressed in order to obtain the potential advantages of an AD. Currently, the pharmaceutical industry is well ahead of academic trialists with respect to addressing these barriers. Academic trialists will need to address important issues such as education, infrastructure, modifications to existing funding models, and the impact on Data and Safety Monitoring Boards (DSMB) in order to achieve the possible benefits of adaptive clinical trial designs.
Erkan, Doruk; Aguiar, Cassyanne L; Andrade, Danieli; Cohen, Hannah; Cuadrado, Maria J; Danowski, Adriana; Levy, Roger A; Ortel, Thomas L; Rahman, Anisur; Salmon, Jane E; Tektonidou, Maria G; Willis, Rohan; Lockshin, Michael D
2014-06-01
Antiphospholipid Syndrome (APS) is characterized by vascular thrombosis and/or pregnancy morbidity occurring in patients with persistent antiphospholipid antibodies (aPL). The primary objective of the APS Treatment Trends Task Force, created as part of the 14th International Congress on aPL, was to systematically review the potential future treatment strategies for aPL-positive patients. The task force chose as future clinical research directions: a) determining the necessity for controlled clinical trials in venous thromboembolism with the new oral direct thrombin or anti-factor Xa inhibitors pending the results of the ongoing rivaroxaban in APS (RAPS) trial, and designing controlled clinical trials in other forms of thrombotic APS; b) systematically analyzing the literature as well as aPL/APS registries, and creating specific registries for non-warfarin/heparin anticoagulants; c) increasing recruitment for an ongoing primary thrombosis prevention trial, and designing secondary thrombosis and pregnancy morbidity prevention trials with hydroxychloroquine; d) determining surrogate markers to select patients for statin trials; e) designing controlled studies with rituximab and other anti-B-cell agents; f) designing mechanistic and clinical studies with eculizumab and other complement inhibitors; and g) chemically modifying peptide therapy to improve the half-life and minimize immunogenicity. The report also includes recommendations for clinicians who consider using these agents in difficult-to-manage aPL-positive patients. Copyright © 2014 Elsevier B.V. All rights reserved.
[Medical nutrition in Alzheimer's: the trials].
Scheltens, Philip; Twisk, Jos W R
2013-01-01
We describe the small but statistically significant effects of the medical nutrition diet 'Souvenaid' on memory in early Alzheimer's disease in two published randomised clinical trials. We specifically discuss the design and statistical approach, which were predefined and meet current standards in the field. Further research is needed to substantiate the long term effects and learn more about the mode of action of Souvenaid.
2012-01-01
Background The provision of appropriate medical and nursing care for people with dementia is a major challenge for the healthcare system in Germany. New models of healthcare provision need to be developed, tested and implemented on the population level. Trials in which collaborative care for dementia in the primary care setting were studied have demonstrated its effectiveness. These studies have been conducted in different healthcare systems, however, so it is unclear whether these results extend to the specific context of the German healthcare system. The objective of this population-based intervention trial in the primary care setting is to test the efficacy and efficiency of implementing a subsidiary support system on a population level for persons with dementia who live at home. Methods and study design The study was designed to assemble a general physician-based epidemiological cohort of people above the age of 70 who live at home (DelpHi cohort). These people are screened for eligibility to participate in a trial of dementia care management (DelpHi trial). The trial is a cluster-randomised, controlled intervention trial with two arms (intervention and control) designed to test the efficacy and efficiency of implementing a subsidiary support system for persons with dementia who live at home. This subsidiary support system is initiated and coordinated by a dementia care manager: a nurse with dementia-specific qualifications who delivers the intervention according to a systematic, detailed protocol. The primary outcome is quality of life and healthcare for patients with dementia and their caregivers. This is a multidimensional outcome with a focus on four dimensions: (1) quality of life, (2) caregiver burden, (3) behavioural and psychological symptoms of dementia and (4) pharmacotherapy with an antidementia drug and prevention or suspension of potentially inappropriate medication. Secondary outcomes include the assessment of dementia syndromes, activities of daily living, social support health status, utilisation of health care resources and medication. Discussion The results will provide evidence for specific needs in ambulatory care for persons with dementia and will show effective ways to meet those needs. Qualification requirements will be evaluated, and the results will help to modify existing guidelines and treatment paths. Trial registration NCT01401582 PMID:22575023
Bekelman, Justin E.; Deye, James A.; Vikram, Bhadrasain; Bentzen, Soren M.; Bruner, Deborah; Curran, Walter J.; Dignam, James; Efstathiou, Jason A.; FitzGerald, T. J.; Hurkmans, Coen; Ibbott, Geoffrey S.; Lee, J. Jack; Merchant, Timothy E.; Michalski, Jeff; Palta, Jatinder R.; Simon, Richard; Ten Haken, Randal K.; Timmerman, Robert; Tunis, Sean; Coleman, C. Norman; Purdy, James
2012-01-01
Background In the context of national calls for reorganizing cancer clinical trials, the National Cancer Institute (NCI) sponsored a two day workshop to examine the challenges and opportunities for optimizing radiotherapy quality assurance (QA) in clinical trial design. Methods Participants reviewed the current processes of clinical trial QA and noted the QA challenges presented by advanced technologies. Lessons learned from the radiotherapy QA programs of recent trials were discussed in detail. Four potential opportunities for optimizing radiotherapy QA were explored, including the use of normal tissue toxicity and tumor control metrics, biomarkers of radiation toxicity, new radiotherapy modalities like proton beam therapy, and the international harmonization of clinical trial QA. Results Four recommendations were made: 1) Develop a tiered (and more efficient) system for radiotherapy QA and tailor intensity of QA to clinical trial objectives. Tiers include (i) general credentialing, (ii) trial specific credentialing, and (iii) individual case review; 2) Establish a case QA repository; 3) Develop an evidence base for clinical trial QA and introduce innovative prospective trial designs to evaluate radiotherapy QA in clinical trials; and 4) Explore the feasibility of consolidating clinical trial QA in the United States. Conclusion Radiotherapy QA may impact clinical trial accrual, cost, outcomes and generalizability. To achieve maximum benefit, QA programs must become more efficient and evidence-based. PMID:22425219
Bekelman, David B; Plomondon, Mary E; Sullivan, Mark D; Nelson, Karin; Hattler, Brack; McBryde, Connor; Lehmann, Kenneth G; Potfay, Jonathan; Heidenreich, Paul; Rumsfeld, John S
2013-07-09
Chronic heart failure (HF) disease management programs have reported inconsistent results and have not included comorbid depression management or specifically focused on improving patient-reported outcomes. The Patient Centered Disease Management (PCDM) trial was designed to test the effectiveness of collaborative care disease management in improving health status (symptoms, functioning, and quality of life) in patients with HF who reported poor HF-specific health status. Patients with a HF diagnosis at four VA Medical Centers were identified through population-based sampling. Patients with a Kansas City Cardiomyopathy Questionnaire (KCCQ, a measure of HF-specific health status) score of < 60 (heavy symptom burden and impaired quality of life) were invited to enroll in the PCDM trial. Enrolled patients were randomized to receive usual care or the PCDM intervention, which included: (1) collaborative care management by VA clinicians including a nurse, cardiologist, internist, and psychiatrist, who worked with patients and their primary care providers to provide guideline-concordant care management, (2) home telemonitoring and guided patient self-management support, and (3) screening and treatment for comorbid depression. The primary study outcome is change in overall KCCQ score. Secondary outcomes include depression, medication adherence, guideline-based care, hospitalizations, and mortality. The PCDM trial builds on previous studies of HF disease management by prioritizing patient health status, implementing a collaborative care model of health care delivery, and addressing depression, a key barrier to optimal disease management. The study has been designed as an 'effectiveness trial' to support broader implementation in the healthcare system if it is successful. Unique identifier: NCT00461513.
Senni, Michele; Paulus, Walter J.; Gavazzi, Antonello; Fraser, Alan G.; Díez, Javier; Solomon, Scott D.; Smiseth, Otto A.; Guazzi, Marco; Lam, Carolyn S. P.; Maggioni, Aldo P.; Tschöpe, Carsten; Metra, Marco; Hummel, Scott L.; Edelmann, Frank; Ambrosio, Giuseppe; Stewart Coats, Andrew J.; Filippatos, Gerasimos S.; Gheorghiade, Mihai; Anker, Stefan D.; Levy, Daniel; Pfeffer, Marc A.; Stough, Wendy Gattis; Pieske, Burkert M.
2014-01-01
The management of heart failure with reduced ejection fraction (HF-REF) has improved significantly over the last two decades. In contrast, little or no progress has been made in identifying evidence-based, effective treatments for heart failure with preserved ejection fraction (HF-PEF). Despite the high prevalence, mortality, and cost of HF-PEF, large phase III international clinical trials investigating interventions to improve outcomes in HF-PEF have yielded disappointing results. Therefore, treatment of HF-PEF remains largely empiric, and almost no acknowledged standards exist. There is no single explanation for the negative results of past HF-PEF trials. Potential contributors include an incomplete understanding of HF-PEF pathophysiology, the heterogeneity of the patient population, inadequate diagnostic criteria, recruitment of patients without true heart failure or at early stages of the syndrome, poor matching of therapeutic mechanisms and primary pathophysiological processes, suboptimal study designs, or inadequate statistical power. Many novel agents are in various stages of research and development for potential use in patients with HF-PEF. To maximize the likelihood of identifying effective therapeutics for HF-PEF, lessons learned from the past decade of research should be applied to the design, conduct, and interpretation of future trials. This paper represents a synthesis of a workshop held in Bergamo, Italy, and it examines new and emerging therapies in the context of specific, targeted HF-PEF phenotypes where positive clinical benefit may be detected in clinical trials. Specific considerations related to patient and endpoint selection for future clinical trials design are also discussed. PMID:25104786
Methodological issues with adaptation of clinical trial design.
Hung, H M James; Wang, Sue-Jane; O'Neill, Robert T
2006-01-01
Adaptation of clinical trial design generates many issues that have not been resolved for practical applications, though statistical methodology has advanced greatly. This paper focuses on some methodological issues. In one type of adaptation such as sample size re-estimation, only the postulated value of a parameter for planning the trial size may be altered. In another type, the originally intended hypothesis for testing may be modified using the internal data accumulated at an interim time of the trial, such as changing the primary endpoint and dropping a treatment arm. For sample size re-estimation, we make a contrast between an adaptive test weighting the two-stage test statistics with the statistical information given by the original design and the original sample mean test with a properly corrected critical value. We point out the difficulty in planning a confirmatory trial based on the crude information generated by exploratory trials. In regards to selecting a primary endpoint, we argue that the selection process that allows switching from one endpoint to the other with the internal data of the trial is not very likely to gain a power advantage over the simple process of selecting one from the two endpoints by testing them with an equal split of alpha (Bonferroni adjustment). For dropping a treatment arm, distributing the remaining sample size of the discontinued arm to other treatment arms can substantially improve the statistical power of identifying a superior treatment arm in the design. A common difficult methodological issue is that of how to select an adaptation rule in the trial planning stage. Pre-specification of the adaptation rule is important for the practicality consideration. Changing the originally intended hypothesis for testing with the internal data generates great concerns to clinical trial researchers.
Mitry, Danny; Peto, Tunde; Hayat, Shabina; Blows, Peter; Morgan, James; Khaw, Kay-Tee; Foster, Paul J
2015-01-01
Crowdsourcing is the process of simplifying and outsourcing numerous tasks to many untrained individuals. Our aim was to assess the performance and repeatability of crowdsourcing in the classification of normal and glaucomatous discs from optic disc images. Optic disc images (N = 127) with pre-determined disease status were selected by consensus agreement from grading experts from a large cohort study. After reading brief illustrative instructions, we requested that knowledge workers (KWs) from a crowdsourcing platform (Amazon MTurk) classified each image as normal or abnormal. Each image was classified 20 times by different KWs. Two study designs were examined to assess the effect of varying KW experience and both study designs were conducted twice for consistency. Performance was assessed by comparing the sensitivity, specificity and area under the receiver operating characteristic curve (AUC). Overall, 2,540 classifications were received in under 24 hours at minimal cost. The sensitivity ranged between 83-88% across both trials and study designs, however the specificity was poor, ranging between 35-43%. In trial 1, the highest AUC (95%CI) was 0.64(0.62-0.66) and in trial 2 it was 0.63(0.61-0.65). There were no significant differences between study design or trials conducted. Crowdsourcing represents a cost-effective method of image analysis which demonstrates good repeatability and a high sensitivity. Optimisation of variables such as reward schemes, mode of image presentation, expanded response options and incorporation of training modules should be examined to determine their effect on the accuracy and reliability of this technique in retinal image analysis.
A systematic review of studies of web portals for patients with diabetes mellitus.
Coughlin, Steven S; Williams, Lovoria B; Hatzigeorgiou, Christos
2017-01-01
Patient web portals are password-protected online websites that offer patients 24-hour access to personal health information from anywhere with an Internet connection. Due to advances in health information technologies, there has been increasing interest among providers and researchers in patient web portals for use by patients with diabetes and other chronic conditions. This article, which is based upon bibliographic searches in PubMed, reviews web portals for patients with diabetes mellitus including patient web portals tethered to electronic medical records and web portals developed specifically for patients with diabetes. Twelve studies of the impact of patient web portals on the management of diabetes patients were identified. Three had a cross-sectional design, 1 employed mixed-methods, one had a matched-control design, 3 had a retrospective cohort design, and 5 were randomized controlled trials. Six (50%) of the studies examined web portals tethered to electronic medical records and the remainder were web portals developed specifically for diabetes patients. The results of this review suggest that secure messaging between adult diabetic patients and their clinician is associated with improved glycemic control. However, results from observational studies indicate that many diabetic patients do not take advantage of web portal features such as secure messaging, perhaps because of a lack of internet access or lack of experience in navigating web portal resources. Although results from randomized controlled trials provide stronger evidence of the efficacy of web portal use in improving glycemic control among diabetic patients, the number of trials is small and results from the trials have been mixed. Studies suggest that secure messaging between adult diabetic patients and their clinician is associated with improved glycemic control, but negative findings have also been reported. The number of randomized controlled trials that have examined the efficacy of web portal use in improving glycemic control among diabetic patients is still small. Additional research is needed to identify specific portal features that may impact quality of care or improve glycemic control.
A systematic review of studies of web portals for patients with diabetes mellitus
Williams, Lovoria B.; Hatzigeorgiou, Christos
2017-01-01
Patient web portals are password-protected online websites that offer patients 24-hour access to personal health information from anywhere with an Internet connection. Due to advances in health information technologies, there has been increasing interest among providers and researchers in patient web portals for use by patients with diabetes and other chronic conditions. This article, which is based upon bibliographic searches in PubMed, reviews web portals for patients with diabetes mellitus including patient web portals tethered to electronic medical records and web portals developed specifically for patients with diabetes. Twelve studies of the impact of patient web portals on the management of diabetes patients were identified. Three had a cross-sectional design, 1 employed mixed-methods, one had a matched-control design, 3 had a retrospective cohort design, and 5 were randomized controlled trials. Six (50%) of the studies examined web portals tethered to electronic medical records and the remainder were web portals developed specifically for diabetes patients. The results of this review suggest that secure messaging between adult diabetic patients and their clinician is associated with improved glycemic control. However, results from observational studies indicate that many diabetic patients do not take advantage of web portal features such as secure messaging, perhaps because of a lack of internet access or lack of experience in navigating web portal resources. Although results from randomized controlled trials provide stronger evidence of the efficacy of web portal use in improving glycemic control among diabetic patients, the number of trials is small and results from the trials have been mixed. Studies suggest that secure messaging between adult diabetic patients and their clinician is associated with improved glycemic control, but negative findings have also been reported. The number of randomized controlled trials that have examined the efficacy of web portal use in improving glycemic control among diabetic patients is still small. Additional research is needed to identify specific portal features that may impact quality of care or improve glycemic control. PMID:28736732
Johnson, Liza-Marie; Leek, Angela C.; Drotar, Dennis; Noll, Robert B.; Rheingold, Susan R.; Kodish, Eric D.; Baker, Justin N.
2015-01-01
Background It can be difficult to explain pediatric Phase I oncology trials to families of children with refractory cancer. Parents may misunderstand the information presented to them, and physicians may assume that certain topics are covered in the informed consent document and need not be discussed. Communication models can help to ensure effective discussions. Methods Suggestions for improving the informed consent process were first solicited from Phase I study clinicians via questionnaire. Eight parents who had enrolled their child on a Phase I pediatric oncology trial were recruited for an advisory group designed to assess the clinicians’ suggestions and make additional recommendations for improving informed consent for pediatric Phase I trials. Results A Phase I Communication Model was designed to incorporate the suggestions of clinicians and families. It focuses on education of parents/families about Phase I trials at specific time points during a child’s illness, but specifically at the point of relapse. We also present an informative Phase I fact sheet that can be distributed to families. Conclusions Families who will be offered information about a Phase I clinical trial can first receive a standardized fact sheet explaining the general purpose of these early-phase clinical trials. Parental understanding may be further enhanced when oncologists address key themes, beginning at diagnosis and continuing through important decision points during the child’s illness. This model should be prospectively evaluated. PMID:25873253
Obtaining the Optimal Dose in Alcohol Dependence Studies
Wages, Nolan A.; Liu, Lei; O’Quigley, John; Johnson, Bankole A.
2012-01-01
In alcohol dependence studies, the treatment effect at different dose levels remains to be ascertained. Establishing this effect would aid us in identifying the best dose that has satisfactory efficacy while minimizing the rate of adverse events. We advocate the use of dose-finding methodology that has been successfully implemented in the cancer and HIV settings to identify the optimal dose in a cost-effective way. Specifically, we describe the continual reassessment method (CRM), an adaptive design proposed for cancer trials to reconcile the needs of dose-finding experiments with the ethical demands of established medical practice. We are applying adaptive designs for identifying the optimal dose of medications for the first time in the context of pharmacotherapy research in alcoholism. We provide an example of a topiramate trial as an illustration of how adaptive designs can be used to locate the optimal dose in alcohol treatment trials. It is believed that the introduction of adaptive design methods will enable the development of medications for the treatment of alcohol dependence to be accelerated. PMID:23189064
Code of Federal Regulations, 2012 CFR
2012-07-01
..., the design and operating information required by § 270.66 must be provided for both the similar device and the device to which the data is to be applied, and a comparison of the design and operating... provided to support the contention that a trial burn is not needed; (B) The design and operating conditions...
Code of Federal Regulations, 2013 CFR
2013-07-01
..., the design and operating information required by § 270.66 must be provided for both the similar device and the device to which the data is to be applied, and a comparison of the design and operating... provided to support the contention that a trial burn is not needed; (B) The design and operating conditions...
Code of Federal Regulations, 2014 CFR
2014-07-01
..., the design and operating information required by § 270.66 must be provided for both the similar device and the device to which the data is to be applied, and a comparison of the design and operating... provided to support the contention that a trial burn is not needed; (B) The design and operating conditions...
Code of Federal Regulations, 2011 CFR
2011-07-01
..., the design and operating information required by § 270.66 must be provided for both the similar device and the device to which the data is to be applied, and a comparison of the design and operating... provided to support the contention that a trial burn is not needed; (B) The design and operating conditions...
Code of Federal Regulations, 2010 CFR
2010-07-01
..., the design and operating information required by § 270.66 must be provided for both the similar device and the device to which the data is to be applied, and a comparison of the design and operating... provided to support the contention that a trial burn is not needed; (B) The design and operating conditions...
Greenfield, Shelly F; Rosa, Carmen; Putnins, Susan I; Green, Carla A; Brooks, Audrey J; Calsyn, Donald A; Cohen, Lisa R; Erickson, Sarah; Gordon, Susan M; Haynes, Louise; Killeen, Therese; Miele, Gloria; Tross, Susan; Winhusen, Theresa
2011-09-01
The National Institute of Drug Abuse's National Drug Abuse Treatment Clinical Trials Network (CTN) was established to foster translation of research into practice in substance abuse treatment settings. The CTN provides a unique opportunity to examine in multi-site, translational clinical trials, the outcomes of treatment interventions targeting vulnerable subgroups of women; the comparative effectiveness of gender-specific protocols to reduce risk behaviors; and gender differences in clinical outcomes. To review gender-related findings from published CTN clinical trials and related studies from January 2000 to March 2010. CTN studies were selected for review if they focused on treatment outcomes or services for special populations of women with substance use disorders (SUDs) including those with trauma histories, pregnancy, co-occurring eating and other psychiatric disorders, and HIV risk behaviors; or implemented gender-specific protocols. The CTN has randomized 11,500 participants (41% women) across 200 clinics in 24 randomized controlled trials in community settings, of which 4 have been gender-specific. This article summarizes gender-related findings from CTN clinical trials and related studies, focusing on trauma histories, pregnancy, co-occurring eating and other psychiatric disorders, and HIV risk behaviors. These published studies have expanded the evidence base regarding interventions for vulnerable groups of women with SUDs as well as gender-specific interventions to reduce HIV risk behaviors in substance-using men and women. The results also underscore the complexity of accounting for gender in the design of clinical trials and analysis of results. To fully understand the relevance of gender-specific moderators and mediators of outcome, it is essential that future translational studies adopt more sophisticated approaches to understanding and measuring gender-relevant factors and plan sample sizes that are adequate to support more nuanced analytic methods.
Hartzler, Bryan; Peavy, K Michelle; Jackson, T Ron; Carney, Molly
2016-01-22
Pragmatic trials of empirically-supported behavior therapies may inform clinical and policy decisions concerning therapy sustainment. This retrospective trial design paper describes and discusses pragmatic features of a hybrid type III implementation/effectiveness trial of a contingency management (CM) intervention at an opioid treatment program. Prior reporting (Hartzler et al., J Subst Abuse Treat 46:429-438, 2014; Hartzler, Subst Abuse Treat Prev Policy 10:30, 2015) notes success in recruiting program staff for voluntary participation, durable impacts of CM training on staff-level outcomes, provisional setting implementation of the intervention, documentation of clinical effectiveness, and post-trial sustainment of CM. Six pragmatic design features, and both scientific and practical bases for their inclusion in the trial, are presented: (1) a collaborative intervention design process, (2) voluntary recruitment of program staff for therapy training and implementation, (3) serial training outcome assessments, with quasi-experimental staff randomization to either single or multiple baseline assessment conditions, (4) designation of a 90-day period immediately after training in which the setting implemented the intervention on a provisional basis, (5) inclusive patient eligibility for receipt of the CM intervention, and (6) designation of two staff as local implementation leaders to oversee clinical/administrative issues in provisional implementation. Each pragmatic trial design feature is argued to have contributed to sustainment of CM. Contributions implicate the building of setting proprietorship for the CM intervention, culling of internal staff expertise in its delivery, iterative use of assessment methods that limited setting burden, documentation of setting-specific clinical effectiveness, expanded penetration of CM among staff during provisional implementation, and promotion of setting self-reliance in the oversight of sustainable implementation procedures. It is hoped this discussion offers ideas for how to impact local clinical and policy decisions via effective behavior therapy dissemination.
Jaspan, Heather B; Cunningham, Coleen K; Tucker, Tim J P; Wright, Peter F; Self, Steve G; Sheets, Rebecca L; Rogers, Audrey S; Bekker, Linda-Gail; Wilson, Craig M; Duerr, Ann; Wasserheit, Judith N
2008-01-01
The search for a safe effective HIV vaccine has been a centerpiece of HIV research for almost 2 decades. More than 60 clinical HIV vaccine trials have been conducted to date. Several promising candidate HIV vaccines are in advanced clinical development. To date, however, no trial has included adolescents, one of the most important target groups for any preventive HIV vaccine. To license a vaccine for use in this age group, efficacy data or, at a minimum, bridging safety and immunogenicity data in this population are needed. To accomplish this, several critical issues and special challenges in the development and implementation of HIV vaccine trials in adolescents must be addressed, including regulatory considerations, potential differentials in safety and immunogenicity, alternative trial design strategies, recruitment and retention challenges, community involvement models, and approaches to informed consent/assent. This article examines these issues and proposes specific next steps to facilitate the routine inclusion of this high-priority population in preventive HIV vaccine trials as early and seamlessly as possible.
Kraemer, Helena C.; Epstein, Robert S.; Frank, Ellen; Haynes, Ginger; Laughren, Thomas P.; Mcnulty, James; Reed, Shelby D.; Sanchez, Juan; Leon, Andrew C.
2013-01-01
Objective: This article captures the proceedings of a meeting aimed at defining clinically meaningful effects for use in randomized controlled trials for psychopharmacological agents. Design: Experts from a variety of disciplines defined clinically meaningful effects from their perspectives along with viewpoints about how to design and interpret randomized controlled trials. Setting: The article offers relevant, practical, and sometimes anecdotal information about clinically meaningful effects and how to interpret them. Participants: The concept for this session was the work of co-chairs Richard Keefe and the late Andy Leon. Faculty included Richard Keefe, PhD; James McNulty, AbScB; Robert S. Epstein, MD, MS; Shelby D. Reed, PhD; Juan Sanchez, MD; Ginger Haynes, PhD; Andrew C. Leon, PhD; Helena Chmura Kraemer, PhD; Ellen Frank, PhD, and Kenneth L. Davis, MD. Results: The term clinically meaningful effect is an important aspect of designing and interpreting randomized controlled trials but can be particularly difficult in the setting of psychopharmacology where effect size may be modest, particularly over the short term, because of a strong response to placebo. Payers, regulators, patients, and clinicians have different concerns about clinically meaningful effects and may describe these terms differently. The use of moderators in success rate differences may help better delineate clinically meaningful effects. Conclusion: There is no clear consensus on a single definition for clinically meaningful differences in randomized controlled trials, and investigators must be sensitive to specific concerns of stakeholders in psychopharmacology in order to design and execute appropriate clinical trials. PMID:23882433
Sparks, Jeffrey A.; Iversen, Maura D.; Kroouze, Rachel Miller; Mahmoud, Taysir G.; Triedman, Nellie A.; Kalia, Sarah S.; Atkinson, Michael L.; Lu, Bing; Deane, Kevin D.; Costenbader, Karen H.; Green, Robert C.; Karlson, Elizabeth W.
2014-01-01
We present the rationale, design features, and protocol of the Personalized Risk Estimator for Rheumatoid Arthritis (PRE-RA) Family Study (ClinicalTrials.gov NCT02046005). The PRE-RA Family Study is an NIH-funded prospective, randomized controlled trial designed to compare the willingness to change behaviors in first-degree relatives of rheumatoid arthritis (RA) patients without RA after exposure to RA risk educational programs. Consented subjects are randomized to receive education concerning their personalized RA risk based on demographics, RA-associated behaviors, genetics and biomarkers or to receive standard RA information. Four behavioral factors associated with RA risk were identified from prior studies for inclusion in the risk estimate: cigarette smoking, excess body weight, poor oral health, and low fish intake. Personalized RA risk information is presented through an online tool that collects data on an individual's specific age, gender, family history, and risk-related behaviors; presents genetic and biomarker results; displays relative and absolute risk of RA; and provides personalized feedback and education. The trial outcomes will be changes in willingness to alter behaviors from baseline to 6 weeks, 6 months, and 12 months in the three intervention groups. The design and execution of this trial that targets a special population at risk for RA, while incorporating varied risk factors into a single risk tool, offer distinct challenges. We provide the theoretical rationale for the PRE-RA Family Study and highlight particular design features of this trial that utilize personalized risk education as an intervention. PMID:25151341
Evaluation of nursing practice: process and critique.
Braunstein, M S
1998-01-01
This article describes the difficulties in conducting clinical trials to evaluate nursing practice models. Suggestions are offered for strengthening the process. A clinical trial of a nursing practice model based on a synthesis of Aristotelian theory with Rogers' science is described. The rationale for decisions regarding the research procedures used in presented. Methodological limitations of the study design and the specifications of the practice model are examined. It is concluded that clear specification of theoretical relationships within a practice model and clear identification of key intervening variables will enable researchers to better connect the treatment with the outcome.
2014-01-01
Background Cerebral palsy (CP) and brain injury (BI) are common conditions that have devastating effects on a child’s ability to use their hands. Hand splinting and task-specific training are two interventions that are often used to address deficits in upper limb skills, both in isolation or concurrently. The aim of this paper is to describe the method to be used to conduct two randomised controlled trials (RCT) investigating (a) the immediate effect of functional hand splints, and (b) the effect of functional hand splints used concurrently with task-specific training compared to functional hand splints alone, and to task-specific training alone in children with CP and BI. The Cognitive Orientation to Occupational Performance (CO-OP) approach will be the task-specific training approach used. Methods/Design Two concurrent trials; a two group, parallel design, RCT with a sample size of 30 participants (15 per group); and a three group, parallel design, assessor blinded, RCT with a sample size of 45 participants (15 per group). Inclusion criteria: age 4-15 years; diagnosis of CP or BI; Manual Abilities Classification System (MACS) level I – IV; hand function goals; impaired hand function; the cognitive, language and behavioural ability to participate in CO-OP. Participants will be randomly allocated to one of 3 groups; (1) functional hand splint only (n=15); (2) functional hand splint combined with task-specific training (n=15); (3) task-specific training only (n=15). Allocation concealment will be achieved using sequentially numbered, sealed opaque envelopes opened by an off-site officer after baseline measures. Treatment will be provided for a period of 2 weeks, with outcome measures taken at baseline, 1 hour after randomisation, 2 weeks and 10 weeks. The functional hand splint will be a wrist cock-up splint (+/- thumb support or supination strap). Task-specific training will involve 10 sessions of CO-OP provided in a group of 2-4 children. Primary outcome measures will be the Canadian Occupational Performance Measure (COPM) and the Goal Attainment Scale (GAS). Analysis will be conducted on an intention-to-treat basis. Discussion This paper outlines the protocol for two randomised controlled trials investigating functional hand splints and CO-OP for children with CP and BI. PMID:25023385
Keefe, Richard S E; Kraemer, Helena C; Epstein, Robert S; Frank, Ellen; Haynes, Ginger; Laughren, Thomas P; McNulty, James; Reed, Shelby D; Sanchez, Juan; Leon, Andrew C
2013-05-01
This article captures the proceedings of a meeting aimed at defining clinically meaningful effects for use in randomized controlled trials for psychopharmacological agents. Experts from a variety of disciplines defined clinically meaningful effects from their perspectives along with viewpoints about how to design and interpret randomized controlled trials. The article offers relevant, practical, and sometimes anecdotal information about clinically meaningful effects and how to interpret them. The concept for this session was the work of co-chairs Richard Keefe and the late Andy Leon. Faculty included Richard Keefe, PhD; James McNulty, AbScB; Robert S. Epstein, MD, MS; Shelby D. Reed, PhD; Juan Sanchez, MD; Ginger Haynes, PhD; Andrew C. Leon, PhD; Helena Chmura Kraemer, PhD; Ellen Frank, PhD, and Kenneth L. Davis, MD. The term clinically meaningful effect is an important aspect of designing and interpreting randomized controlled trials but can be particularly difficult in the setting of psychopharmacology where effect size may be modest, particularly over the short term, because of a strong response to placebo. Payers, regulators, patients, and clinicians have different concerns about clinically meaningful effects and may describe these terms differently. The use of moderators in success rate differences may help better delineate clinically meaningful effects. There is no clear consensus on a single definition for clinically meaningful differences in randomized controlled trials, and investigators must be sensitive to specific concerns of stakeholders in psychopharmacology in order to design and execute appropriate clinical trials.
Huber, Lara
2011-06-01
In the neurosciences digital databases more and more are becoming important tools of data rendering and distributing. This development is due to the growing impact of imaging based trial design in cognitive neuroscience, including morphological as much as functional imaging technologies. As the case of the 'Laboratory of Neuro Imaging' (LONI) is showing, databases are attributed a specific epistemological power: Since the 1990s databasing is seen to foster the integration of neuroscientific data, although local regimes of data production, -manipulation and--interpretation are also challenging this development. Databasing in the neurosciences goes along with the introduction of new structures of integrating local data, hence establishing digital spaces of knowledge (epistemic spaces): At this stage, inherent norms of digital databases are affecting regimes of imaging-based trial design, for example clinical research into Alzheimer's disease.
Preventing youth access to alcohol: outcomes from a multi-community time-series trial*.
Wagenaar, Alexander C; Toomey, Traci L; Erickson, Darin J
2005-03-01
AIMS/INTERVENTION: The Complying with the Minimum Drinking Age project (CMDA) is a community trial designed to test effects of two interventions designed to reduce alcohol sales to minors: (1) training for management of retail alcohol establishments and (2) enforcement checks of alcohol establishments. CMDA is a multi-community time-series quasi-experimental trial with a nested cohort design. CMDA was implemented in 20 cities in four geographic areas in the US Midwest. The core outcome, propensity for alcohol sales to minors, was directly tested with research staff who attempted to purchase alcohol without showing age identification using a standardized protocol in 602 on-premise and 340 off-premise alcohol establishments. Data were collected every other week in all communities over 4 years. Mixed-model regression and Box-Jenkins time-series analyses were used to assess short- and long-term establishment-specific and general community-level effects of the two interventions. Effects of the training intervention were mixed. Specific deterrent effects were observed for enforcement checks, with an immediate 17% reduction in likelihood of sales to minors. These effects decayed entirely within 3 months in off-premise establishments and to an 8.2% reduction in on-premise establishments. Enforcement checks prevent alcohol sales to minors. At the intensity levels tested, enforcement primarily affected specific establishments checked, with limited diffusion to the whole community. Finally, most of the enforcement effect decayed within 3 months, suggesting that a regular schedule of enforcement is necessary to maintain deterrence.
Dose escalation methods in phase I cancer clinical trials.
Le Tourneau, Christophe; Lee, J Jack; Siu, Lillian L
2009-05-20
Phase I clinical trials are an essential step in the development of anticancer drugs. The main goal of these studies is to establish the recommended dose and/or schedule of new drugs or drug combinations for phase II trials. The guiding principle for dose escalation in phase I trials is to avoid exposing too many patients to subtherapeutic doses while preserving safety and maintaining rapid accrual. Here we review dose escalation methods for phase I trials, including the rule-based and model-based dose escalation methods that have been developed to evaluate new anticancer agents. Toxicity has traditionally been the primary endpoint for phase I trials involving cytotoxic agents. However, with the emergence of molecularly targeted anticancer agents, potential alternative endpoints to delineate optimal biological activity, such as plasma drug concentration and target inhibition in tumor or surrogate tissues, have been proposed along with new trial designs. We also describe specific methods for drug combinations as well as methods that use a time-to-event endpoint or both toxicity and efficacy as endpoints. Finally, we present the advantages and drawbacks of the various dose escalation methods and discuss specific applications of the methods in developmental oncotherapeutics.
Hernán, Miguel A.; Sauer, Brian C.; Hernández-Díaz, Sonia; Platt, Robert; Shrier, Ian
2016-01-01
Many analyses of observational data are attempts to emulate a target trial. The emulation of the target trial may fail when researchers deviate from simple principles that guide the design and analysis of randomized experiments. We review a framework to describe and prevent biases, including immortal time bias, that result from a failure to align start of follow-up, specification of eligibility, and treatment assignment. We review some analytic approaches to avoid these problems in comparative effectiveness or safety research. PMID:27237061
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bekelman, Justin E., E-mail: bekelman@uphs.upenn.edu; Deye, James A.; Vikram, Bhadrasain
2012-07-01
Purpose: In the context of national calls for reorganizing cancer clinical trials, the National Cancer Institute sponsored a 2-day workshop to examine challenges and opportunities for optimizing radiotherapy quality assurance (QA) in clinical trial design. Methods and Materials: Participants reviewed the current processes of clinical trial QA and noted the QA challenges presented by advanced technologies. The lessons learned from the radiotherapy QA programs of recent trials were discussed in detail. Four potential opportunities for optimizing radiotherapy QA were explored, including the use of normal tissue toxicity and tumor control metrics, biomarkers of radiation toxicity, new radiotherapy modalities such asmore » proton beam therapy, and the international harmonization of clinical trial QA. Results: Four recommendations were made: (1) to develop a tiered (and more efficient) system for radiotherapy QA and tailor the intensity of QA to the clinical trial objectives (tiers include general credentialing, trial-specific credentialing, and individual case review); (2) to establish a case QA repository; (3) to develop an evidence base for clinical trial QA and introduce innovative prospective trial designs to evaluate radiotherapy QA in clinical trials; and (4) to explore the feasibility of consolidating clinical trial QA in the United States. Conclusion: Radiotherapy QA can affect clinical trial accrual, cost, outcomes, and generalizability. To achieve maximum benefit, QA programs must become more efficient and evidence-based.« less
Bekelman, Justin E; Deye, James A; Vikram, Bhadrasain; Bentzen, Soren M; Bruner, Deborah; Curran, Walter J; Dignam, James; Efstathiou, Jason A; FitzGerald, T J; Hurkmans, Coen; Ibbott, Geoffrey S; Lee, J Jack; Merchant, Thomas E; Michalski, Jeff; Palta, Jatinder R; Simon, Richard; Ten Haken, Randal K; Timmerman, Robert; Tunis, Sean; Coleman, C Norman; Purdy, James
2012-07-01
In the context of national calls for reorganizing cancer clinical trials, the National Cancer Institute sponsored a 2-day workshop to examine challenges and opportunities for optimizing radiotherapy quality assurance (QA) in clinical trial design. Participants reviewed the current processes of clinical trial QA and noted the QA challenges presented by advanced technologies. The lessons learned from the radiotherapy QA programs of recent trials were discussed in detail. Four potential opportunities for optimizing radiotherapy QA were explored, including the use of normal tissue toxicity and tumor control metrics, biomarkers of radiation toxicity, new radiotherapy modalities such as proton beam therapy, and the international harmonization of clinical trial QA. Four recommendations were made: (1) to develop a tiered (and more efficient) system for radiotherapy QA and tailor the intensity of QA to the clinical trial objectives (tiers include general credentialing, trial-specific credentialing, and individual case review); (2) to establish a case QA repository; (3) to develop an evidence base for clinical trial QA and introduce innovative prospective trial designs to evaluate radiotherapy QA in clinical trials; and (4) to explore the feasibility of consolidating clinical trial QA in the United States. Radiotherapy QA can affect clinical trial accrual, cost, outcomes, and generalizability. To achieve maximum benefit, QA programs must become more efficient and evidence-based. Copyright © 2012 Elsevier Inc. All rights reserved.
ERIC Educational Resources Information Center
Hedberg, E. C.; Hedges, Larry V.
2014-01-01
Randomized experiments are often considered the strongest designs to study the impact of educational interventions. Perhaps the most prevalent class of designs used in large scale education experiments is the cluster randomized design in which entire schools are assigned to treatments. In cluster randomized trials (CRTs) that assign schools to…
Guidelines for the Design and Conduct of Clinical Studies in Knee Articular Cartilage Repair
Mithoefer, Kai; Saris, Daniel B.F.; Farr, Jack; Kon, Elizaveta; Zaslav, Kenneth; Cole, Brian J.; Ranstam, Jonas; Yao, Jian; Shive, Matthew; Levine, David; Dalemans, Wilfried; Brittberg, Mats
2011-01-01
Objective: To summarize current clinical research practice and develop methodological standards for objective scientific evaluation of knee cartilage repair procedures and products. Design: A comprehensive literature review was performed of high-level original studies providing information relevant for the design of clinical studies on articular cartilage repair in the knee. Analysis of cartilage repair publications and synopses of ongoing trials were used to identify important criteria for the design, reporting, and interpretation of studies in this field. Results: Current literature reflects the methodological limitations of the scientific evidence available for articular cartilage repair. However, clinical trial databases of ongoing trials document a trend suggesting improved study designs and clinical evaluation methodology. Based on the current scientific information and standards of clinical care, detailed methodological recommendations were developed for the statistical study design, patient recruitment, control group considerations, study endpoint definition, documentation of results, use of validated patient-reported outcome instruments, and inclusion and exclusion criteria for the design and conduct of scientifically sound cartilage repair study protocols. A consensus statement among the International Cartilage Repair Society (ICRS) and contributing authors experienced in clinical trial design and implementation was achieved. Conclusions: High-quality clinical research methodology is critical for the optimal evaluation of current and new cartilage repair technologies. In addition to generally applicable principles for orthopedic study design, specific criteria and considerations apply to cartilage repair studies. Systematic application of these criteria and considerations can facilitate study designs that are scientifically rigorous, ethical, practical, and appropriate for the question(s) being addressed in any given cartilage repair research project. PMID:26069574
Liu, M; Wei, L; Zhang, J
2006-01-01
Missing data in clinical trials are inevitable. We highlight the ICH guidelines and CPMP points to consider on missing data. Specifically, we outline how we should consider missing data issues when designing, planning and conducting studies to minimize missing data impact. We also go beyond the coverage of the above two documents, provide a more detailed review of the basic concepts of missing data and frequently used terminologies, and examples of the typical missing data mechanism, and discuss technical details and literature for several frequently used statistical methods and associated software. Finally, we provide a case study where the principles outlined in this paper are applied to one clinical program at protocol design, data analysis plan and other stages of a clinical trial.
Conducting feasibilities in clinical trials: an investment to ensure a good study.
Rajadhyaksha, Viraj
2010-07-01
Conducting clinical trial feasibility is one of the first steps in clinical trial conduct. This process includes assessing internal and environmental capacity, alignment of the clinical trial in terms of study design, dose of investigational product, comparator, patient type, with the local environment and assessing potential of conducting clinical trial in a specific country. A robust feasibility also ensures a realistic assessment and capability to conduct the clinical trial. For local affiliates of pharmaceutical organizations, and contract research organizations, this is a precursor to study placement and influences the decision of study placement. This article provides details on different types of feasibilities, information which is to be included and relevance of each. The article also aims to provide practical hands-on suggestions to make feasibilities more realistic and informative.
Phadnis, Milind A; Wetmore, James B; Mayo, Matthew S
2017-11-20
Traditional methods of sample size and power calculations in clinical trials with a time-to-event end point are based on the logrank test (and its variations), Cox proportional hazards (PH) assumption, or comparison of means of 2 exponential distributions. Of these, sample size calculation based on PH assumption is likely the most common and allows adjusting for the effect of one or more covariates. However, when designing a trial, there are situations when the assumption of PH may not be appropriate. Additionally, when it is known that there is a rapid decline in the survival curve for a control group, such as from previously conducted observational studies, a design based on the PH assumption may confer only a minor statistical improvement for the treatment group that is neither clinically nor practically meaningful. For such scenarios, a clinical trial design that focuses on improvement in patient longevity is proposed, based on the concept of proportional time using the generalized gamma ratio distribution. Simulations are conducted to evaluate the performance of the proportional time method and to identify the situations in which such a design will be beneficial as compared to the standard design using a PH assumption, piecewise exponential hazards assumption, and specific cases of a cure rate model. A practical example in which hemorrhagic stroke patients are randomized to 1 of 2 arms in a putative clinical trial demonstrates the usefulness of this approach by drastically reducing the number of patients needed for study enrollment. Copyright © 2017 John Wiley & Sons, Ltd.
ERIC Educational Resources Information Center
Larkin, Ashleigh; Dwyer, Angela
2016-01-01
This paper discusses the results of an intensive mentoring program trial designed to address retention issues with first year students in Justice degrees. The purpose of the program was to reduce student attrition, specifically for non-school leaver Justice students, by creating a culture of student cooperation and support. In line with previous…
Balasubramaniam, Gowrie; Parker, Trisha; Turner, David; Parker, Mike; Scales, Jonathan; Harnett, Patrick; Harrison, Michael; Ahmed, Khalid; Bhagat, Sweta; Marianayagam, Thiraupathy; Pitzalis, Costantino; Mallen, Christian; Roddy, Edward; Almond, Mike; Dasgupta, Bhaskar
2017-09-05
Acute gout occurs in people with chronic kidney disease, who are commonly older people with comorbidities such as hypertension, heart disease and diabetes. Potentially harmful treatments are administered to these vulnerable patients due to a lack of clear evidence. Newly available treatment that targets a key inflammatory pathway in acute gout attacks provides an opportunity to undertake the first-ever trial specifically looking treating people with kidney disease. This paper describes the protocol for a feasibility randomised controlled trial (RCT) comparing anakinra, a novel interleukin-1 antagonist versus steroids in people with chronic kidney disease (ASGARD). ASGARD is a two-parallel group double-blind, double-dummy multicentre RCT comparing anakinra 100 mg, an interleukin-1 antagonist, subcutaneous for 5 days against intramuscular methylprednisolone 120 mg. The primary objective is to assess the feasibility of the trial design and procedures for a definitive RCT. The specific aims are: (1) test recruitment and retention rates and willingness to be randomised; (2) test eligibility criteria; (3) collect and analyse outcome data to inform sample and power calculations for a trial of efficacy; (4) collect economic data to inform a future economic evaluation estimating costs of treatment and (5) assess capacity of the project to scale up to a national multicentre trial. We will also gather qualitative insights from participants. It aims to recruit 32 patients with a 1:1 randomisation. Information from this feasibility study will help design a definitive trial and provide general information in designing acute gout studies. The London-Central Ethics Committee approved the protocol. The results will be disseminated in peer-reviewed journals and at scientific conferences. EudraCT No. 2015-001787-19, NCT/Clinicalstrials.gov No. NCT02578394, pre-results, WHO Universal Trials Reference No. U1111-1175-1977. NIHR Grant PB-PG-0614-34090. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.
Gender indexing in publications of clinical trials: 1991-2008.
Drye, Lea T; Meinert, Jill L; Meinert, Curtis L
2010-12-01
In 1993 Congress passed the NIH Revitalization Act, which instructed the Director of the NIH to ensure that phase III clinical trials are 'designed and carried out in a manner sufficient to provide for a valid analysis of whether the variables being studied in the trial affect females or members of minority groups, as the case may be, differently than other subjects in the trial.' The purpose of this article is to track the PubMed indexing of gender in clinical trial publications since 1991 with a view toward assessing the impact of the legislation on the number of gender specific trials. We searched PubMed for full-length publications from years 1991 to 2008 of research on humans indexed as publication type 'clinical trial', 'randomized clinical trial' and multicenter randomized trial ('multicenter study' AND 'randomized clinical trial'), and counted the number of trials indexed as male-only, female-only, male and female, and gender unknown in PubMed. The majority of trial publications were indexed in PubMed as including both genders. The proportion of publications indexed as including both genders has increased while the number of publications not indexed with respect to gender and the number of publications indexed as male-only have decreased. In 2005, approximately 13% of NIH expenditures were for female specific or related research compared to 6% for male specific or related research. The proportion of clinical trial publications that were indexed in PubMed as including females began to increase before the legislation so it is difficult to conclude that changes in the number of female-only or male-only trials are due to the legislation. PubMed listings do not include gender enrollment, so female and male enrollment totals could not be compared. The NIH policy should be rewritten to be made gender neutral to bring it in line with the principle of justice as embodied in the Belmont Report.
Stem Cell Trials for Cardiovascular Medicine: Ethical Rationale
Teraa, Martin; Hesam, Husna; van Delden, Johannes J.M.; Verhaar, Marianne C.; Bredenoord, Annelien L.
2014-01-01
Stem cell-based interventions provide new treatment prospects for many disease conditions, including cardiovascular disorders. Clinical trials are necessary to collect adequate evidence on (long-term) safety and efficacy of novel interventions such as stem cells, but the design and launch of clinical trials, from first-in-human studies to larger randomized controlled trials (RCTs), is scientifically and ethically challenging. Stem cells are different from traditional pharmaceuticals, surgical procedures, and medical devices in the following ways: the novelty and complexity of stem cells, the invasiveness of the procedures, and the novel aim of regeneration. These specifics, combined with the characteristics of the study population, will have an impact on the design and ethics of RCTs. The recently closed JUVENTAS trial will serve as an example to identify the (interwoven) scientific and ethical challenges in the design and launch of stem cell RCTs. The JUVENTAS trial has investigated the efficacy of autologous bone marrow cells in end-stage vascular patients, in a double-blind sham-controlled design. We first describe the choices, considerations, and experiences of the JUVENTAS team. Subsequently, we identify the main ethical and scientific challenges and discuss what is important to consider in the design of future stem cell RCTs: assessment of risks and benefits, the choice for outcome measures, the choice for the comparator, the appropriate selection of participants, and adequate informed consent. Additionally, the stem cell field is highly in the spotlight due to the (commercial) interests and expectations. This warrants a cautious pace of translation and scrupulous set up of clinical trials, as failures could put the field in a negative light. At the same time, knowledge from clinical trials is necessary for the field to progress. We conclude that in the scientifically and ethically challenging field of stem cell RCTs, researchers and clinicians have to maneuver between the Skylla of hyper accelerated translation without rigorously conducted RCTs and the Charybdis of the missed opportunity of valuable knowledge. PMID:24164351
Reward-prospect interacts with trial-by-trial preparation for potential distraction
Marini, Francesco; van den Berg, Berry; Woldorff, Marty G.
2015-01-01
When attending for impending visual stimuli, cognitive systems prepare to identify relevant information while ignoring irrelevant, potentially distracting input. Recent work (Marini et al., 2013) showed that a supramodal distracter-filtering mechanism is invoked in blocked designs involving expectation of possible distracter stimuli, although this entails a cost (distraction-filtering cost) on speeded performance when distracters are expected but not presented. Here we used an arrow-flanker task to study whether an analogous cost, potentially reflecting the recruitment of a specific distraction-filtering mechanism, occurs dynamically when potential distraction is cued trial-to-trial (cued distracter-expectation cost). In order to promote the maximal utilization of cue information by participants, in some experimental conditions the cue also signaled the possibility of earning a monetary reward for fast and accurate performance. This design also allowed us to investigate the interplay between anticipation for distracters and anticipation of reward, which is known to engender attentional preparation. Only in reward contexts did participants show a cued distracter-expectation cost, which was larger with higher reward prospect and when anticipation for both distracters and reward were manipulated trial-to-trial. Thus, these results indicate that reward prospect interacts with the distracter expectation during trial-by-trial preparatory processes for potential distraction. These findings highlight how reward guides cue-driven attentional preparation. PMID:26180506
Reward-prospect interacts with trial-by-trial preparation for potential distraction.
Marini, Francesco; van den Berg, Berry; Woldorff, Marty G
2015-02-01
When attending for impending visual stimuli, cognitive systems prepare to identify relevant information while ignoring irrelevant, potentially distracting input. Recent work (Marini et al., 2013) showed that a supramodal distracter-filtering mechanism is invoked in blocked designs involving expectation of possible distracter stimuli, although this entails a cost ( distraction-filtering cost ) on speeded performance when distracters are expected but not presented. Here we used an arrow-flanker task to study whether an analogous cost, potentially reflecting the recruitment of a specific distraction-filtering mechanism, occurs dynamically when potential distraction is cued trial-to-trial ( cued distracter-expectation cost ). In order to promote the maximal utilization of cue information by participants, in some experimental conditions the cue also signaled the possibility of earning a monetary reward for fast and accurate performance. This design also allowed us to investigate the interplay between anticipation for distracters and anticipation of reward, which is known to engender attentional preparation. Only in reward contexts did participants show a cued distracter-expectation cost, which was larger with higher reward prospect and when anticipation for both distracters and reward were manipulated trial-to-trial. Thus, these results indicate that reward prospect interacts with the distracter expectation during trial-by-trial preparatory processes for potential distraction. These findings highlight how reward guides cue-driven attentional preparation.
The effect of St John’s wort extracts on CYP3A: a systematic review of prospective clinical trials
Whitten, D L; Myers, S P; Hawrelak, J A; Wohlmuth, H
2006-01-01
Aim The aim of this systematic review was to assess the quality and outcomes of clinical trials investigating the effect of St John’s wort extracts on the metabolism of drugs by CYP3A. Methods Prospective clinical trials assessing the effect of St John’s wort (SJW) extracts on metabolism by CYP3A were identified through computer-based searches (from their inception to May 2005) of Medline, Cinahl, PsycINFO, AMED, Current Contents and Embase, hand-searches of bibliographies of relevant papers and consultation with manufacturers and researchers in the field. Two reviewers selected trials for inclusion, independently extracted data and recorded details on study design. Results Thirty-one studies met the eligibility criteria. More than two-thirds of the studies employed a before-and-after design, less than one-third of the studies used a crossover design, and only three studies were double-blind and placebo controlled. In 12 studies the SJW extract had been assayed, and 14 studies stated the specific SJW extract used. Results from 26 studies, including all of the 19 studies that used high-dose hyperforin extracts (>10 mg day−1), had outcomes consistent with CYP3A induction. The three studies using low-dose hyperforin extracts (<4 mg day−1) demonstrated no significant effect on CYP3A. Conclusion There is reasonable evidence to suggest that high-dose hyperforin SJW extracts induce CYP3A. More studies are required to determine whether decreased CYP3A induction occurs after low-dose hyperforin extracts. Future studies should adopt study designs with a control phase or control group, identify the specific SJW extract employed and provide quantitative analyses of key constituents. PMID:17010103
Gaglio, Bridget; Phillips, Siobhan M; Heurtin-Roberts, Suzanne; Sanchez, Michael A; Glasgow, Russell E
2014-08-28
The need for high-quality evidence that is applicable in real-world, routine settings continues to increase. Pragmatic trials are designed to evaluate the effectiveness of interventions in real-world settings, whereas explanatory trials aim to test whether an intervention works under optimal situations. There is a continuum between explanatory and pragmatic trials. Most trials have aspects of both, making it challenging to label and categorize a trial and to evaluate its potential for translation into practice. We summarize our experience applying the Pragmatic-Explanatory Continuum Indicator Summary (PRECIS) combined with external validity items based on the Reach, Effectiveness, Adoption, Implementation, and Maintenance (RE-AIM) framework to three studies to provide a more robust and comprehensive assessment of trial characteristics related to translation of research. We summarize lessons learned using domains from the combined frameworks for use in study planning, evaluating specific studies, and reviewing the literature and make recommendations for future use. A variety of coders can be trained to use the PRECIS and RE-AIM domains. These domains can also be used for diverse purposes, content areas, and study types, but are not without challenges. Both PRECIS and RE-AIM domains required modification in two of the three studies to evaluate and rate domains specific to study type. Lessons learned involved: dedicating enough time for training activities related to the domains; use of reviewers with a range of familiarity with specific study protocols; how to best adapt ratings that reflect complex study designs; and differences of opinion regarding the value of creating a composite score for these criteria. Combining both frameworks can specifically help identify where and how a study is and is not pragmatic. Using both PRECIS and RE-AIM allows for standard reporting of key study characteristics related to pragmatism and translation. Such measures should be used more consistently to help plan more pragmatic studies, evaluate progress, increase transparency of reporting, and integrate literature to facilitate translation of research into practice and policy.
The N-of-1 Clinical Trial: A Timely Research Opportunity in Homeopathy.
Ulbrich-Zürni, Susanne; Teut, Michael; Roll, Stephanie; Mathie, Robert T
2018-02-01
The randomised controlled trial (RCT) is considered the 'gold standard' for establishing treatment efficacy or effectiveness of an intervention, but its data do not infer response in an individual patient. Individualised clinical care, a fundamental principle in complementary and alternative medicine (CAM), including homeopathy, seems well disposed in principle to being researched by single-patient (N-of-1) study design. Guidelines for reporting N-of-1 trials have recently been developed. To overview the current status in the literature of the N-of-1 method and its application in medicine, including CAM. To consider whether the N-of-1 trial design offers an opportunity for novel research in homeopathy. N-OF-1 TRIAL DESIGN: The N-of-1 trial applies the principles of the conventional crossover, blinded, RCT design. The treatment under study and the comparator are repeated in a randomised order, and with suitable washout time, over a defined period. N-of-1 design is constrained for use in chronic stable conditions, and for interventions that have quick onset and cessation of effect, with modest or negligible carryover. Outcome data can be aggregated and interpreted for the individual subject; they can also be pooled with data from several similar N-of-1 trials, enabling more generalisable conclusions. THE N-OF-1 TRIAL IN CAM: The typical individualisation of patient care can be accommodated in N-of-1 study design if the patient and the specific therapeutic intervention are selected within the constraints of the method. Application of the N-of-1 method in CAM has been advocated but has been mainly limited, in practice, to a small number of studies in herbal and traditional Chinese medicine. THE N-OF-1 TRIAL IN HOMEOPATHY: Individualised homeopathy can be accommodated for investigation within the same methodological constraints; less in-depth homeopathic approaches to prescribing are also amendable to investigation using the N-of-1 method. No such studies have been published. We identify three main targets in its ready applicability to homeopathy: (1) to optimise clinical care in an individual patient; (2) to investigate whether the outcomes of treatment using homeopathy differ from those of placebo; (3) to aggregate data from a series of N-of-1 trials to enable broader conclusions about a group of patients or intervention. The N-of-1 trial design offers important new investigative possibilities in homeopathy and should be explored as a means to optimise individualised health care or investigate effectiveness of the homeopathic intervention compared with placebo in individual subjects. The Faculty of Homeopathy.
Design and implementation of a fault-tolerant and dynamic metadata database for clinical trials
NASA Astrophysics Data System (ADS)
Lee, J.; Zhou, Z.; Talini, E.; Documet, J.; Liu, B.
2007-03-01
In recent imaging-based clinical trials, quantitative image analysis (QIA) and computer-aided diagnosis (CAD) methods are increasing in productivity due to higher resolution imaging capabilities. A radiology core doing clinical trials have been analyzing more treatment methods and there is a growing quantity of metadata that need to be stored and managed. These radiology centers are also collaborating with many off-site imaging field sites and need a way to communicate metadata between one another in a secure infrastructure. Our solution is to implement a data storage grid with a fault-tolerant and dynamic metadata database design to unify metadata from different clinical trial experiments and field sites. Although metadata from images follow the DICOM standard, clinical trials also produce metadata specific to regions-of-interest and quantitative image analysis. We have implemented a data access and integration (DAI) server layer where multiple field sites can access multiple metadata databases in the data grid through a single web-based grid service. The centralization of metadata database management simplifies the task of adding new databases into the grid and also decreases the risk of configuration errors seen in peer-to-peer grids. In this paper, we address the design and implementation of a data grid metadata storage that has fault-tolerance and dynamic integration for imaging-based clinical trials.
Sparks, Jeffrey A; Iversen, Maura D; Miller Kroouze, Rachel; Mahmoud, Taysir G; Triedman, Nellie A; Kalia, Sarah S; Atkinson, Michael L; Lu, Bing; Deane, Kevin D; Costenbader, Karen H; Green, Robert C; Karlson, Elizabeth W
2014-09-01
We present the rationale, design features, and protocol of the Personalized Risk Estimator for Rheumatoid Arthritis (PRE-RA) Family Study (ClinicalTrials.gov NCT02046005). The PRE-RA Family Study is an NIH-funded prospective, randomized controlled trial designed to compare the willingness to change behaviors in first-degree relatives of rheumatoid arthritis (RA) patients without RA after exposure to RA risk educational programs. Consented subjects are randomized to receive education concerning their personalized RA risk based on demographics, RA-associated behaviors, genetics, and biomarkers or to receive standard RA information. Four behavioral factors associated with RA risk were identified from prior studies for inclusion in the risk estimate: cigarette smoking, excess body weight, poor oral health, and low fish intake. Personalized RA risk information is presented through an online tool that collects data on an individual's specific age, gender, family history, and risk-related behaviors; presents genetic and biomarker results; displays relative and absolute risk of RA; and provides personalized feedback and education. The trial outcomes will be changes in willingness to alter behaviors from baseline to 6 weeks, 6 months, and 12 months in the three intervention groups. The design and the execution of this trial that targets a special population at risk for RA, while incorporating varied risk factors into a single risk tool, offer distinct challenges. We provide the theoretical rationale for the PRE-RA Family Study and highlight particular design features of this trial that utilize personalized risk education as an intervention. Copyright © 2014 Elsevier Inc. All rights reserved.
ERIC Educational Resources Information Center
Schmied, Emily; Parada, Humberto; Horton, Lucy; Ibarra, Leticia; Ayala, Guadalupe
2015-01-01
"Entre Familia: Reflejos de Salud" was a successful family-based randomized controlled trial designed to improve dietary behaviors and intake among U.S. Latino families, specifically fruit and vegetable intake. The novel intervention design merged a community health worker ("promotora") model with an entertainment-education…
ERIC Educational Resources Information Center
Rizvi, Shireen L.; Nock, Matthew K.
2008-01-01
Single-case experimental designs (SCEDs) provide a time- and cost-effective alternative to randomized clinical trials and offer significant advantages in terms of internal and external validity. A brief history and primer on SCEDs is provided, specifically for use in suicide intervention research. Various SCED methodologies, such as AB, ABAB,…
A survey of facilitators and barriers to recruitment to the MAGNETIC trial.
Kaur, Geetinder; Smyth, Rosalind L; Powell, Colin V E; Williamson, Paula
2016-12-23
Recruitment to randomised controlled trials with children is challenging. It is imperative to understand the factors that boost or hinder recruitment of children to clinical trials. We conducted a survey of facilitators and barriers to recruitment to the MAGNETIC trial, using a previously developed web-based tool. MAGNETIC is a multicentre randomised trial of nebulised magnesium in acute severe asthma, recruiting 508 children from 30 UK sites. Recruiters were asked to grade a list of factors from -3 to +3 depending on whether the factor was perceived as a strong, intermediate or weak barrier (-3 to -1) or facilitator (+1 to + 3), and using (0) if it was thought to be not applicable. Free text responses were invited on strategies applied to counter the identified barriers. The commonly identified facilitators were motivation and experience of study teams, effective communication and coordination between teams at site and between sites and the Clinical Trials Unit, the presence of designated research nurses, good trial management, clinical trial publicity, simple inclusion criteria, effective communication with parents and presentation of trial information in a simple and clear manner. The commonly identified barriers were heavy clinical workload, shift patterns of work, Good Clinical Practice (GCP) training, inadequate number of trained staff, time and setting of consent seeking, non-availability of research staff out of hours and parents' concerns about their child taking an experimental medicine. Having a designated research nurse, arranging GCP training and trial-related training sessions for staff were the most commonly reported interventions. This study highlights important generic and trial-specific facilitators and barriers to recruitment to a paediatric trial in the acute setting and provides information on the recruitment strategies or interventions that were applied to overcome these barriers. This information can be very useful in informing the design and conduct of future clinical trials with children, particularly in the acute or emergency setting. ISRCTN, ISRCTN81456894 . Registered on 15 November 2007.
Crothers, Amy; Walker, Bruce; French, Simon D
2008-01-01
Background The one year prevalence of thoracic back pain has been estimated as 17% compared to 64% for neck pain and 67% for low back pain. At present only one randomised controlled trial has been performed assessing the efficacy of spinal manipulative therapy (SMT) for thoracic spine pain. In addition no high quality trials have been performed to test the efficacy and effectiveness of Graston Technique® (GT), a soft tissue massage therapy using hand-held stainless steel instruments. The objective of this trial is to determine the efficacy of SMT and GT compared to a placebo for the treatment of non specific thoracic spine pain. Methods Eighty four eligible people with non specific thoracic pain mid back pain of six weeks or more will be randomised to one of three groups, either SMT, GT, or a placebo (de-tuned ultrasound). Each group will receive up to 10 supervised treatment sessions at the Murdoch University Chiropractic student clinic over a 4-week period. Treatment outcomes will be measured at baseline, one week after their first treatment, upon completion of the 4-week intervention period and at three, six and twelve months post randomisation. Outcome measures will include the Oswestry Back Pain Disability Index and the Visual Analogue Scale (VAS). Intention to treat analysis will be utilised in the statistical analysis of any group treatment effects. Trial Registration This trial was registered with the Australia and New Zealand Clinical Trials Registry on the 7th February 2008. Trial number: ACTRN12608000070336 PMID:18959807
McAlindon, T E; Driban, J B; Henrotin, Y; Hunter, D J; Jiang, G-L; Skou, S T; Wang, S; Schnitzer, T
2015-05-01
The goal of this document is to update the original OARSI recommendations specifically for the design, conduct, and reporting of clinical trials that target symptom or structure modification among individuals with knee osteoarthritis (OA). To develop recommendations for the design, conduct, and reporting of clinical trials for knee OA we initially drafted recommendations through an iterative process. Members of the working group included representatives from industry and academia. After the working group members reviewed a final draft, they scored the appropriateness for recommendations. After the members voted we calculated the median score among the nine members of the working group who completed the score. The document includes 25 recommendations regarding randomization, blocking and stratification, blinding, enhancing accuracy of patient-reported outcomes (PRO), selecting a study population and index knee, describing interventions, patient-reported and physical performance measures, structural outcome measures, biochemical biomarkers, and reporting recommendations. In summary, the working group identified 25 recommendations that represent the current best practices regarding clinical trials that target symptom or structure modification among individuals with knee OA. These updated recommendations incorporate novel technologies (e.g., magnetic resonance imaging (MRI)) and strategies to address the heterogeneity of knee OA. Copyright © 2015 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.
Tolerance of beta blocked hypertensives during orthostatic and altitude stress.
DOT National Transportation Integrated Search
1992-04-01
To evaluate the effects of orthostatic, altitude, and pharmacologic stresses upon civil aviation-specific performance, a double-blind, randomized, crossover trial of atenolol, 100mg, was designed and executed. Hypertensive males are females qualifyin...
A Simulation Study of Methods for Selecting Subgroup-Specific Doses in Phase I Trials
Morita, Satoshi; Thall, Peter F.; Takeda, Kentaro
2016-01-01
Summary Patient heterogeneity may complicate dose-finding in phase I clinical trials if the dose-toxicity curves differ between subgroups. Conducting separate trials within subgroups may lead to infeasibly small sample sizes in subgroups having low prevalence. Alternatively, it is not obvious how to conduct a single trial while accounting for heterogeneity. To address this problem, we consider a generalization of the continual reassessment method (O’Quigley, et al., 1990) based on a hierarchical Bayesian dose-toxicity model that borrows strength between subgroups under the assumption that the subgroups are exchangeable. We evaluate a design using this model that includes subgroup-specific dose selection and safety rules. A simulation study is presented that includes comparison of this method to three alternative approaches, based on non-hierarchical models, that make different types of assumptions about within-subgroup dose-toxicity curves. The simulations show that the hierarchical model-based method is recommended in settings where the dose-toxicity curves are exchangeable between subgroups. We present practical guidelines for application, and provide computer programs for trial simulation and conduct. PMID:28111916
Clemons, Mark; Russell, Kent; Costa, Luis; Addison, Christina L
2012-07-01
Bisphosphonate therapy has revolutionized the care of patients with metastatic bone disease. With its demonstrated activity and anti-tumour effects in preclinical studies it was natural to transition these agents to testing in the adjuvant setting. Surprisingly, the results of adjuvant breast cancer trials have shown either modest or no benefit or even harm. We sought to explore whether there were specific patient cohorts or treatment strategies that were most likely to benefit from adjuvant bisphosphonate therapy. We compared trial designs, patient characteristics and outcomes from the six published and two presented randomized adjuvant bisphosphonate trials. Differences in trial design and patient populations make direct comparisons complicated. The most efficacious use of adjuvant bisphosphonates appears to be in patients with either biopsy evidence of osseous micrometastases, were post-menopausal or had estrogen receptor-positive tumours. Despite tremendous optimism regarding adjuvant bisphosphonate therapy, results from large trials are conflicting. Further investigation into factors influencing response to bisphosphonate treatment or selection of appropriate sub-groups of patients with desirable response characteristics is warranted.
Comparison of 3 Methods to Assess Urine Specific Gravity in Collegiate Wrestlers.
Stuempfle, Kristin J.; Drury, Daniel G.
2003-12-01
OBJECTIVE: To investigate the reliability and validity of refractometry, hydrometry, and reagent strips in assessing urine specific gravity in collegiate wrestlers. DESIGN AND SETTING: We assessed the reliability of refractometry, hydrometry, and reagent strips between 2 trials and among 4 testers. The validity of hydrometry and reagent strips was assessed by comparison with refractometry, the criterion measure for urine specific gravity. SUBJECTS: Twenty-one National Collegiate Athletic Association Division III collegiate wrestlers provided fresh urine samples. MEASUREMENTS: Four testers measured the specific gravity of each urine sample 6 times: twice by refractometry, twice by hydrometry, and twice by reagent strips. RESULTS: Refractometer measurements were consistent between trials (R =.998) and among testers; hydrometer measurements were consistent between trials (R =.987) but not among testers; and reagent-strip measurements were not consistent between trials or among testers. Hydrometer (1.018 +/- 0.006) and reagent-strip (1.017 +/- 0.007) measurements were significantly higher than refractometer (1.015 +/- 0.006) measurements. Intraclass correlation coefficients were moderate between refractometry and hydrometry (R =.869) and low between refractometry and reagent strips (R =.573). The hydrometer produced 28% false positives and 2% false negatives, and reagent strips produced 15% false positives and 9% false negatives. CONCLUSIONS: Only the refractometer should be used to determine urine specific gravity in collegiate wrestlers during the weight-certification process.
Comparison of 3 Methods to Assess Urine Specific Gravity in Collegiate Wrestlers
Drury, Daniel G.
2003-01-01
Objective: To investigate the reliability and validity of refractometry, hydrometry, and reagent strips in assessing urine specific gravity in collegiate wrestlers. Design and Setting: We assessed the reliability of refractometry, hydrometry, and reagent strips between 2 trials and among 4 testers. The validity of hydrometry and reagent strips was assessed by comparison with refractometry, the criterion measure for urine specific gravity. Subjects: Twenty-one National Collegiate Athletic Association Division III collegiate wrestlers provided fresh urine samples. Measurements: Four testers measured the specific gravity of each urine sample 6 times: twice by refractometry, twice by hydrometry, and twice by reagent strips. Results: Refractometer measurements were consistent between trials (R = .998) and among testers; hydrometer measurements were consistent between trials (R = .987) but not among testers; and reagent-strip measurements were not consistent between trials or among testers. Hydrometer (1.018 ± 0.006) and reagent-strip (1.017 ± 0.007) measurements were significantly higher than refractometer (1.015 ± 0.006) measurements. Intraclass correlation coefficients were moderate between refractometry and hydrometry (R = .869) and low between refractometry and reagent strips (R = .573). The hydrometer produced 28% false positives and 2% false negatives, and reagent strips produced 15% false positives and 9% false negatives. Conclusions: Only the refractometer should be used to determine urine specific gravity in collegiate wrestlers during the weight-certification process. PMID:14737213
Lu, Xi; Nahum-Shani, Inbal; Kasari, Connie; Lynch, Kevin G.; Oslin, David W.; Pelham, William E.; Fabiano, Gregory; Almirall, Daniel
2016-01-01
A dynamic treatment regime (DTR) is a sequence of decision rules, each of which recommends a treatment based on a patient’s past and current health status. Sequential, multiple assignment, randomized trials (SMARTs) are multi-stage trial designs that yield data specifically for building effective DTRs. Modeling the marginal mean trajectories of a repeated-measures outcome arising from a SMART presents challenges, because traditional longitudinal models used for randomized clinical trials do not take into account the unique design features of SMART. We discuss modeling considerations for various forms of SMART designs, emphasizing the importance of considering the timing of repeated measures in relation to the treatment stages in a SMART. For illustration, we use data from three SMART case studies with increasing level of complexity, in autism, child attention deficit hyperactivity disorder (ADHD), and adult alcoholism. In all three SMARTs we illustrate how to accommodate the design features along with the timing of the repeated measures when comparing DTRs based on mean trajectories of the repeated-measures outcome. PMID:26638988
Lu, Xi; Nahum-Shani, Inbal; Kasari, Connie; Lynch, Kevin G; Oslin, David W; Pelham, William E; Fabiano, Gregory; Almirall, Daniel
2016-05-10
A dynamic treatment regime (DTR) is a sequence of decision rules, each of which recommends a treatment based on a patient's past and current health status. Sequential, multiple assignment, randomized trials (SMARTs) are multi-stage trial designs that yield data specifically for building effective DTRs. Modeling the marginal mean trajectories of a repeated-measures outcome arising from a SMART presents challenges, because traditional longitudinal models used for randomized clinical trials do not take into account the unique design features of SMART. We discuss modeling considerations for various forms of SMART designs, emphasizing the importance of considering the timing of repeated measures in relation to the treatment stages in a SMART. For illustration, we use data from three SMART case studies with increasing level of complexity, in autism, child attention deficit hyperactivity disorder, and adult alcoholism. In all three SMARTs, we illustrate how to accommodate the design features along with the timing of the repeated measures when comparing DTRs based on mean trajectories of the repeated-measures outcome. Copyright © 2015 John Wiley & Sons, Ltd.
Roach, Kathryn E.; Tappen, Ruth M.; Kirk-Sanchez, Neva; Williams, Christine L.; Loewenstein, David
2011-01-01
Objective To determine whether an activity specific exercise program could improve ability to perform basic mobility activities in long-term care residents with Alzheimer disease (AD). Design Randomized, controlled, single-blinded clinical trial. Setting Residents of 7 long-term care facilities. Participants Eighty-two long-term care residents with mild to severe AD. Intervention An activity specific exercise program was compared to a walking program and to an attention control. Measurements Ability to perform bed mobility and transfers were assessed using the subscales of the Acute Care Index of Function; functional mobility was measured using the 6-Minute Walk test. Results Subjects receiving the activity specific exercise program improved in ability to perform transfers, whereas subjects in the other 2 groups declined. PMID:21937893
Morey, Candice C; Miron, Monica D
2016-12-01
Among models of working memory, there is not yet a consensus about how to describe functions specific to storing verbal or visual-spatial memories. We presented aural-verbal and visual-spatial lists simultaneously and sometimes cued one type of information after presentation, comparing accuracy in conditions with and without informative retro-cues. This design isolates interference due specifically to maintenance, which appears most clearly in the uncued trials, from interference due to encoding, which occurs in all dual-task trials. When recall accuracy was comparable between tasks, we found that spatial memory was worse in uncued than in retro-cued trials, whereas verbal memory was not. Our findings bolster proposals that maintenance of spatial serial order, like maintenance of visual materials more broadly, relies on general rather than specialized resources, while maintenance of verbal sequences may rely on domain-specific resources. We argue that this asymmetry should be explicitly incorporated into models of working memory. (PsycINFO Database Record (c) 2016 APA, all rights reserved).
Naydeck, B L; Sutton-Tyrrell, K; Burek, K; Sopko, G S
1996-06-01
Efficient communication is a challenge for the many operating components of a multicenter randomized clinical trial. Traditional management theory states that communications generally flow along a path established by a hierarchical organizational structure. A multicenter clinical trial does not fit traditional organizational models well and requires modification of traditional communication techniques. While the scientific community typically views a clinical trial as one large and cohesive enterprise, at each site the trial may actually be conducted as a small project related to the medical specialty of the investigator. Therefore overall trial management must be accomplished through collaboration rather than through direct management. In the Bypass Angioplasty Revascularization Investigation (BARI), the BARI clinical coordinating center has designed and utilized several mechanisms that facilitate effective communication and administrative control of a multicenter clinical trial. These mechanisms provide a framework of communication techniques that accommodate the specific needs of a complex organization.
Weinstein, Philip; Milgrom, Peter; Riedy, Christine A; Mancl, Lloyd A; Garson, Gayle; Huebner, Colleen E; Smolen, Darlene; Sutherland, Marilynn; Nykamp, Ann
2014-02-24
Fidelity assessments are integral to intervention research but few published trials report these processes in detail. We included plans for fidelity monitoring in the design of a community-based intervention trial. The study design was a randomized clinical trial of an intervention provided to low-income women to increase utilization of dental care during pregnancy (mother) or the postpartum (child) period. Group assignment followed a 2 × 2 factorial design in which participants were randomly assigned to receive either brief Motivational Interviewing (MI) or Health Education (HE) during pregnancy (prenatal) and then randomly reassigned to one of these groups for the postpartum intervention. The study setting was four county health departments in rural Oregon State, USA. Counseling was standardized using a step-by-step manual. Counselors were trained to criteria prior to delivering the intervention and fidelity monitoring continued throughout the implementation period based on audio recordings of counselor-participant sessions. The Yale Adherence and Competence Scale (YACS), modified for this study, was used to code the audio recordings of the counselors' delivery of both the MI and HE interventions. Using Interclass Correlation Coefficients totaling the occurrences of specific MI counseling behaviors, ICC for prenatal was .93, for postpartum the ICC was .75. Participants provided a second source of fidelity data. As a second source of fidelity data, the participants completed the Feedback Questionnaire that included ratings of their satisfaction with the counselors at the completion of the prenatal and post-partum interventions. Coding indicated counselor adherence to MI protocol and variation among counselors in the use of MI skills in the MI condition. Almost no MI behaviors were found in the HE condition. Differences in the length of time to deliver intervention were found; as expected, the HE intervention took less time. There were no differences between the overall participants' satisfaction ratings of the HE and MI sessions by individual counselor or overall (p > .05). Trial design, protocol specification, training, and continuous supervision led to a high degree of treatment fidelity for the counseling interventions in this randomized clinical trial and will increase confidence in the interpretation of the trial findings.
2013-01-01
Background TREFAMS is an acronym for TReating FAtigue in Multiple Sclerosis, while ACE refers to the rehabilitation treatment methods under study, that is, Aerobic training, Cognitive behavioural therapy, and Energy conservation management. The TREFAMS-ACE research programme consists of four studies and has two main objectives: (1) to assess the effectiveness of three different rehabilitation treatment strategies in reducing fatigue and improving societal participation in patients with MS; and (2) to study the neurobiological mechanisms of action that underlie treatment effects and MS-related fatigue in general. Methods/Design Ambulatory patients (n = 270) suffering from MS-related fatigue will be recruited to three single-blinded randomised clinical trials (RCTs). In each RCT, 90 patients will be randomly allocated to the trial-specific intervention or to a low-intensity intervention that is the same for all RCTs. This low-intensity intervention consists of three individual consultations with a specialised MS-nurse. The trial-specific interventions are Aerobic Training, Cognitive Behavioural Therapy, and Energy Conservation Management. These interventions consist of 12 individual therapist-supervised sessions with additional intervention-specific home exercises. The therapy period lasts 16 weeks. All RCTs have the same design and the same primary outcome measures: fatigue - measured with the Checklist Individual Strength, and participation - measured with the Impact on Participation and Autonomy questionnaire. Outcomes will be assessed 1 week prior to, and at 0, 8, 16, 26 and 52 weeks after randomisation. The assessors will be blinded to allocation. Pro- and anti-inflammatory cytokines in serum, salivary cortisol, physical fitness, physical activity, coping, self-efficacy, illness cognitions and other determinants will be longitudinally measured in order to study the neurobiological mechanisms of action. Discussion The TREFAMS-ACE programme is unique in its aim to assess the effectiveness of three rehabilitation treatments. The programme will provide important insights regarding the most effective treatment for MS-related fatigue and the mechanisms that underlie treatment response. A major strength of the programme is that the design involves three almost identical RCTs, enabling a close comparison of the treatment strategies and a strong overall meta-analysis. The results will also support clinical practice guidelines for the treatment of MS-related fatigue. Trial registrations Current Controlled Trials ISRCTN69520623, ISRCTN58583714, and ISRCTN82353628 PMID:23938046
Hernán, Miguel A; Sauer, Brian C; Hernández-Díaz, Sonia; Platt, Robert; Shrier, Ian
2016-11-01
Many analyses of observational data are attempts to emulate a target trial. The emulation of the target trial may fail when researchers deviate from simple principles that guide the design and analysis of randomized experiments. We review a framework to describe and prevent biases, including immortal time bias, that result from a failure to align start of follow-up, specification of eligibility, and treatment assignment. We review some analytic approaches to avoid these problems in comparative effectiveness or safety research. Copyright © 2016 Elsevier Inc. All rights reserved.
Evaluation of agile designs in first-in-human (FIH) trials--a simulation study.
Perlstein, Itay; Bolognese, James A; Krishna, Rajesh; Wagner, John A
2009-12-01
The aim of the investigation was to evaluate alternatives to standard first-in-human (FIH) designs in order to optimize the information gained from such studies by employing novel agile trial designs. Agile designs combine adaptive and flexible elements to enable optimized use of prior information either before and/or during conduct of the study to seamlessly update the study design. A comparison of the traditional 6 + 2 (active + placebo) subjects per cohort design with alternative, reduced sample size, agile designs was performed by using discrete event simulation. Agile designs were evaluated for specific adverse event models and rates as well as dose-proportional, saturated, and steep-accumulation pharmacokinetic profiles. Alternative, reduced sample size (hereafter referred to as agile) designs are proposed for cases where prior knowledge about pharmacokinetics and/or adverse event relationships are available or appropriately assumed. Additionally, preferred alternatives are proposed for a general case when prior knowledge is limited or unavailable. Within the tested conditions and stated assumptions, some agile designs were found to be as efficient as traditional designs. Thus, simulations demonstrated that the agile design is a robust and feasible approach to FIH clinical trials, with no meaningful loss of relevant information, as it relates to PK and AE assumptions. In some circumstances, applying agile designs may decrease the duration and resources required for Phase I studies, increasing the efficiency of early clinical development. We highlight the value and importance of useful prior information when specifying key assumptions related to safety, tolerability, and PK.
Yao, Chu K; Gibson, Peter R; Shepherd, Susan J
2013-05-01
Clear guiding principles for the design and conduct of dietary intervention trials in functional gastrointestinal disorders (FGID) are lacking. This narrative review examines the specific challenges associated with the design and reporting in dietary intervention trials. Dietary intervention trials need to address the collinearity between food, nutrients, and bioactive components that obscure the relationship between food and their effects in the gut. Randomized, double-blinded, placebo-controlled studies remain the gold standard for dietary trials, but are limited by difficulties in adequate masking of study food or inappropriate choice of placebo food/diets. Provision of study diets as the preferred delivery method can somewhat address these limitations, although allowing good adherence compared with education-based dietary interventions. Issues associated with participant expectancies and dietary behaviors can alter the true effectiveness of a diet. In addition, failure to adjust for or report baseline intake of nutrients of interest can reduce their magnitude of benefit. Bias in subjective reports and choice of measurement tools can preclude accurate assessment of food-intake data. In the design of elimination and rechallenge studies, sufficient time period and adequate exclusion of dietary triggers are essential to ensure symptoms are well-controlled before rechallenging. The route and frequency of challenging, design of test food, and/or placebo should match the aims of the rechallenge phase. Long-term efficacy data of such therapeutic diets has been poorly documented in most studies. Standardized guidelines that address many of the challenges outlined above are suggested to strengthen the quality of evidence for dietary therapies in FGID.
Ambrosius, Walter T; Polonsky, Tamar S; Greenland, Philip; Goff, David C; Perdue, Letitia H; Fortmann, Stephen P; Margolis, Karen L; Pajewski, Nicholas M
2012-04-01
Although observational evidence has suggested that the measurement of coronary artery calcium (CAC) may improve risk stratification for cardiovascular events and thus help guide the use of lipid-lowering therapy, this contention has not been evaluated within the context of a randomized trial. The Value of Imaging in Enhancing the Wellness of Your Heart (VIEW) trial is proposed as a randomized study in participants at low intermediate risk of future coronary heart disease (CHD) events to evaluate whether CAC testing leads to improved patient outcomes. To describe the challenges encountered in designing a prototypical screening trial and to examine the impact of uncertainty on power. The VIEW trial was designed as an effectiveness clinical trial to examine the benefit of CAC testing to guide therapy on a primary outcome consisting of a composite of nonfatal myocardial infarction, probable or definite angina with revascularization, resuscitated cardiac arrest, nonfatal stroke (not transient ischemic attack (TIA)), CHD death, stroke death, other atherosclerotic death, or other cardiovascular disease (CVD) death. Many critical choices were faced in designing the trial, including (1) the choice of primary outcome, (2) the choice of therapy, (3) the target population with corresponding ethical issues, (4) specifications of assumptions for sample size calculations, and (5) impact of uncertainty in these assumptions on power/sample size determination. We have proposed a sample size of 30,000 (800 events), which provides 92.7% power. Alternatively, sample sizes of 20,228 (539 events), 23,138 (617 events), and 27,078 (722 events) provide 80%, 85%, and 90% power. We have also allowed for uncertainty in our assumptions by computing average power integrated over specified prior distributions. This relaxation of specificity indicates a reduction in power, dropping to 89.9% (95% confidence interval (CI): 89.8-89.9) for a sample size of 30,000. Samples sizes of 20,228, 23,138, and 27,078 provide power of 78.0% (77.9-78.0), 82.5% (82.5-82.6), and 87.2% (87.2-87.3), respectively. These power estimates are dependent on form and parameters of the prior distributions. Despite the pressing need for a randomized trial to evaluate the utility of CAC testing, conduct of such a trial requires recruiting a large patient population, making efficiency of critical importance. The large sample size is primarily due to targeting a study population at relatively low risk of a CVD event. Our calculations also illustrate the importance of formally considering uncertainty in power calculations of large trials as standard power calculations may tend to overestimate power.
Ambrosius, Walter T.; Polonsky, Tamar S.; Greenland, Philip; Goff, David C.; Perdue, Letitia H.; Fortmann, Stephen P.; Margolis, Karen L.; Pajewski, Nicholas M.
2014-01-01
Background Although observational evidence has suggested that the measurement of CAC may improve risk stratification for cardiovascular events and thus help guide the use of lipid-lowering therapy, this contention has not been evaluated within the context of a randomized trial. The Value of Imaging in Enhancing the Wellness of Your Heart (VIEW) trial is proposed as a randomized study in participants at low intermediate risk of future coronary heart disease (CHD) events to evaluate whether coronary artery calcium (CAC) testing leads to improved patient outcomes. Purpose To describe the challenges encountered in designing a prototypical screening trial and to examine the impact of uncertainty on power. Methods The VIEW trial was designed as an effectiveness clinical trial to examine the benefit of CAC testing to guide therapy on a primary outcome consisting of a composite of non-fatal myocardial infarction, probable or definite angina with revascularization, resuscitated cardiac arrest, non-fatal stroke (not transient ischemic attack (TIA)), CHD death, stroke death, other atherosclerotic death, or other cardiovascular disease (CVD) death. Many critical choices were faced in designing the trial, including: (1) the choice of primary outcome, (2) the choice of therapy, (3) the target population with corresponding ethical issues, (4) specifications of assumptions for sample size calculations, and (5) impact of uncertainty in these assumptions on power/sample size determination. Results We have proposed a sample size of 30,000 (800 events) which provides 92.7% power. Alternatively, sample sizes of 20,228 (539 events), 23,138 (617 events) and 27,078 (722 events) provide 80, 85, and 90% power. We have also allowed for uncertainty in our assumptions by computing average power integrated over specified prior distributions. This relaxation of specificity indicates a reduction in power, dropping to 89.9% (95% confidence interval (CI): 89.8 to 89.9) for a sample size of 30,000. Samples sizes of 20,228, 23,138, and 27,078 provide power of 78.0% (77.9 to 78.0), 82.5% (82.5 to 82.6), and 87.2% (87.2 to 87.3), respectively. Limitations These power estimates are dependent on form and parameters of the prior distributions. Conclusions Despite the pressing need for a randomized trial to evaluate the utility of CAC testing, conduct of such a trial requires recruiting a large patient population, making efficiency of critical importance. The large sample size is primarily due to targeting a study population at relatively low risk of a CVD event. Our calculations also illustrate the importance of formally considering uncertainty in power calculations of large trials as standard power calculations may tend to overestimate power. PMID:22333998
Greenfield, Shelly F.; Rosa, Carmen; Putnins, Susan I.; Green, Carla A.; Brooks, Audrey J.; Calsyn, Donald A.; Cohen, Lisa R.; Erickson, Sarah; Gordon, Susan M.; Haynes, Louise; Killeen, Therese; Miele, Gloria; Tross, Susan; Winhusen, Theresa
2011-01-01
Background The NIDA National Drug Abuse Treatment Clinical Trials Network (CTN) was established to foster translation of research into practice in substance abuse treatment settings. The CTN provides a unique opportunity to examine in multi-site, translational clinical trials, the outcomes of treatment interventions targeting vulnerable sub-groups of women; the comparative effectiveness of gender-specific protocols to reduce risk behaviors; and gender differences in clinical outcomes. Objectives To review gender-related findings from published CTN clinical trials and related studies from January, 2000 through March, 2010. Methods CTN studies were selected for review if they focused on treatment outcomes or services for special populations of women with substance use disorders (SUDs) including those with trauma histories, pregnancy, co-occurring eating and other psychiatric disorders and HIV risk behaviors; or implemented gender-specific protocols. Results The CTN has randomized 11,500 participants (41% women) across 200 clinics in 24 randomized clinical trials in community settings, of which 4 have been gender-specific. This paper summarizes gender-related findings from CTN clinical trials and related studies, focusing on trauma histories, pregnancy, co-occurring eating and other psychiatric disorders, and HIV risk behaviors. Conclusions These published studies have expanded the evidence base regarding interventions for vulnerable groups of women with SUDs as well as gender-specific interventions to reduce HIV risk behaviors in substance using men and women. The results also underscore the complexity of accounting for gender in the design of clinical trials and analysis of results. Scientific Relevance To fully understand the relevance of gender-specific moderators and mediators of outcome, it is essential that future translational studies adopt more sophisticated approaches to understanding and measuring gender-relevant factors and plan sample sizes that are adequate to support more nuanced analytic methods. PMID:21854272
Jäger, Susanne; Müller, Kai W; Ruckes, Christian; Wittig, Tobias; Batra, Anil; Musalek, Michael; Mann, Karl; Wölfling, Klaus; Beutel, Manfred E
2012-04-27
In the last few years, excessive internet use and computer gaming have increased dramatically. Salience, mood modification, tolerance, withdrawal symptoms, conflict, and relapse have been defined as diagnostic criteria for internet addiction (IA) and computer addiction (CA) in the scientific community. Despite a growing number of individuals seeking help, there are no specific treatments of established efficacy. This clinical trial aims to determine the effect of the disorder-specific manualized short-term treatment of IA/CA (STICA). The cognitive behavioural treatment combines individual and group interventions with a total duration of 4 months. Patients will be randomly assigned to STICA treatment or to a wait list control group. Reliable and valid measures of IA/CA and co-morbid mental symptoms (for example social anxiety, depression) will be assessed prior to the beginning, in the middle, at the end, and 6 months after completion of treatment. A treatment of IA/CA will establish efficacy and is desperately needed. As this is the first trial to determine efficacy of a disorder specific treatment, a wait list control group will be implemented. Pros and cons of the design were discussed. ClinicalTrials (NCT01434589).
Decision aids for randomised controlled trials: a qualitative exploration of stakeholders’ views
Gillies, Katie; Skea, Zoë C; Campbell, Marion K
2014-01-01
Objectives To explore stakeholders’ perceptions of decision aids designed to support the informed consent decision-making process for randomised controlled trials. Design Qualitative semistructured interviews. Participants were provided with prototype trial decision aids in advance to stimulate discussion. Interviews were analysed using an established interpretive approach. Participants 23 stakeholders: Trial Managers (n=5); Research Nurses (n=5); Ethics Committee Chairs (n=5); patients (n=4) and Clinical Principal Investigators (n=4). Setting Embedded within two ongoing randomised controlled trials. All interviews conducted with UK-based participants. Results Certain key aspects (eg, values clarification exercises, presentation of probabilities, experiences of others and balance of options) in the prototype decision aids were perceived by all stakeholders as having a significant advantage (over existing patient information leaflets) in terms of supporting well informed appropriate decisions. However, there were some important differences between the stakeholder groups on specific content (eg, language used in the section on positive and negative features of taking part in a trial and the overall length of the trial decision aids). Generally the stakeholders believed trial decision aids have the potential to better engage potential participants in the decision-making process and allow them to make more personally relevant decisions about their participation. Conclusions Compared to existing patient information leaflets, stakeholders perceived decision aids for trial participation to have the potential to promote a more ‘informed’ decision-making process. Further efforts to develop, refine and formally evaluate trial decision aids should be explored. PMID:25138811
Siegfried, Elaine C; Jaworski, Jennifer C; Eichenfield, Lawrence F; Paller, Amy; Hebert, Adelaide A; Simpson, Eric L; Altman, Emily; Arena, Charles; Blauvelt, Andrew; Block, Julie; Boguniewicz, Mark; Chen, Suephy; Cordoro, Kelly; Hanna, Diane; Horii, Kimberly; Hultsch, Thomas; Lee, James; Leung, Donald Y; Lio, Peter; Milner, Joshua; Omachi, Theodore; Schneider, Christine; Schneider, Lynda; Sidbury, Robert; Smith, Timothy; Sugarman, Jeffrey; Taha, Sharif; Tofte, Susan; Tollefson, Megha; Tom, Wynnis L; West, Dennis P; Whitney, Lucinda; Zane, Lee
2018-05-01
Atopic dermatitis is the most common chronic skin disease, and it primarily affects children. Although atopic dermatitis (AD) has the highest effect on burden of skin disease, no high-level studies have defined optimal therapy for severe disease. Corticosteroids have been used to treat AD since the 1950s and remain the only systemic medication with Food and Drug Administration approval for this indication in children, despite published guidelines of care that recommend against this option. Several clinical trials with level 1 evidence have supported the use of topical treatments for mild to moderate atopic dermatitis in adults and children, but these trials have had little consistency in protocol design. Consensus recommendations will help standardize clinical development and trial design for children. The Food and Drug Administration issues guidance documents for industry as a source for "the Agency's current thinking on a particular subject." Although they are nonbinding, industry considers these documents to be the standard for clinical development and trial design. Our consensus group is the first to specifically address clinical trial design in this population. We developed a draft guidance document for industry, Developing Drugs for Treatment of Atopic Dermatitis in Children (≥3 months to <18 years of age). This draft guidance has been submitted to the Food and Drug Administration based on a provision in the Federal Register (Good Guidance Practices). © 2018 Wiley Periodicals, Inc.
Geographic Proximity and Racial Disparities in Cancer Clinical Trial Participation
Kanarek, Norma F.; Tsai, Hua-Ling; Metzger-Gaud, Sharon; Damron, Dorothy; Guseynova, Alla; Klamerus, Justin F.; Rudin, Charles M.
2011-01-01
This study assessed the effects of race and place of residence on clinical trial participation by patients seen at a designated NCI comprehensive cancer center. Clinical trial accrual to cancer case ratios were evaluated using a database of residents at the continental United States seen at The Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins from 2005 to 2007. Place of residence was categorized into 3 nonoverlapping geographic areas: Baltimore City, non–Baltimore City catchment area, and non–catchment area. Controlling for age, sex, county poverty level, and cancer site, significant race and place of residence differences were seen in therapeutic or nontherapeutic clinical trials participation. White non–Baltimore City catchment area residents, the designated reference group, achieved the highest participation rate. Although the test of interaction (control group compared with all others) was not significant, some race–geographic area group differences were detected. In therapeutic trials, most race–place of residence group levels were statistically lower and different from reference; in nontherapeutic trials, race-specific Baltimore City groups participated at levels similar to reference. Baltimore City residents had lower participation rates only in therapeutic trials, irrespective of race. County poverty level was not significant but was retained as a confounder. Place of residence and race were found to be significant predictors of participation in therapeutic and nontherapeutic clinical trials, although patterns differed somewhat between therapeutic and nontherapeutic trials. Clinical trial accruals are not uniform across age, sex, race, place of residence, cancer site, or trial type, underscoring that cancer centers must better understand their source patients to enhance clinical trial participation. PMID:21147901
Schieffelin, John; Moses, Lina M; Shaffer, Jeffrey; Goba, Augustine; Grant, Donald S
2015-01-01
The current Ebola outbreak in West Africa has affected more people than all previous outbreaks combined. The current diagnostic method of choice, quantitative polymerase chain reaction, requires specialized conditions as well as specially trained technicians. Insufficient testing capacity has extended the time from sample collection to results. These delays have led to further delays in the transfer and treatment to Ebola Treatment Units. A sensitive and specific point-of-care device that could be used reliably in low resource settings by healthcare workers with minimal training would increase the efficiency of triage and appropriate transfer of care. This article describes a study designed to validate the sensitivity and specificity of the ReEBOVTM RDT using venous whole blood and capillary blood obtained via fingerprick. We present the scientific and clinical rationale for the decisions made in the design of a diagnostic validation study to be conducted in an outbreak setting. The multi-site strategy greatly complicated implementation. In addition, a decrease in cases in one geographic area along with a concomitant increase in other areas made site selection challenging. Initiation of clinical trials during rapidly evolving outbreaks requires significant cooperation on a national level between research teams implementing studies and clinical care providers. Coordination and streamlining of approval process is essential if trials are to be implemented in a timely fashion. PMID:26768566
Montani, Veronica; De Filippo De Grazia, Michele; Zorzi, Marco
2014-01-01
A growing body of evidence suggests that action videogames could enhance a variety of cognitive skills and more specifically attention skills. The aim of this study was to develop a novel adaptive videogame to support the rehabilitation of the most common consequences of traumatic brain injury (TBI), that is the impairment of attention and executive functions. TBI patients can be affected by psychomotor slowness and by difficulties in dealing with distraction, maintain a cognitive set for a long time, processing different simultaneously presented stimuli, and planning purposeful behavior. Accordingly, we designed a videogame that was specifically conceived to activate those functions. Playing involves visuospatial planning and selective attention, active maintenance of the cognitive set representing the goal, and error monitoring. Moreover, different game trials require to alternate between two tasks (i.e., task switching) or to perform the two tasks simultaneously (i.e., divided attention/dual-tasking). The videogame is controlled by a multidimensional adaptive algorithm that calibrates task difficulty on-line based on a model of user performance that is updated on a trial-by-trial basis. We report simulations of user performance designed to test the adaptive game as well as a validation study with healthy participants engaged in a training protocol. The results confirmed the involvement of the cognitive abilities that the game is supposed to enhance and suggested that training improved attentional control during play.
Montani, Veronica; De Filippo De Grazia, Michele; Zorzi, Marco
2014-01-01
A growing body of evidence suggests that action videogames could enhance a variety of cognitive skills and more specifically attention skills. The aim of this study was to develop a novel adaptive videogame to support the rehabilitation of the most common consequences of traumatic brain injury (TBI), that is the impairment of attention and executive functions. TBI patients can be affected by psychomotor slowness and by difficulties in dealing with distraction, maintain a cognitive set for a long time, processing different simultaneously presented stimuli, and planning purposeful behavior. Accordingly, we designed a videogame that was specifically conceived to activate those functions. Playing involves visuospatial planning and selective attention, active maintenance of the cognitive set representing the goal, and error monitoring. Moreover, different game trials require to alternate between two tasks (i.e., task switching) or to perform the two tasks simultaneously (i.e., divided attention/dual-tasking). The videogame is controlled by a multidimensional adaptive algorithm that calibrates task difficulty on-line based on a model of user performance that is updated on a trial-by-trial basis. We report simulations of user performance designed to test the adaptive game as well as a validation study with healthy participants engaged in a training protocol. The results confirmed the involvement of the cognitive abilities that the game is supposed to enhance and suggested that training improved attentional control during play. PMID:24860529
Rautiainen, Susanne; Sesso, Howard D; Manson, JoAnn E
2017-12-29
Several bioactive compounds and nutrients in foods have physiological properties that are beneficial for human health. While nutrients typically have clear definitions with established levels of recommended intakes, bioactive compounds often lack such a definition. Although a food-based approach is often the optimal approach to ensure adequate intake of bioactives and nutrients, these components are also often produced as dietary supplements. However, many of these supplements are not sufficiently studied and have an unclear role in chronic disease prevention. Randomized trials are considered the gold standard of study designs, but have not been fully applied to understand the effects of bioactives and nutrients. We review the specific role of large-scale trials to test whether bioactives and nutrients have an effect on health outcomes through several crucial components of trial design, including selection of intervention, recruitment, compliance, outcome selection, and interpretation and generalizability of study findings. We will discuss these components in the context of two randomized clinical trials, the VITamin D and OmegA-3 TriaL (VITAL) and the COcoa Supplement and Multivitamin Outcomes Study (COSMOS). We will mainly focus on dietary supplements of bioactives and nutrients while also emphasizing the need for translation and integration with food-based trials that are of vital importance within nutritional research. Copyright © 2017. Published by Elsevier Ltd.
Antioxidants and cancer therapy: a systematic review.
Ladas, Elena J; Jacobson, Judith S; Kennedy, Deborah D; Teel, Katherine; Fleischauer, Aaron; Kelly, Kara M
2004-02-01
Many patients with cancer take antioxidant nutritional supplements during cancer treatment to alleviate treatment toxicities and to improve long-term outcomes, but little is known about the efficacy and safety of antioxidant use during cancer treatment. We reviewed English-language manuscripts published in the biomedical literature, reporting the results of observational studies of antioxidant status and cancer outcomes and of intervention trials of antioxidants among patients receiving chemotherapy with or without radiation for various malignancies. We searched the Medline database and the bibliographies of the retrieved manuscripts, reviews, and books on antioxidants and cancer. The retrieved studies are grouped by study design, malignancy, and end points. More than 100 citations were retrieved; 52 met our criteria, 31 were observational studies, and 21 were intervention trials. The studies varied in study design, timing of observation/intervention, intervention protocol, malignancy, and anticancer regimen. These inconsistencies preclude a definitive conclusion as to the effect of chemotherapy on antioxidant status in patients undergoing anticancer therapy. However, our review suggests that total antioxidant status (measured by total radical antioxidant parameter) declines during cancer treatment. Adequately powered trials or observational studies among patients with a specific cancer diagnosis receiving a specific treatment regimen are needed to address patients' and physicians' concerns regarding these associations.
Genetic potential of black bean genotypes with predictable behaviors in multienvironment trials.
Torga, P P; Melo, P G S; Pereira, H S; Faria, L C; Melo, L C
2016-10-24
The aim of this study was to evaluate the phenotypic stability and specific and broad adaptability of common black bean genotypes for the Central and Center-South regions of Brazil by using the Annicchiarico and AMMI (weighted average of absolute scores: WAAS, and weighted average of absolute scores and productivity: WAASP) methodologies. We carried out 69 trials, with 43 and 26 trials in the Central and Center-South regions, respectively. Thirteen genotypes were evaluated in a randomized block design with three replications, during the rainy, dry, and winter seasons in 2 years. To obtain estimates of specific adaptation, we analyzed the parameters for each method obtained in the two geographic regions separately. To estimate broad adaptation, we used the average of the parameters obtained from each region. The lines identified with high specific adaptation in each region were not the same based on the Annicchiarico and AMMI (WAAS) methodologies. It was not possible to identify the same genotypes with specific or broad stability by using these methods. By contrast, the Annicchiarico and AMMI (WAASP) methods presented very similar estimates of broad and specific adaptation. Based on these methods, the lines with more specific adaptation were CNFP 8000 and CNFP 7994, in the Central and Center-South regions, respectively, of which the CNFP 8000 line was more widely adapted.
Are You "Tilting at Windmills" or Undertaking a Valid Clinical Trial?
Zariffa, Jose; Kramer, John L.K.
2011-01-01
In this review, several aspects surrounding the choice of a therapeutic intervention and the conduct of clinical trials are discussed. Some of the background for why human studies have evolved to their current state is also included. Specifically, the following questions have been addressed: 1) What criteria should be used to determine whether a scientific discovery or invention is worthy of translation to human application? 2) What recent scientific advance warrants a deeper understanding of clinical trials by everyone? 3) What are the different types and phases of a clinical trial? 4) What characteristics of a human disorder should be noted, tracked, or stratified for a clinical trial and what inclusion /exclusion criteria are important to enrolling appropriate trial subjects? 5) What are the different study designs that can be used in a clinical trial program? 6) What confounding factors can alter the accurate interpretation of clinical trial outcomes? 7) What are the success rates of clinical trials and what can we learn from previous clinical trials? 8) What are the essential principles for the conduct of valid clinical trials? PMID:21786433
Management of functional dyspepsia: Unsolved problems and new perspectives.
Madisch, Ahmed; Miehlke, Stephan; Labenz, Joachim
2005-11-14
The common characteristic criteria of all functional gastrointestinal (GI) disorders are the persistence and recurrence of variable gastrointestinal symptoms that cannot be explained by any structural or biochemical abnormalities. Functional dyspepsia (FD) represents one of the important GI disorders in Western countries because of its remarkably high prevalence in general population and its impact on quality of life. Due to its dependence on both subjective determinants and diverse country-specific circumstances, the definition and management strategies of FD are still variably stated. Clinical trials with several drug classes (e.g., proton pump inhibitors, H2-blockers, prokinetic drugs) have been performed frequently without validated disease-specific test instruments for the outcome measurements. Therefore, the interpretation of such trials remains difficult and controversial with respect to comparability and evaluation of drug efficacy, and definite conclusions can be drawn neither for diagnostic management nor for efficacious drug therapy so far. In view of these unsolved problems, guidelines both on the clinical management of FD and on the performance of clinical trials are needed. In recent years, increasing research work has been done in this area. Clinical trials conducted in adequately diagnosed patients that provided validated outcome measurements may result in better insights leading to more effective treatment strategies. Encouraging perspectives have been recently performed by methodologically well-designed treatment studies with herbal drug preparations. Herbal drugs, given their proven efficacy in clinical trials, offer a safe therapeutic alternative in the treatment of FD which is often favored by both patients and physicians. A fixed combination of peppermint oil and caraway oil in patients suffering from FD could be proven effective by well-designed clinical trials.
Evans, M Blair; McGuckin, Matthew; Gainforth, Heather L; Bruner, Mark W; Côté, Jean
2015-07-01
Although evidence supports the effectiveness of interpersonal Coach Development Programmes (CDPs), which are designed to foster coach-athlete relationships, an intervention's impact is shaped by numerous factors over and above effectiveness. The purpose of this systematic review was to examine the extent that published articles describing interpersonal CDP trials reported on indicators of internal and external validity, as conceptualised in the RE-AIM framework (ie, Reach, Effectiveness, Adoption, Implementation and Maintenance). The search strategy was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines, involving a database search and supplemental manual search of key articles and journals. After initial screening, the full-text search strategy involved identifying articles describing CDP trials and then selecting a specific subgroup of articles involving interpersonal CDP trials and excluding ineligible articles. Resulting trials were coded using a 47-item sport coaching adaptation of the RE-AIM coding sheet. 17 published articles met eligibility criteria, representing 10 distinct CDP trials. After attaining coder agreement, global ratings of RE-AIM indicators within interpersonal CDP trials ranged from the low to moderate quality. Whereas indicators of effectiveness and implementation were reported to some extent across all studies, maintenance within sport organisations and a number of specific indicators from across dimensions were rarely reported. These findings inform the future design and evaluation of CDPs that have the potential to be adopted in numerous settings and reach athletes and coaches who can most benefit. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.
Achieving consensus for clinical trials
Blakeley, Jaishri O.; Dombi, Eva; Fisher, Michael J.; Hanemann, C. Oliver; Walsh, Karin S.; Wolters, Pamela L.; Widemann, Brigitte C.
2013-01-01
The neurofibromatoses (NF)—including neurofibromatosis 1 (NF1), neurofibromatosis 2 (NF2), and schwannomatosis—are related tumor-suppressor syndromes characterized by a predisposition to multiple tumor types and other disease manifestations, which often result in functional disability, reduced quality of life, pain, and, in some cases, malignancy. With increasing knowledge of the biology and pathogenesis of NF, clinical trials with targeted agents directed at NF tumors have become available. Most clinical trials for patients with NF have used designs and endpoints similar to oncology trials. However, differences in the disease manifestations and natural history of NF (compared to cancers) require the development of new designs and endpoints to perform meaningful NF clinical trials. The Response Evaluation in Neurofibromatosis and Schwannomatosis (REiNS) International Collaboration was established in 2011 at the Children's Tumor Foundation meeting to achieve consensus within the NF community about the design of future clinical trials, with a specific emphasis on endpoints. The REiNS Collaboration includes 7 working groups that focus on imaging of tumor response; functional, visual, patient-reported, and neurocognitive outcomes; whole-body MRI; and disease biomarkers. This supplement includes the first series of recommendations by the REiNS Collaboration. The hope is that these recommendations will be used by members of the group and by researchers outside of the REiNS International Collaboration to standardize the measurement of outcomes and thus improve clinical trials for patients with NF. Ultimately, we plan to engage industry partners and national regulatory agencies in this process to facilitate the approval of drugs for patients with NF. PMID:24249801
Howard, Louise; de Salis, Isabel; Tomlin, Zelda; Thornicroft, Graham; Donovan, Jenny
2009-01-01
Background Under-recruitment to randomised controlled trials (RCTs) is often problematic and there may be particular difficulties in recruiting patients with severe mental illness. Aim To evaluate reasons for under-recruitment in an RCT of patients with severe mental illness Methods Qualitative study during the recruitment phase of an RCT of supported employment. Trial staff and recruiting clinicians were interviewed. Data were analyzed thematically using constant comparative techniques. Results Recruitment rates were low. Five main reasons for recruitment difficulties were found. These included: (i) misconceptions about trials, (ii) lack of equipoise, (iii) misunderstanding of the trial arms, (iv) variable interpretations of eligibility criteria, (v) paternalism. Conclusion Reasons for recruitment difficulties in trials involving patients with severe mental illness include issues that occur in trials in general, but others are more specific to these patients. Clinician and patient involvement in the study design may improve recruitment in future similar trials. PMID:18718555
Arabi, Yaseen M; Alothman, Adel; Balkhy, Hanan H; Al-Dawood, Abdulaziz; AlJohani, Sameera; Al Harbi, Shmeylan; Kojan, Suleiman; Al Jeraisy, Majed; Deeb, Ahmad M; Assiri, Abdullah M; Al-Hameed, Fahad; AlSaedi, Asim; Mandourah, Yasser; Almekhlafi, Ghaleb A; Sherbeeni, Nisreen Murad; Elzein, Fatehi Elnour; Memon, Javed; Taha, Yusri; Almotairi, Abdullah; Maghrabi, Khalid A; Qushmaq, Ismael; Al Bshabshe, Ali; Kharaba, Ayman; Shalhoub, Sarah; Jose, Jesna; Fowler, Robert A; Hayden, Frederick G; Hussein, Mohamed A
2018-01-30
It had been more than 5 years since the first case of Middle East Respiratory Syndrome coronavirus infection (MERS-CoV) was recorded, but no specific treatment has been investigated in randomized clinical trials. Results from in vitro and animal studies suggest that a combination of lopinavir/ritonavir and interferon-β1b (IFN-β1b) may be effective against MERS-CoV. The aim of this study is to investigate the efficacy of treatment with a combination of lopinavir/ritonavir and recombinant IFN-β1b provided with standard supportive care, compared to treatment with placebo provided with standard supportive care in patients with laboratory-confirmed MERS requiring hospital admission. The protocol is prepared in accordance with the SPIRIT (Standard Protocol Items: Recommendations for Interventional Trials) guidelines. Hospitalized adult patients with laboratory-confirmed MERS will be enrolled in this recursive, two-stage, group sequential, multicenter, placebo-controlled, double-blind randomized controlled trial. The trial is initially designed to include 2 two-stage components. The first two-stage component is designed to adjust sample size and determine futility stopping, but not efficacy stopping. The second two-stage component is designed to determine efficacy stopping and possibly readjustment of sample size. The primary outcome is 90-day mortality. This will be the first randomized controlled trial of a potential treatment for MERS. The study is sponsored by King Abdullah International Medical Research Center, Riyadh, Saudi Arabia. Enrollment for this study began in November 2016, and has enrolled thirteen patients as of Jan 24-2018. ClinicalTrials.gov, ID: NCT02845843 . Registered on 27 July 2016.
Gilbert, Peter B.; Juraska, Michal; deCamp, Allan C.; Karuna, Shelly; Edupuganti, Srilatha; Mgodi, Nyaradzo; Donnell, Deborah J.; Bentley, Carter; Sista, Nirupama; Andrew, Philip; Isaacs, Abby; Huang, Yunda; Zhang, Lily; Capparelli, Edmund; Kochar, Nidhi; Wang, Jing; Eshleman, Susan H.; Mayer, Kenneth H.; Magaret, Craig A.; Hural, John; Kublin, James G.; Gray, Glenda; Montefiori, David C.; Gomez, Margarita M.; Burns, David N.; McElrath, Julie; Ledgerwood, Julie; Graham, Barney S.; Mascola, John R.; Cohen, Myron; Corey, Lawrence
2017-01-01
Background Anti-HIV-1 broadly neutralizing antibodies (bnAbs) have been developed as potential agents for prevention of HIV-1 infection. The HIV Vaccine Trials Network and the HIV Prevention Trials Network are conducting the Antibody Mediated Prevention (AMP) trials to assess whether, and how, intravenous infusion of the anti-CD4 binding site bnAb, VRC01, prevents HIV-1 infection. These are the first test-of-concept studies to assess HIV-1 bnAb prevention efficacy in humans. Methods The AMP trials are two parallel phase 2b HIV-1 prevention efficacy trials conducted in two cohorts: 2700 HIV-uninfected men and transgender persons who have sex with men in the United States, Peru, Brazil, and Switzerland; and 1500 HIV-uninfected sexually active women in seven countries in sub-Saharan Africa. Participants are randomized 1:1:1 to receive an intravenous infusion of 10 mg/kg VRC01, 30 mg/kg VRC01, or a control preparation every 8 weeks for a total of 10 infusions. Each trial is designed (1) to assess overall prevention efficacy (PE) pooled over the two VRC01 dose groups vs. control and (2) to assess VRC01 dose and laboratory markers as correlates of protection (CoPs) against overall and genotype- and phenotype-specific infection. Results Each AMP trial is designed to have 90% power to detect PE > 0% if PE is ≥ 60%. The AMP trials are also designed to identify VRC01 properties (i.e., concentration and effector functions) that correlate with protection and to provide insight into mechanistic CoPs. CoPs are assessed using data from breakthrough HIV-1 infections, including genetic sequences and sensitivities to VRC01-mediated neutralization and Fc effector functions. Conclusions The AMP trials test whether VRC01 can prevent HIV-1 infection in two study populations. If affirmative, they will provide information for estimating the optimal dosage of VRC01 (or subsequent derivatives) and identify threshold levels of neutralization and Fc effector functions associated with high-level protection, setting a benchmark for future vaccine evaluation and constituting a bridge to other bnAb approaches for HIV-1 prevention. PMID:29218117
Gilbert, Peter B; Juraska, Michal; deCamp, Allan C; Karuna, Shelly; Edupuganti, Srilatha; Mgodi, Nyaradzo; Donnell, Deborah J; Bentley, Carter; Sista, Nirupama; Andrew, Philip; Isaacs, Abby; Huang, Yunda; Zhang, Lily; Capparelli, Edmund; Kochar, Nidhi; Wang, Jing; Eshleman, Susan H; Mayer, Kenneth H; Magaret, Craig A; Hural, John; Kublin, James G; Gray, Glenda; Montefiori, David C; Gomez, Margarita M; Burns, David N; McElrath, Julie; Ledgerwood, Julie; Graham, Barney S; Mascola, John R; Cohen, Myron; Corey, Lawrence
2017-01-01
Anti-HIV-1 broadly neutralizing antibodies (bnAbs) have been developed as potential agents for prevention of HIV-1 infection. The HIV Vaccine Trials Network and the HIV Prevention Trials Network are conducting the Antibody Mediated Prevention (AMP) trials to assess whether, and how, intravenous infusion of the anti-CD4 binding site bnAb, VRC01, prevents HIV-1 infection. These are the first test-of-concept studies to assess HIV-1 bnAb prevention efficacy in humans. The AMP trials are two parallel phase 2b HIV-1 prevention efficacy trials conducted in two cohorts: 2700 HIV-uninfected men and transgender persons who have sex with men in the United States, Peru, Brazil, and Switzerland; and 1500 HIV-uninfected sexually active women in seven countries in sub-Saharan Africa. Participants are randomized 1:1:1 to receive an intravenous infusion of 10 mg/kg VRC01, 30 mg/kg VRC01, or a control preparation every 8 weeks for a total of 10 infusions. Each trial is designed (1) to assess overall prevention efficacy (PE) pooled over the two VRC01 dose groups vs. control and (2) to assess VRC01 dose and laboratory markers as correlates of protection (CoPs) against overall and genotype- and phenotype-specific infection. Each AMP trial is designed to have 90% power to detect PE > 0% if PE is ≥ 60%. The AMP trials are also designed to identify VRC01 properties (i.e., concentration and effector functions) that correlate with protection and to provide insight into mechanistic CoPs. CoPs are assessed using data from breakthrough HIV-1 infections, including genetic sequences and sensitivities to VRC01-mediated neutralization and Fc effector functions. The AMP trials test whether VRC01 can prevent HIV-1 infection in two study populations. If affirmative, they will provide information for estimating the optimal dosage of VRC01 (or subsequent derivatives) and identify threshold levels of neutralization and Fc effector functions associated with high-level protection, setting a benchmark for future vaccine evaluation and constituting a bridge to other bnAb approaches for HIV-1 prevention.
Goulden, Peter A.; Bursac, Zoran; Hudson, Jonell; Purvis, Rachel S.; Yeary, Karen H. Kim; Aitaoto, Nia; Kohler, Peter O.
2016-01-01
This article illustrates how a collaborative research process can successfully engage an underserved minority community to address health disparities. Pacific Islanders, including the Marshallese, are one of the fastest growing US populations. They face significant health disparities, including extremely high rates of type 2 diabetes. This article describes the engagement process of designing patient-centered outcomes research with Marshallese stakeholders, highlighting the specific influences of their input on a randomized control trial to address diabetes. Over 18 months, an interdisciplinary research team used community-based participatory principles to conduct patient-engaged outcomes research that involved 31 stakeholders in all aspects of research design, from defining the research question to making decisions about budgets and staffing. This required academic researcher flexibility, but yielded a design linking scientific methodology with community wisdom. PMID:27325179
Cancer prevention clinical trials.
Nixon, D W
1994-01-01
Many kinds of cancer are preventable. Avoidance of tobacco would essentially eliminate lung cancer and most head and neck cancers as well. Other common cancers (breast, colon, prostate) are related to diet and therefore may also be preventable, at least in part. Abundant epidemiologic and laboratory data link specific nutrients including fat, fiber and vitamins to cancer so that appropriate manipulation of these constituents might reduce cancer risk. Determination of appropriate manipulations requires prospective clinical trials in humans. Approximately 40 such trials are in progress. Some have been completed with encouraging results. Future large scale trials will require designs that overcome the barriers of cost, large subject numbers and long study duration. The use of "intermediate markers" rather than cancer end points is a strategy that will help overcome these barriers.
Motor recovery after stroke: a systematic review.
Langhorne, Peter; Coupar, Fiona; Pollock, Alex
2009-08-01
Loss of functional movement is a common consequence of stroke for which a wide range of interventions has been developed. In this Review, we aimed to provide an overview of the available evidence on interventions for motor recovery after stroke through the evaluation of systematic reviews, supplemented by recent randomised controlled trials. Most trials were small and had some design limitations. Improvements in recovery of arm function were seen for constraint-induced movement therapy, electromyographic biofeedback, mental practice with motor imagery, and robotics. Improvements in transfer ability or balance were seen with repetitive task training, biofeedback, and training with a moving platform. Physical fitness training, high-intensity therapy (usually physiotherapy), and repetitive task training improved walking speed. Although the existing evidence is limited by poor trial designs, some treatments do show promise for improving motor recovery, particularly those that have focused on high-intensity and repetitive task-specific practice.
Halvarsson, Bodil
2018-01-01
Background The high physical load associated with running through uneven terrain contributes toorienteerers being exposed to high injury risk, where the majority of injuries are located in the lower extremities. Specific training programmes have been effective at reducing injury risk in sports. Yet no trial has been conducted in elite orienteering. The aim of this study is to investigate the effectiveness of a specific training programme in preventing lower extremity injury in adult elite orienteerers. Study design Randomised controlled trial (RCT). Methods Seventy-two Swedish elite orienteerers, aged 18–40 years, are allocated to an intervention or control group. The intervention group performs four specific exercises, with three difficult levels intensified every second week over the first 4 weeks, targeting strength, flexibility and coordination of the lower extremity. The exercises are completed four times a week (10 min per session) in conjunction with normal training over 14 weeks. Injury data are collected every second week using a valid injury questionnaire distributed by text messages over 14 weeks. The primary outcome is number of substantial injuries in the lower extremity. The secondary outcomes are incidence of ankle sprains and the average substantial injury prevalence across 14 weeks. Discussion Due to high injury risk and lack of injury prevention trials in orienteering, an RCT investigating the effect of a specific exercise programme in preventing lower extremity injury is warranted. The results of this trial will be beneficial to orienteerers, clubs and federations, and increase our understanding on how lower extremity injuries can be prevented in a physically challenging sport. Trial registration number NCT03408925. PMID:29707231
Brown, Sarah; Smith, Isabelle L; Brown, Julia M; Hulme, Claire; McGinnis, Elizabeth; Stubbs, Nikki; Nelson, E Andrea; Muir, Delia; Rutherford, Claudia; Walker, Kay; Henderson, Valerie; Wilson, Lyn; Gilberts, Rachael; Collier, Howard; Fernandez, Catherine; Hartley, Suzanne; Bhogal, Moninder; Coleman, Susanne; Nixon, Jane E
2016-12-20
Pressure ulcers represent a major burden to patients, carers and the healthcare system, affecting approximately 1 in 17 hospital and 1 in 20 community patients. They impact greatly on an individual's functional status and health-related quality of life. The mainstay of pressure ulcer prevention practice is the provision of pressure redistribution support surfaces and patient repositioning. The aim of the PRESSURE 2 study is to compare the two main mattress types utilised within the NHS: high-specification foam and alternating pressure mattresses, in the prevention of pressure ulcers. PRESSURE 2 is a multicentre, open-label, randomised, double triangular, group sequential, parallel group trial. A maximum of 2954 'high-risk' patients with evidence of acute illness will be randomised on a 1:1 basis to receive either a high-specification foam mattress or alternating-pressure mattress in conjunction with an electric profiling bed frame. The primary objective of the trial is to compare mattresses in terms of the time to developing a new Category 2 or above pressure ulcer by 30 days post end of treatment phase. Secondary endpoints include time to developing new Category 1 and 3 or above pressure ulcers, time to healing of pre-existing Category 2 pressure ulcers, health-related quality of life, cost-effectiveness, incidence of mattress change and safety. Validation objectives are to determine the responsiveness of the Pressure Ulcer Quality of Life-Prevention instrument and the feasibility of having a blinded endpoint assessment using photography. The trial will have a maximum of three planned analyses with unequally spaced reviews at event-driven coherent cut-points. The futility boundaries are constructed as non-binding to allow a decision for stopping early to be overruled by the Data Monitoring and Ethics Committee. The double triangular, group sequential design of the PRESSURE 2 trial will provide an efficient design through the possibility of early stopping for demonstrating either superiority, inferiority of mattresses or futility of the trial. The trial optimises the potential for producing robust clinical evidence on the effectiveness of two commonly used mattresses in clinical practice earlier than in a conventional design. ISRCTN01151335 . Registered on 14 May 2013. Protocol version: 5.0, dated 25 September 2015 Trial sponsor: Clare Skinner, Faculty Head of Research Support, University of Leeds, Leeds, LS2 9JT; 0113 343 4897; C.E.Skinner@leeds.ac.uk.
Tenaerts, P; Madre, L; Landray, M
2018-02-01
The Clinical Trials Transformation Initiative reflects on 10 years of working to improve the quality and efficiency of clinical trials. This article highlights many of the Clinical Trials Transformation Initiative's accomplishments and offers examples of the impact that the Clinical Trials Transformation Initiative has had on the clinical trials enterprise. After conducting more than 25 projects and issuing recommendations for specific strategies to improve the design and execution of clinical trials, some common themes and lessons learned have emerged. Lessons include the importance of engaging many stakeholders, advanced planning to address critical issues, discontinuation of non-value added practices, and new opportunities presented by technology. Through its work, the Clinical Trials Transformation Initiative has also derived some operational best practices for conducting collaborative, multi-stakeholder projects covering project selection, project team dynamics and execution, and multi-stakeholder meetings and team discussions. Through these initiatives, the Clinical Trials Transformation Initiative has helped move the needle toward needed change in the clinical trials enterprise that has directly impacted stakeholders and patients alike.
Using meta-analysis to inform the design of subsequent studies of diagnostic test accuracy.
Hinchliffe, Sally R; Crowther, Michael J; Phillips, Robert S; Sutton, Alex J
2013-06-01
An individual diagnostic accuracy study rarely provides enough information to make conclusive recommendations about the accuracy of a diagnostic test; particularly when the study is small. Meta-analysis methods provide a way of combining information from multiple studies, reducing uncertainty in the result and hopefully providing substantial evidence to underpin reliable clinical decision-making. Very few investigators consider any sample size calculations when designing a new diagnostic accuracy study. However, it is important to consider the number of subjects in a new study in order to achieve a precise measure of accuracy. Sutton et al. have suggested previously that when designing a new therapeutic trial, it could be more beneficial to consider the power of the updated meta-analysis including the new trial rather than of the new trial itself. The methodology involves simulating new studies for a range of sample sizes and estimating the power of the updated meta-analysis with each new study added. Plotting the power values against the range of sample sizes allows the clinician to make an informed decision about the sample size of a new trial. This paper extends this approach from the trial setting and applies it to diagnostic accuracy studies. Several meta-analytic models are considered including bivariate random effects meta-analysis that models the correlation between sensitivity and specificity. Copyright © 2012 John Wiley & Sons, Ltd. Copyright © 2012 John Wiley & Sons, Ltd.
What can qualitative research do for randomised controlled trials? A systematic mapping review
O'Cathain, A; Thomas, K J; Drabble, S J; Rudolph, A; Hewison, J
2013-01-01
Objective To develop an empirically based framework of the aspects of randomised controlled trials addressed by qualitative research. Design Systematic mapping review of qualitative research undertaken with randomised controlled trials and published in peer-reviewed journals. Data sources MEDLINE, PreMEDLINE, EMBASE, the Cochrane Library, Health Technology Assessment, PsycINFO, CINAHL, British Nursing Index, Social Sciences Citation Index and ASSIA. Eligibility criteria Articles reporting qualitative research undertaken with trials published between 2008 and September 2010; health research, reported in English. Results 296 articles met the inclusion criteria. Articles focused on 22 aspects of the trial within five broad categories. Some articles focused on more than one aspect of the trial, totalling 356 examples. The qualitative research focused on the intervention being trialled (71%, 254/356); the design, process and conduct of the trial (15%, 54/356); the outcomes of the trial (1%, 5/356); the measures used in the trial (3%, 10/356); and the target condition for the trial (9%, 33/356). A minority of the qualitative research was undertaken at the pretrial stage (28%, 82/296). The value of the qualitative research to the trial itself was not always made explicit within the articles. The potential value included optimising the intervention and trial conduct, facilitating interpretation of the trial findings, helping trialists to be sensitive to the human beings involved in trials, and saving money by steering researchers towards interventions more likely to be effective in future trials. Conclusions A large amount of qualitative research undertaken with specific trials has been published, addressing a wide range of aspects of trials, with the potential to improve the endeavour of generating evidence of effectiveness of health interventions. Researchers can increase the impact of this work on trials by undertaking more of it at the pretrial stage and being explicit within their articles about the learning for trials and evidence-based practice. PMID:23794542
Eldredge, Jonathan D
2003-06-01
to describe the essential components of the Randomised Controlled Trial (RCT) and its major variations; to describe less conventional applications of the RCT design found in the health sciences literature with potential relevance to health sciences librarianship; to discuss the limited number of RCTs within health sciences librarianship. narrative review supported to a limited extent with PubMed and Library Literature database searches consistent with specific search parameters. In addition, more systematic methods, including handsearching of specific journals, to identify health sciences librarianship RCTs. While many RCTs within the health sciences follow more conventional patterns, some RCTs assume certain unique features. Selected examples illustrate the adaptations of this experimental design to answering questions of possible relevance to health sciences librarians. The author offers several strategies for controlling bias in library and informatics applications of the RCT and acknowledges the potential of the electronic era in providing many opportunities to utilize the blinding aspects of RCTs. RCTs within health sciences librarianship inhabit a limited number of subject domains such as education. This limited scope offers both advantages and disadvantages for making Evidence-Based Librarianship (EBL) a reality. The RCT design offers the potential to answer far more EBL questions than have been addressed by the design to date. Librarians need only extend their horizons through use of the versatile RCT design into new subject domains to facilitate making EBL a reality.
ERIC Educational Resources Information Center
Storkel, Holly L.; Voelmle, Krista; Fierro, Veronica; Flake, Kelsey; Fleming, Kandace K.; Romine, Rebecca Swinburne
2017-01-01
Purpose: This study sought to identify an adequate intensity of interactive book reading for new word learning by children with specific language impairment (SLI) and to examine variability in treatment response. Method: An escalation design adapted from nontoxic drug trials (Hunsberger, Rubinstein, Dancey, & Korn, 2005) was used in this Phase…
2013-01-01
Background Chronic low back pain is an expensive and difficult condition to treat. One of the interventions widely used by physiotherapists in the treatment of chronic non-specific low back pain is exercise therapy based upon the Pilates principles. Pilates exercises can be performed with or without specific equipment. These two types of Pilates exercises have never been compared on a high-quality randomised controlled trial. Methods/design This randomised controlled trial with a blinded assessor will evaluate eighty six patients of both genders with chronic low back pain, aged between 18 and 60 years, from one Brazilian private physiotherapy clinic. The patients will be randomly allocated into two groups: Mat Group will perform the exercises on the ground while the Equipment-based Group will perform the Pilates method exercises on the following equipment: Cadillac, Reformer, Ladder Barrel, and Step Chair. The general and specific disability of the patient, kinesiophobia, pain intensity and global perceived effect will be evaluated by a blinded assessor before randomisation and at six weeks and six months after randomisation. In addition, the expectation of the participants and their confidence with the treatment will be evaluated before randomisation and after the first treatment session, respectively. Discussion This will be the first study aiming to compare the effectiveness of Mat and Equipment-based Pilates exercises in patients with chronic non-specific low back pain. The results may help health-care professionals in clinical decision-making and could potentially reduce the treatment costs of this condition. Trial registration Brazilian Registry of Clinical Trials RBR-7tyg5j PMID:23298183
Donovan, Jenny L; Young, Grace J; Walsh, Eleanor I; Metcalfe, Chris; Lane, J Athene; Martin, Richard M; Tazewell, Marta K; Davis, Michael; Peters, Tim J; Turner, Emma L; Mills, Nicola; Khazragui, Hanan; Khera, Tarnjit K; Neal, David E; Hamdy, Freddie C
2018-04-01
Randomized controlled trials (RCTs) deliver robust internally valid evidence but generalizability is often neglected. Design features built into the Prostate testing for cancer and Treatment (ProtecT) RCT of treatments for localized prostate cancer (PCa) provided insights into its generalizability. Population-based cluster randomization created a prospective study of prostate-specific antigen (PSA) testing and a comprehensive-cohort study including groups choosing treatment or excluded from the RCT, as well as those randomized. Baseline information assessed selection and response during RCT conduct. The prospective study (82,430 PSA-tested men) represented healthy men likely to respond to a screening invitation. The extended comprehensive cohort comprised 1,643 randomized, 997 choosing treatment, and 557 excluded with advanced cancer/comorbidities. Men choosing treatment were very similar to randomized men except for having more professional/managerial occupations. Excluded men were similar to the randomized socio-demographically but different clinically, representing less healthy men with more advanced PCa. The design features of the ProtecT RCT provided data to assess the representativeness of the prospective cohort and generalizability of the findings of the RCT. Greater attention to collecting data at the design stage of pragmatic trials would better support later judgments by clinicians/policy-makers about the generalizability of RCT findings in clinical practice. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.
Noninferiority trial designs for odds ratios and risk differences.
Hilton, Joan F
2010-04-30
This study presents constrained maximum likelihood derivations of the design parameters of noninferiority trials for binary outcomes with the margin defined on the odds ratio (ψ) or risk-difference (δ) scale. The derivations show that, for trials in which the group-specific response rates are equal under the point-alternative hypothesis, the common response rate, π(N), is a fixed design parameter whose value lies between the control and experimental rates hypothesized at the point-null, {π(C), π(E)}. We show that setting π(N) equal to the value of π(C) that holds under H(0) underestimates the overall sample size requirement. Given {π(C), ψ} or {π(C), δ} and the type I and II error rates, or algorithm finds clinically meaningful design values of π(N), and the corresponding minimum asymptotic sample size, N=n(E)+n(C), and optimal allocation ratio, γ=n(E)/n(C). We find that optimal allocations are increasingly imbalanced as ψ increases, with γ(ψ)<1 and γ(δ)≈1/γ(ψ), and that ranges of allocation ratios map to the minimum sample size. The latter characteristic allows trialists to consider trade-offs between optimal allocation at a smaller N and a preferred allocation at a larger N. For designs with relatively large margins (e.g. ψ>2.5), trial results that are presented on both scales will differ in power, with more power lost if the study is designed on the risk-difference scale and reported on the odds ratio scale than vice versa. 2010 John Wiley & Sons, Ltd.
Accounting for interim safety monitoring of an adverse event upon termination of a clinical trial.
Dallas, Michael J
2008-01-01
Upon termination of a clinical trial that uses interim evaluations to determine whether the trial can be stopped, a proper statistical analysis must account for the interim evaluations. For example, in a group-sequential design where the efficacy of a treatment regimen is evaluated at interim stages, and the opportunity to stop the trial based on positive efficacy findings exists, the terminal p-value, point estimate, and confidence limits of the outcome of interest must be adjusted to eliminate bias. While it is standard practice to adjust terminal statistical analyses due to opportunities to stop for "positive" findings, adjusting due to opportunities to stop for "negative" findings is also important. Stopping rules for negative findings are particularly useful when monitoring a specific rare serious adverse event in trials designed to show safety with respect to the event. In these settings, establishing conservative stopping rules are appropriate, and therefore accounting for the interim monitoring can have a substantial effect on the final results. Here I present a method to account for interim safety monitoring and illustrate its usefulness. The method is demonstrated to have advantages over methodology that does not account for interim monitoring.
Dominguez-Rodriguez, Alberto; Burillo-Putze, Guillermo; Garcia-Saiz, Maria Del Mar; Aldea-Perona, Ana; Harmand, Magali González-Colaço; Mirò, Oscar; Abreu-Gonzalez, Pedro
2017-04-01
Morphine has been used for several decades in cases of acute pulmonary edema (APE) due to the anxiolytic and vasodilatory properties of the drug. The non-specific depression of the central nervous system is probably the most significant factor for the changes in hemodynamics in APE. Retrospective studies have shown both negative and neutral effects in patients with APE and therefore some authors have suggested benzodiazepines as an alternative treatment. The use of intravenous morphine in the treatment of APE remains controversial. The MIdazolan versus MOrphine in APE trial (MIMO) is a multicenter, prospective, open-label, randomized study designed to evaluate the efficacy and safety of morphine in patients with APE. The MIMO trial will evaluate as a primary endpoint whether intravenous morphine administration improves clinical outcomes defined as in-hospital mortality. Secondary endpoint evaluation will be mechanical ventilation, cardiopulmonary resuscitation, intensive care unit admission rate, intensive care unit length of stay, and hospitalization length. In the emergency department, morphine is still used for APE in spite of poor scientific background data. The data from the MIMO trial will establish the effect-and especially the risk-when using morphine for APE.
Li, Bin; Shin, Hyunjin; Gulbekyan, Georgy; Pustovalova, Olga; Nikolsky, Yuri; Hope, Andrew; Bessarabova, Marina; Schu, Matthew; Kolpakova-Hart, Elona; Merberg, David; Dorner, Andrew; Trepicchio, William L.
2015-01-01
Development of drug responsive biomarkers from pre-clinical data is a critical step in drug discovery, as it enables patient stratification in clinical trial design. Such translational biomarkers can be validated in early clinical trial phases and utilized as a patient inclusion parameter in later stage trials. Here we present a study on building accurate and selective drug sensitivity models for Erlotinib or Sorafenib from pre-clinical in vitro data, followed by validation of individual models on corresponding treatment arms from patient data generated in the BATTLE clinical trial. A Partial Least Squares Regression (PLSR) based modeling framework was designed and implemented, using a special splitting strategy and canonical pathways to capture robust information for model building. Erlotinib and Sorafenib predictive models could be used to identify a sub-group of patients that respond better to the corresponding treatment, and these models are specific to the corresponding drugs. The model derived signature genes reflect each drug’s known mechanism of action. Also, the models predict each drug’s potential cancer indications consistent with clinical trial results from a selection of globally normalized GEO expression datasets. PMID:26107615
Li, Bin; Shin, Hyunjin; Gulbekyan, Georgy; Pustovalova, Olga; Nikolsky, Yuri; Hope, Andrew; Bessarabova, Marina; Schu, Matthew; Kolpakova-Hart, Elona; Merberg, David; Dorner, Andrew; Trepicchio, William L
2015-01-01
Development of drug responsive biomarkers from pre-clinical data is a critical step in drug discovery, as it enables patient stratification in clinical trial design. Such translational biomarkers can be validated in early clinical trial phases and utilized as a patient inclusion parameter in later stage trials. Here we present a study on building accurate and selective drug sensitivity models for Erlotinib or Sorafenib from pre-clinical in vitro data, followed by validation of individual models on corresponding treatment arms from patient data generated in the BATTLE clinical trial. A Partial Least Squares Regression (PLSR) based modeling framework was designed and implemented, using a special splitting strategy and canonical pathways to capture robust information for model building. Erlotinib and Sorafenib predictive models could be used to identify a sub-group of patients that respond better to the corresponding treatment, and these models are specific to the corresponding drugs. The model derived signature genes reflect each drug's known mechanism of action. Also, the models predict each drug's potential cancer indications consistent with clinical trial results from a selection of globally normalized GEO expression datasets.
Proposed variations of the stepped-wedge design can be used to accommodate multiple interventions.
Lyons, Vivian H; Li, Lingyu; Hughes, James P; Rowhani-Rahbar, Ali
2017-06-01
Stepped-wedge design (SWD) cluster-randomized trials have traditionally been used for evaluating a single intervention. We aimed to explore design variants suitable for evaluating multiple interventions in an SWD trial. We identified four specific variants of the traditional SWD that would allow two interventions to be conducted within a single cluster-randomized trial: concurrent, replacement, supplementation, and factorial SWDs. These variants were chosen to flexibly accommodate study characteristics that limit a one-size-fits-all approach for multiple interventions. In the concurrent SWD, each cluster receives only one intervention, unlike the other variants. The replacement SWD supports two interventions that will not or cannot be used at the same time. The supplementation SWD is appropriate when the second intervention requires the presence of the first intervention, and the factorial SWD supports the evaluation of intervention interactions. The precision for estimating intervention effects varies across the four variants. Selection of the appropriate design variant should be driven by the research question while considering the trade-off between the number of steps, number of clusters, restrictions for concurrent implementation of the interventions, lingering effects of each intervention, and precision of the intervention effect estimates. Copyright © 2017 Elsevier Inc. All rights reserved.
Kyte, Derek G; Draper, Heather; Ives, Jonathan; Liles, Clive; Gheorghe, Adrian; Calvert, Melanie
2013-01-01
Patient reported outcomes (PROs) are increasingly assessed in clinical trials, and guidelines are available to inform the design and reporting of such trials. However, researchers involved in PRO data collection report that specific guidance on 'in-trial' activity (recruitment, data collection and data inputting) and the management of 'concerning' PRO data (i.e., data which raises concern for the well-being of the trial participant) appears to be lacking. The purpose of this review was to determine the extent and nature of published guidelines addressing these areas. Systematic review of 1,362 articles identified 18 eligible papers containing 'in-trial' guidelines. Two independent authors undertook a qualitative content analysis of the selected papers. Guidelines presented in each of the articles were coded according to an a priori defined coding frame, which demonstrated reliability (pooled Kappa 0.86-0.97), and validity (<2% residual category coding). The majority of guidelines present were concerned with 'pre-trial' activities (72%), for example, outcome measure selection and study design issues, or 'post-trial' activities (16%) such as data analysis, reporting and interpretation. 'In-trial' guidelines represented 9.2% of all guidance across the papers reviewed, with content primarily focused on compliance, quality control, proxy assessment and reporting of data collection. There were no guidelines surrounding the management of concerning PRO data. The findings highlight there are minimal in-trial guidelines in publication regarding PRO data collection and management in clinical trials. No guidance appears to exist for researchers involved with the handling of concerning PRO data. Guidelines are needed, which support researchers to manage all PRO data appropriately and which facilitate unbiased data collection.
2012-01-01
Background Randomized controlled trials (RCTs) may be discontinued because of apparent harm, benefit, or futility. Other RCTs are discontinued early because of insufficient recruitment. Trial discontinuation has ethical implications, because participants consent on the premise of contributing to new medical knowledge, Research Ethics Committees (RECs) spend considerable effort reviewing study protocols, and limited resources for conducting research are wasted. Currently, little is known regarding the frequency and characteristics of discontinued RCTs. Methods/Design Our aims are, first, to determine the prevalence of RCT discontinuation for specific reasons; second, to determine whether the risk of RCT discontinuation for specific reasons differs between investigator- and industry-initiated RCTs; third, to identify risk factors for RCT discontinuation due to insufficient recruitment; fourth, to determine at what stage RCTs are discontinued; and fifth, to examine the publication history of discontinued RCTs. We are currently assembling a multicenter cohort of RCTs based on protocols approved between 2000 and 2002/3 by 6 RECs in Switzerland, Germany, and Canada. We are extracting data on RCT characteristics and planned recruitment for all included protocols. Completion and publication status is determined using information from correspondence between investigators and RECs, publications identified through literature searches, or by contacting the investigators. We will use multivariable regression models to identify risk factors for trial discontinuation due to insufficient recruitment. We aim to include over 1000 RCTs of which an anticipated 150 will have been discontinued due to insufficient recruitment. Discussion Our study will provide insights into the prevalence and characteristics of RCTs that were discontinued. Effective recruitment strategies and the anticipation of problems are key issues in the planning and evaluation of trials by investigators, Clinical Trial Units, RECs and funding agencies. Identification and modification of barriers to successful study completion at an early stage could help to reduce the risk of trial discontinuation, save limited resources, and enable RCTs to better meet their ethical requirements. PMID:22928744
Considerations of sex and gender differences in preclinical and clinical trials.
Raz, Limor; Miller, Virginia M
2012-01-01
Women continue to be underrepresented in clinical trials, particularly in Phases I and II of experimental drug studies in spite of legislative guidelines in the USA, Canada, the European Union, Australia, and Japan requiring the inclusion of women in clinical trials. As such, women remain a vulnerable population subject to the adverse effects of pharmacological therapies. Thus, women experience higher rates of adverse drug reactions than do men and for women of reproductive age or who may be pregnant, therapeutic options may be limited. This chapter provides a brief history of inclusion of sex and gender as variables in clinical trials, summarizes governmental legislation for consideration of sex and gender in clinical trials and provides specific examples of drugs which have been withdrawn from the market because of side effects in women. Additional information related to sex and gender in preclinical testing, trial design, challenges to recruitment of women for clinical trials and statistical methods for analysis of data also is considered.
Prospective registration of clinical trials in India: strategies, achievements & challenges.
Tharyan, Prathap
2009-02-01
This paper traces the development of the Clinical Trial Registry-India (CTRI) against the backdrop of the inequities in healthcare and the limitations in the design, conduct, regulation, oversight and reporting of clinical trials in India. It describes the scope and goals of the CTRI, the data elements it seeks and the process of registering clinical trials. It reports progress in trial registration in India and discusses the challenges in ensuring that healthcare decisions are informed by all the evidence. A descriptive survey of developments in clinical trial registration in India from publications in the Indian medical literature supplemented by first hand knowledge of these developments and an evaluation of how well clinical trials registered in the CTRI up to 10 January, 2009 comply with the requirements of the CTRI and the World Health Organization's International Clinical Trial Registry (WHO ICTRP). Considerable inequities exist within the Indian health system. Deficiencies in healthcare provision and uneven regulation of, and access to, affordable healthcare co-exists with a large private health system of uneven quality. India is now a preferred destination for outsourced clinical trials but is plagued by poor ethical oversight of the many trial sites and scant information of their existence. The CTRI's vision of conforming to international requirements for transparency and accountability but also using trial registration as a means of improving trial design, conduct and reporting led to the selection of registry-specific dataset items in addition to those endorsed by the WHO ICTRP. Compliance with these requirements is good for the trials currently registered but these trials represent only a fraction of the trials in progress in India. Prospective trial registration is a reality in India. The challenges facing the CTRI include better engagement with key stakeholders to ensure increased prospective registration of clinical trials and utilization of existing legislative opportunities to complement these efforts. © 2009 Blackwell Publishing Asia Pty Ltd and Chinese Cochrane Center, West China Hospital of Sichuan University.
Proposed variations of the stepped-wedge design can be used to accommodate multiple interventions
Lyons, Vivian H; Li, Lingyu; Hughes, James P; Rowhani-Rahbar, Ali
2018-01-01
Objective Stepped wedge design (SWD) cluster randomized trials have traditionally been used for evaluating a single intervention. We aimed to explore design variants suitable for evaluating multiple interventions in a SWD trial. Study Design and Setting We identified four specific variants of the traditional SWD that would allow two interventions to be conducted within a single cluster randomized trial: Concurrent, Replacement, Supplementation and Factorial SWDs. These variants were chosen to flexibly accommodate study characteristics that limit a one-size-fits-all approach for multiple interventions. Results In the Concurrent SWD, each cluster receives only one intervention, unlike the other variants. The Replacement SWD supports two interventions that will not or cannot be employed at the same time. The Supplementation SWD is appropriate when the second intervention requires the presence of the first intervention, and the Factorial SWD supports the evaluation of intervention interactions. The precision for estimating intervention effects varies across the four variants. Conclusion Selection of the appropriate design variant should be driven by the research question while considering the trade-off between the number of steps, number of clusters, restrictions for concurrent implementation of the interventions, lingering effects of each intervention, and precision of the intervention effect estimates. PMID:28412466
Issues related to development of antiepileptogenic therapies.
Pitkänen, Asla; Nehlig, Astrid; Brooks-Kayal, Amy R; Dudek, F Edward; Friedman, Daniel; Galanopoulou, Aristea S; Jensen, Frances E; Kaminski, Rafal M; Kapur, Jaideep; Klitgaard, Henrik; Löscher, Wolfgang; Mody, Istvan; Schmidt, Dieter
2013-08-01
Several preclinical proof-of-concept studies have provided evidence for positive treatment effects on epileptogenesis. However, none of these hypothetical treatments has advanced to the clinic. The experience in other fields of neurology such as stroke, Alzheimer's disease, or amyotrophic lateral sclerosis has indicated several problems in the design of preclinical studies, which likely contribute to failures in translating the positive preclinical data to the clinic. The Working Group on "Issues related to development of antiepileptogenic therapies" of the International League Against Epilepsy (ILAE) and the American Epilepsy Society (AES) has considered the possible problems that arise when moving from proof-of-concept antiepileptogenesis (AEG) studies to preclinical AEG trials, and eventually to clinical AEG trials. This article summarizes the discussions and provides recommendations on how to design a preclinical AEG monotherapy trial in adult animals. We specifically address study design, animal and model selection, number of studies needed, issues related to administration of the treatment, outcome measures, statistics, and reporting. In addition, we give recommendations for future actions to advance the preclinical AEG testing. Wiley Periodicals, Inc. © 2013 International League Against Epilepsy.
Koek, Mayke BG; Buskens, Erik; Steegmans, Paul HA; van Weelden, Huib; Bruijnzeel-Koomen, Carla AFM; Sigurdsson, Vigfús
2006-01-01
Background Home ultraviolet B (UVB) treatment is a much-debated treatment, especially with regard to effectiveness, safety and side effects. However, it is increasingly being prescribed, especially in the Netherlands. Despite ongoing discussions, no randomised research has been performed, and only two studies actually compare two groups of patients. Thus, firm evidence to support or discourage the use of home UVB phototherapy has not yet been obtained. This is the goal of the present study, the PLUTO study (Dutch acronym for "national trial on home UVB phototherapy for psoriasis"). Methods We designed a pragmatic randomised single-blind multi-centre trial. This trial is designed to evaluate the impact of home UVB treatment versus UVB phototherapy in a hospital outpatient clinic as to effectiveness, quality of life and cost-effectiveness. In total 196 patients with psoriasis who were clinically eligible for UVB phototherapy were included. Normally 85% of the patients treated with UVB show a relevant clinical response. With a power of 80% and a 0.05 significance level it will be possible to detect a reduction in effectiveness of 15%. Effectiveness will be determined by calculating differences in the Psoriasis Area and Severity Index (PASI) and the Self Administered PASI (SAPASI) scores. Quality of life is measured using several validated generic questionnaires and a disease-specific questionnaire. Other outcome measures include costs, side effects, dosimetry, concomitant use of medication and patient satisfaction. Patients are followed throughout the therapy and for 12 months thereafter. The study is no longer recruiting patients, and is expected to report in 2006. Discussion In the field of home UVB phototherapy this trial is the first randomised parallel group study. As such, this trial addresses the weaknesses encountered in previous studies. The pragmatic design ensures that the results can be well generalised to the target population. Because, in addition to effectiveness, aspects such as quality of life and cost-effectiveness are also taken into consideration, this study will produce valuable evidence to either support or discourage prescription of home UVB phototherapy. Trial registration Current controlled trials/Nederlands Trial register: ISRCTN83025173. Clinicaltrials.gov: NCT00150930 PMID:16882343
Heo, Moonseong; Meissner, Paul; Litwin, Alain H; Arnsten, Julia H; McKee, M Diane; Karasz, Alison; McKinley, Paula; Rehm, Colin D; Chambers, Earle C; Yeh, Ming-Chin; Wylie-Rosett, Judith
2017-01-01
Comparative effectiveness research trials in real-world settings may require participants to choose between preferred intervention options. A randomized clinical trial with parallel experimental and control arms is straightforward and regarded as a gold standard design, but by design it forces and anticipates the participants to comply with a randomly assigned intervention regardless of their preference. Therefore, the randomized clinical trial may impose impractical limitations when planning comparative effectiveness research trials. To accommodate participants' preference if they are expressed, and to maintain randomization, we propose an alternative design that allows participants' preference after randomization, which we call a "preference option randomized design (PORD)". In contrast to other preference designs, which ask whether or not participants consent to the assigned intervention after randomization, the crucial feature of preference option randomized design is its unique informed consent process before randomization. Specifically, the preference option randomized design consent process informs participants that they can opt out and switch to the other intervention only if after randomization they actively express the desire to do so. Participants who do not independently express explicit alternate preference or assent to the randomly assigned intervention are considered to not have an alternate preference. In sum, preference option randomized design intends to maximize retention, minimize possibility of forced assignment for any participants, and to maintain randomization by allowing participants with no or equal preference to represent random assignments. This design scheme enables to define five effects that are interconnected with each other through common design parameters-comparative, preference, selection, intent-to-treat, and overall/as-treated-to collectively guide decision making between interventions. Statistical power functions for testing all these effects are derived, and simulations verified the validity of the power functions under normal and binomial distributions.
Costa, Matthew R; Pollara, Justin; Edwards, Regina Whitney; Seaman, Michael S; Gorny, Miroslaw K; Montefiori, David C; Liao, Hua-Xin; Ferrari, Guido; Lu, Shan; Wang, Shixia
2016-11-15
HIV-1 is able to elicit broadly potent neutralizing antibodies in a very small subset of individuals only after several years of infection, and therefore, vaccines that elicit these types of antibodies have been difficult to design. The RV144 trial showed that moderate protection is possible and that this protection may correlate with antibody-dependent cellular cytotoxicity (ADCC) activity. Our previous studies demonstrated that in an HIV vaccine phase I trial, the DP6-001 trial, a polyvalent Env DNA prime-protein boost formulation could elicit potent and broadly reactive, gp120-specific antibodies with positive neutralization activities. Here we report on the production and analysis of HIV-1 Env-specific human monoclonal antibodies (hMAbs) isolated from vaccinees in the DP6-001 trial. For this initial report, 13 hMAbs from four vaccinees in the DP6-001 trial showed broad binding to gp120 proteins of diverse subtypes both autologous and heterologous to vaccine immunogens. Equally cross-reactive Fc receptor-mediated functional activities, including ADCC and antibody-dependent cellular phagocytosis (ADCP) activities, were present with both immune sera and isolated MAbs, confirming the induction of nonneutralizing functional hMAbs by the DNA prime-protein boost vaccination. Elicitation of broadly reactive hMAbs by vaccination in healthy human volunteers confirms the value of the polyvalent formulation in this HIV vaccine design. The roles of Fc receptor-mediated protective antibody responses are gaining more attention due to their potential contribution to the low-level protection against HIV-1 infection that they provided in the RV144 trial. At the same time, information about hMabs from other human HIV vaccine studies is very limited. In the current study, both immune sera and monoclonal antibodies from vaccinated humans showed not only high-level ADCC and ADCP activities but also cross-subtype ADCC and ADCP activities when a polyvalent DNA prime-protein boost vaccine formulation was used. Copyright © 2016, American Society for Microbiology. All Rights Reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Fitzgerald, Peter; Laughter, Mark D; Martyn, Rose
The Cylinder Accountability and Tracking System (CATS) is a tool designed for use by the International Atomic Energy Agency (IAEA) to improve overall inspector efficiency through real-time unattended monitoring of cylinder movements, site specific rules-based event detection, and the capability to integrate many types of monitoring technologies. The system is based on the tracking of cylinder movements using (radio frequency) RF tags, and the collection of data, such as accountability weights, that can be associated with the cylinders. This presentation will cover the installation and evaluation of the CATS at the Global Nuclear Fuels (GNF) fuel fabrication facility in Wilmington,more » NC. This system was installed to evaluate its safeguards applicability, operational durability under operating conditions, and overall performance. An overview of the system design and elements specific to the GNF deployment will be presented along with lessons learned from the installation process and results from the field trial.« less
Optimizing the early phase development of new analgesics by human pain biomarkers.
Arendt-Nielsen, Lars; Hoeck, Hans Christian
2011-11-01
Human pain biomarkers are based on standardized acute activation of pain pathways/mechanisms and quantitative assessment of the evoked responses. This approach can be applied to healthy volunteers, to pain patients, and before and after pharmacological interventions to help understanding and profile the mode of action (proof-of-concept) of new and existing analgesic compounds. Standardized stimuli of different modalities can be applied to different tissues (multimodal and multi-tissue) for profiling analgesic compounds with respect to modulation of pain transduction, transmission, specific mechanisms and processing. This approach substantiates which specific compounds may work in particular clinical pain conditions. Human pain biomarkers can be translational and may bridge animal findings in clinical pain conditions, which in turn can provide new possibilities for designing more successful clinical trials. Biomarker based proof-of-concept drug studies in either volunteers or selected patient populations provide inexpensive, fast and reliable mechanism-based information about dose-efficacy relationships. This is important information in the early drug development phase and for designing large expensive clinical trials.
The future of recombinant growth factors in wound healing.
Robson, M C; Mustoe, T A; Hunt, T K
1998-08-01
For more than a decade, clinical trials have been conducted of the application of topical exogenous recombinant growth factors in attempts to accelerate the healing of chronic wounds. Although the results of some of these trials have been encouraging, overall the results have been somewhat discouraging. Much of the difficulty lies in the paucity of carefully controlled clinical trials of wound healing. Since wound healing is a complex process that can be influenced, both positively and negatively, by many factors, designing these trials has proved difficult. To date, only a single recombinant growth factor-recombinant human platelet-derived growth factor-BB (rhPDGF-BB)- has been approved by the US Food and Drug Administration; and that only for use in diabetic foot ulcers. It is unlikely, however, that a single growth factor will be able to resolve all issues of repair or strengthen all vulnerabilities of chronic wounds. Our expectation, therefore, is that growth factors, cytokines, and other biologic agents will be used more specifically in the future, for example, by targeting growth factor therapy at those specific components or processes that a given wound uses to heal.
Perrachione, Tyler K.; Lee, Jiyeon; Ha, Louisa Y. Y.; Wong, Patrick C. M.
2011-01-01
Studies evaluating phonological contrast learning typically investigate either the predictiveness of specific pretraining aptitude measures or the efficacy of different instructional paradigms. However, little research considers how these factors interact—whether different students learn better from different types of instruction—and what the psychological basis for any interaction might be. The present study demonstrates that successfully learning a foreign-language phonological contrast for pitch depends on an interaction between individual differences in perceptual abilities and the design of the training paradigm. Training from stimuli with high acoustic-phonetic variability is generally thought to improve learning; however, we found high-variability training enhanced learning only for individuals with strong perceptual abilities. Learners with weaker perceptual abilities were actually impaired by high-variability training relative to a low-variability condition. A second experiment assessing variations on the high-variability training design determined that the property of this learning environment most detrimental to perceptually weak learners is the amount of trial-by-trial variability. Learners’ perceptual limitations can thus override the benefits of high-variability training where trial-by-trial variability in other irrelevant acoustic-phonetic features obfuscates access to the target feature. These results demonstrate the importance of considering individual differences in pretraining aptitudes when evaluating the efficacy of any speech training paradigm. PMID:21786912
Schnurr, Paula P; Friedman, Matthew J; Engel, Charles C; Foa, Edna B; Shea, M Tracie; Resick, Patricia M; James, Kenneth E; Chow, Bruce K
2005-12-01
This article describes issues in the design of an ongoing multisite randomized clinical trial of psychotherapy for treating posttraumatic stress disorder (PTSD) in female veterans and active duty personnel. Research aimed at testing treatments for PTSD in women who have served in the military is especially important due to the high prevalence of PTSD in this population. VA Cooperative Study 494 was designed to enroll 384 participants across 12 sites. Participants are randomly assigned to receive 10 weekly sessions of individual psychotherapy: Prolonged Exposure, a specific cognitive-behavioral therapy protocol for PTSD, or present-centered therapy, a comparison treatment that addresses current interpersonal problems but avoids a trauma focus. PTSD is the primary outcome. Additional outcomes are comorbid problems such as depression and anxiety; psychosocial function and quality of life; physical health status; satisfaction with treatment; and service utilization. Follow-up assessments are conducted at the end of treatment and then 3 and 6 months after treatment. Both treatments are delivered according to a manual. Videotapes of therapy sessions are viewed by experts who provide feedback to therapists throughout the trial to ensure adherence to the treatment manual. Discussion includes issues encountered in multisite psychotherapy trials along with the rationale for our decisions about how we addressed these issues in CSP #494.
Globally optimal trial design for local decision making.
Eckermann, Simon; Willan, Andrew R
2009-02-01
Value of information methods allows decision makers to identify efficient trial design following a principle of maximizing the expected value to decision makers of information from potential trial designs relative to their expected cost. However, in health technology assessment (HTA) the restrictive assumption has been made that, prospectively, there is only expected value of sample information from research commissioned within jurisdiction. This paper extends the framework for optimal trial design and decision making within jurisdiction to allow for optimal trial design across jurisdictions. This is illustrated in identifying an optimal trial design for decision making across the US, the UK and Australia for early versus late external cephalic version for pregnant women presenting in the breech position. The expected net gain from locally optimal trial designs of US$0.72M is shown to increase to US$1.14M with a globally optimal trial design. In general, the proposed method of globally optimal trial design improves on optimal trial design within jurisdictions by: (i) reflecting the global value of non-rival information; (ii) allowing optimal allocation of trial sample across jurisdictions; (iii) avoiding market failure associated with free-rider effects, sub-optimal spreading of fixed costs and heterogeneity of trial information with multiple trials. Copyright (c) 2008 John Wiley & Sons, Ltd.
The Australasian Resuscitation in Sepsis Evaluation (ARISE) trial statistical analysis plan.
Delaney, Anthony P; Peake, Sandra L; Bellomo, Rinaldo; Cameron, Peter; Holdgate, Anna; Howe, Belinda; Higgins, Alisa; Presneill, Jeffrey; Webb, Steve
2013-09-01
The Australasian Resuscitation in Sepsis Evaluation (ARISE) study is an international, multicentre, randomised, controlled trial designed to evaluate the effectiveness of early goal-directed therapy compared with standard care for patients presenting to the emergency department with severe sepsis. In keeping with current practice, and considering aspects of trial design and reporting specific to non-pharmacological interventions, our plan outlines the principles and methods for analysing and reporting the trial results. The document is prepared before completion of recruitment into the ARISE study, without knowledge of the results of the interim analysis conducted by the data safety and monitoring committee and before completion of the two related international studies. Our statistical analysis plan was designed by the ARISE chief investigators, and reviewed and approved by the ARISE steering committee. We reviewed the data collected by the research team as specified in the study protocol and detailed in the study case report form. We describe information related to baseline characteristics, characteristics of delivery of the trial interventions, details of resuscitation, other related therapies and other relevant data with appropriate comparisons between groups. We define the primary, secondary and tertiary outcomes for the study, with description of the planned statistical analyses. We have developed a statistical analysis plan with a trial profile, mock-up tables and figures. We describe a plan for presenting baseline characteristics, microbiological and antibiotic therapy, details of the interventions, processes of care and concomitant therapies and adverse events. We describe the primary, secondary and tertiary outcomes with identification of subgroups to be analysed. We have developed a statistical analysis plan for the ARISE study, available in the public domain, before the completion of recruitment into the study. This will minimise analytical bias and conforms to current best practice in conducting clinical trials.
Singh, Harjeet; Figliola, Matthew J.; Dawson, Margaret J.; Olivares, Simon; Zhang, Ling; Yang, Ge; Maiti, Sourindra; Manuri, Pallavi; Senyukov, Vladimir; Jena, Bipulendu; Kebriaei, Partow; Champlin, Richard E.; Huls, Helen; Cooper, Laurence J. N.
2013-01-01
Adoptive transfer of T cells expressing a CD19-specific chimeric antigen receptor (CAR) is being evaluated in multiple clinical trials. Our current approach to adoptive immunotherapy is based on a second generation CAR (designated CD19RCD28) that signals through a CD28 and CD3-ζ endodomain. T cells are electroporated with DNA plasmids from the Sleeping Beauty (SB) transposon/transposase system to express this CAR. Stable integrants of genetically modified T cells can then be retrieved when co-cultured with designer artificial antigen presenting cells (aAPC) in the presence of interleukin (IL)-2 and 21. Here, we reveal how the platform technologies of SB-mediated transposition and CAR-dependent propagation on aAPC were adapted for human application. Indeed, we have initiated clinical trials in patients with high-risk B-lineage malignancies undergoing autologous and allogeneic hematopoietic stem-cell transplantation (HSCT). We describe the process to manufacture clinical grade CD19-specific T cells derived from healthy donors. Three validation runs were completed in compliance with current good manufacturing practice for Phase I/II trials demonstrating that by 28 days of co-culture on γ-irradiated aAPC ∼1010 T cells were produced of which >95% expressed CAR. These genetically modified and propagated T cells met all quality control testing and release criteria in support of infusion. PMID:23741305
Scheltens, Nienke M E; Kuyper, Ingrid S; Boellaard, Ronald; Barkhof, Frederik; Teunissen, Charlotte E; Broersen, Laus M; Lansbergen, Marieke M; van der Flier, Wiesje M; van Berckel, Bart N M; Scheltens, Philip
2016-11-01
Alzheimer's disease is associated with early synaptic loss. Specific nutrients are known to be rate limiting for synapse formation. Studies have shown that administering specific nutrients may improve memory function, possibly by increasing synapse formation. This Dutch study explores the Effect of a specific Nutritional Intervention on cerebral Glucose Metabolism in early Alzheimer's disease (NL-ENIGMA, Dutch Trial Register NTR4718, http://www.trialregister.nl/trialreg/admin/rctview.asp?TC=4718). The NL-ENIGMA study is designed to test whether the specific multinutrient combination Fortasyn Connect present in the medical food Souvenaid influences cerebral glucose metabolism as a marker for improved synapse function. This study is a double-blind, randomized controlled parallel-group single-center trial. Forty drug-naive patients with mild cognitive impairment or mild dementia with evidence of amyloid deposition are 1:1 randomized to receive either the multinutrient combination or placebo once daily. Main exploratory outcome parameters include absolute quantitative positron emission tomography with 18 F-fluorodeoxyglucose (including arterial sampling) and standard uptake value ratios normalized for the cerebellum or pons after 24 weeks. We expect the NL-ENIGMA study to provide further insight in the potential of this multinutrient combination to improve synapse function.
Mathe, Nonsikelelo; Johnson, Steven T; Wozniak, Lisa A; Majumdar, Sumit R; Johnson, Jeffrey A
2015-08-25
Randomized controlled trials are considered the "gold standard" for scientific rigor in the assessment of benefits and harms of interventions in healthcare. They may not always be feasible, however, when evaluating quality improvement interventions in real-world healthcare settings. Non-randomized controlled trials (NCTs) are designed to answer questions of effectiveness of interventions in routine clinical practice to inform a decision or process. The on-off NCT design is a relatively new design where participant allocation is by alternation. In alternation, eligible patients are allocated to the intervention "on" or control "off " groups in time series dependent sequential clusters. We used two quality improvement studies undertaken in a Canadian primary care setting to illustrate the features of the on-off design. We also explored the perceptions and experiences of healthcare providers tasked with implementing the on-off study design. The on-off design successfully allocated patients to intervention and control groups. Imbalances between baseline variables were attributed to chance, with no detectable biases. However, healthcare providers' perspectives and experiences with the design in practice reveal some conflict. Specifically, providers described the process of allocating patients to the off group as unethical and immoral, feeling it was in direct conflict with their professional principle of providing care for all. The degree of dissatisfaction seemed exacerbated by: 1) the patient population involved (e.g., patient population viewed as high-risk (e.g., depressed or suicidal)), 2) conducting assessments without taking action (e.g., administering the PHQ-9 and not acting on the results), and 3) the (non-blinded) allocation process. Alternation, as in the on-off design, is a credible form of allocation. The conflict reported by healthcare providers in implementing the design, while not unique to the on-off design, may be alleviated by greater emphasis on the purpose of the research and having research assistants allocate patients and collect data instead of the healthcare providers implementing the trial. In addition, consultation with front-line staff implementing the trials with an on-off design on appropriateness to the setting (e.g., alignment with professional values and the patient population served) may be beneficial. Health Eating and Active Living with Diabetes: ClinicalTrials.gov identifier: NCT00991380. Date registered: 7 October 2009. Controlled trial of a collaborative primary care team model for patients with diabetes and depression: Clintrials.gov Identifier: NCT01328639 Date registered: 30 March 2011.
Guetterman, Timothy C; Fetters, Michael D; Mawocha, Samkeliso; Legocki, Laurie J; Barsan, William G; Lewis, Roger J; Berry, Donald A; Meurer, William J
2017-01-01
Clinical trials are complicated, expensive, time-consuming, and frequently do not lead to discoveries that improve the health of patients with disease. Adaptive clinical trials have emerged as a methodology to provide more flexibility in design elements to better answer scientific questions regarding whether new treatments are efficacious. Limited observational data exist that describe the complex process of designing adaptive clinical trials. To address these issues, the Adaptive Designs Accelerating Promising Treatments Into Trials project developed six, tailored, flexible, adaptive, phase-III clinical trials for neurological emergencies, and investigators prospectively monitored and observed the processes. The objective of this work is to describe the adaptive design development process, the final design, and the current status of the adaptive trial designs that were developed. To observe and reflect upon the trial development process, we employed a rich, mixed methods evaluation that combined quantitative data from visual analog scale to assess attitudes about adaptive trials, along with in-depth qualitative data about the development process gathered from observations. The Adaptive Designs Accelerating Promising Treatments Into Trials team developed six adaptive clinical trial designs. Across the six designs, 53 attitude surveys were completed at baseline and after the trial planning process completed. Compared to baseline, the participants believed significantly more strongly that the adaptive designs would be accepted by National Institutes of Health review panels and non-researcher clinicians. In addition, after the trial planning process, the participants more strongly believed that the adaptive design would meet the scientific and medical goals of the studies. Introducing the adaptive design at early conceptualization proved critical to successful adoption and implementation of that trial. Involving key stakeholders from several scientific domains early in the process appears to be associated with improved attitudes towards adaptive designs over the life cycle of clinical trial development.
Spiegel, Marshall L; Goldman, Jonathan W; Wolf, Brian R; Nameth, Danielle J; Grogan, Tristan R; Lisberg, Aaron E; Wong, Deborah J L; Ledezma, Blanca A; Mendenhall, Melody A; Genshaft, Scott J; Gutierrez, Antonio J; Abtin, Fereidoun; Wallace, W Dean; Adame, Carlos R; McKenzie, Jordan R; Abarca, Phillip A; Li, Alice J; Strunck, Jennifer L; Famenini, Sina; Carroll, James M; Tucker, D Andrew; Sauer, Lauren M; Moghadam, Nima M; Elashoff, David A; Abaya, Christina D; Brennan, Meghan B; Garon, Edward B
2017-12-15
Clinical trials in lung cancer increasingly require patients to provide fresh tumor tissue as a prerequisite to enrollment. The effects of this requirement on enrollment rates, enrollment durations, and patient selection have not been fully elucidated. The authors retrospectively reviewed data generated by patients who consented to 1 or more interventional lung cancer clinical trials at the University of California-Los Angeles Jonsson Comprehensive Cancer Center between January 2013 and December 2014. Trials were considered to require a biopsy when enrollment was conditional on the procurement of tissue without intervening therapy between procurement and enrollment. In total, 311 patients underwent 368 screening incidents for 1 or more of 19 trials. Trials that required a new biopsy had a longer median screening duration (34 vs 14 days) than trials that did not require a biopsy (P < .001). Trials that required a biopsy had a greater screen failure rate (49.1% vs 26.5%; P < .001), which was largely driven by patients who did not undergo the required biopsy or lacked the required biomarker. Worsening performance status led to the majority of screen failures (56.5%) among biomarker-eligible patients. Although the scientific benefits of obtaining a new biopsy and requiring specific results for trial enrollment are clear, these requirements lead to a lengthening of the screening period, which, in some patients, is associated with clinical decline before enrollment. Implications for the interpretation of data from studies of this design should be explored. Cancer 2017;123:4800-7. © 2017 American Cancer Society. © 2017 American Cancer Society.
Methodology of Clinical Trials Aimed at Assessing Interventions for Cutaneous Leishmaniasis
Olliaro, Piero; Vaillant, Michel; Arana, Byron; Grogl, Max; Modabber, Farrokh; Magill, Alan; Lapujade, Olivier; Buffet, Pierre; Alvar, Jorge
2013-01-01
The current evidence-base for recommendations on the treatment of cutaneous leishmaniasis (CL) is generally weak. Systematic reviews have pointed to a general lack of standardization of methods for the conduct and analysis of clinical trials of CL, compounded with poor overall quality of several trials. For CL, there is a specific need for methodologies which can be applied generally, while allowing the flexibility needed to cover the diverse forms of the disease. This paper intends to provide clinical investigators with guidance for the design, conduct, analysis and report of clinical trials of treatments for CL, including the definition of measurable, reproducible and clinically-meaningful outcomes. Having unified criteria will help strengthen evidence, optimize investments, and enhance the capacity for high-quality trials. The limited resources available for CL have to be concentrated in clinical studies of excellence that meet international quality standards. PMID:23556016
Pandis, Nikolaos; Polychronopoulou, Argy; Eliades, Theodore
2011-12-01
Randomization is a key step in reducing selection bias during the treatment allocation phase in randomized clinical trials. The process of randomization follows specific steps, which include generation of the randomization list, allocation concealment, and implementation of randomization. The phenomenon in the dental and orthodontic literature of characterizing treatment allocation as random is frequent; however, often the randomization procedures followed are not appropriate. Randomization methods assign, at random, treatment to the trial arms without foreknowledge of allocation by either the participants or the investigators thus reducing selection bias. Randomization entails generation of random allocation, allocation concealment, and the actual methodology of implementing treatment allocation randomly and unpredictably. Most popular randomization methods include some form of restricted and/or stratified randomization. This article introduces the reasons, which make randomization an integral part of solid clinical trial methodology, and presents the main randomization schemes applicable to clinical trials in orthodontics.
How Have Cancer Clinical Trial Eligibility Criteria Evolved Over Time?
Yaman, Anil; Chakrabarti, Shreya; Sen, Anando; Weng, Chunhua
2016-01-01
Knowledge reuse of cancer trial designs may benefit from a temporal understanding of the evolution of the target populations of cancer studies over time. Therefore, we conducted a retrospective analysis of the trends of cancer trial eligibility criteria between 1999 and 2014. The yearly distributions of eligibility concepts for chemicals and drugs, procedures, observations, and medical conditions extracted from free-text eligibility criteria of 32,000 clinical trials for 89 cancer types were analyzed. We identified the concepts that trend upwards or downwards in all or selected cancer types, and the concepts that show anomalous trends for some cancers. Later, concept trends were studied in a disease-specific manner and illustrated for breast cancer. Criteria trends observed in this study are also validated and interpreted using evidence from the existing medical literature. This study contributes a method for concept trend analysis and original knowledge of the trends in cancer clinical trial eligibility criteria. PMID:27570681
Setchell, J; Gard, M; Jones, L; Watson, B M
2017-08-01
In this article, we propose a theory-driven approach to developing interventions for reducing weight stigma in physiotherapy and discuss the design and exploratory trial of such an intervention. Weight stigma has been identified in physiotherapists in empirical investigations. However, there has been little consideration of how this stigma might be addressed. We highlight Goffman's work on stigma that provides social and embodied understandings of stigma. Goffman's approach, however, is notably apolitical, ahistorical and lacks mechanisms for understanding power. We suggest that post-structuralist perspectives can provide insight into these areas. Drawing on these theories, we critically examine the literature on weight stigma reduction, finding that trials have largely been unsuccessful. We argue that this may be due to overly passive and simplistic intervention designs. As context-specific understandings are desirable, we examine the nature of physiotherapy to determine what might be relevant to (re)thinking weight in this profession. We then discuss the development of a multifactorial, active weight stigma intervention we trialed with eight physiotherapists. Supported by theory, the outcomes of the exploratory study suggest that physiotherapy-specific factors such as fostering professional reflexivity and improving understandings of stigma need to be incorporated into an active intervention that considers the complex determinants of weight stigma.
Luce, Bryan R; Connor, Jason T; Broglio, Kristine R; Mullins, C Daniel; Ishak, K Jack; Saunders, Elijah; Davis, Barry R
2016-09-20
Bayesian and adaptive clinical trial designs offer the potential for more efficient processes that result in lower sample sizes and shorter trial durations than traditional designs. To explore the use and potential benefits of Bayesian adaptive clinical trial designs in comparative effectiveness research. Virtual execution of ALLHAT (Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial) as if it had been done according to a Bayesian adaptive trial design. Comparative effectiveness trial of antihypertensive medications. Patient data sampled from the more than 42 000 patients enrolled in ALLHAT with publicly available data. Number of patients randomly assigned between groups, trial duration, observed numbers of events, and overall trial results and conclusions. The Bayesian adaptive approach and original design yielded similar overall trial conclusions. The Bayesian adaptive trial randomly assigned more patients to the better-performing group and would probably have ended slightly earlier. This virtual trial execution required limited resampling of ALLHAT patients for inclusion in RE-ADAPT (REsearch in ADAptive methods for Pragmatic Trials). Involvement of a data monitoring committee and other trial logistics were not considered. In a comparative effectiveness research trial, Bayesian adaptive trial designs are a feasible approach and potentially generate earlier results and allocate more patients to better-performing groups. National Heart, Lung, and Blood Institute.
Peters-Klimm, Frank; Müller-Tasch, Thomas; Schellberg, Dieter; Gensichen, Jochen; Muth, Christiane; Herzog, Wolfgang; Szecsenyi, Joachim
2007-01-01
Background Chronic congestive heart failure (CHF) is a complex disease with rising prevalence, compromised quality of life (QoL), unplanned hospital admissions, high mortality and therefore high burden of illness. The delivery of care for these patients has been criticized and new strategies addressing crucial domains of care have been shown to be effective on patients' health outcomes, although these trials were conducted in secondary care or in highly organised Health Maintenance Organisations. It remains unclear whether a comprehensive primary care-based case management for the treating general practitioner (GP) can improve patients' QoL. Methods/Design HICMan is a randomised controlled trial with patients as the unit of randomisation. Aim is to evaluate a structured, standardized and comprehensive complex intervention for patients with CHF in a 12-months follow-up trial. Patients from intervention group receive specific patient leaflets and documentation booklets as well as regular monitoring and screening by a prior trained practice nurse, who gives feedback to the GP upon urgency. Monitoring and screening address aspects of disease-specific self-management, (non)pharmacological adherence and psychosomatic and geriatric comorbidity. GPs are invited to provide a tailored structured counselling 4 times during the trial and receive an additional feedback on pharmacotherapy relevant to prognosis (data of baseline documentation). Patients from control group receive usual care by their GPs, who were introduced to guideline-oriented management and a tailored health counselling concept. Main outcome measurement for patients' QoL is the scale physical functioning of the SF-36 health questionnaire in a 12-month follow-up. Secondary outcomes are the disease specific QoL measured by the Kansas City Cardiomyopathy questionnaire (KCCQ), depression and anxiety disorders (PHQ-9, GAD-7), adherence (EHFScBS and SANA), quality of care measured by an adapted version of the Patient Chronic Illness Assessment of Care questionnaire (PACIC) and NT-proBNP. In addition, comprehensive clinical data are collected about health status, comorbidity, medication and health care utilisation. Discussion As the targeted patient group is mostly cared for and treated by GPs, a comprehensive primary care-based guideline implementation including somatic, psychosomatic and organisational aspects of the delivery of care (HICMAn) is a promising intervention applying proven strategies for optimal care. Trial registration Current Controlled Trials ISRCTN30822978. PMID:17716364
Practical characteristics of adaptive design in phase 2 and 3 clinical trials.
Sato, A; Shimura, M; Gosho, M
2018-04-01
Adaptive design methods are expected to be ethical, reflect real medical practice, increase the likelihood of research and development success and reduce the allocation of patients into ineffective treatment groups by the early termination of clinical trials. However, the comprehensive details regarding which types of clinical trials will include adaptive designs remain unclear. We examined the practical characteristics of adaptive design used in clinical trials. We conducted a literature search of adaptive design clinical trials published from 2012 to 2015 using PubMed, EMBASE, and the Cochrane Central Register of Controlled Trials, with common search terms related to adaptive design. We systematically assessed the types and characteristics of adaptive designs and disease areas employed in the adaptive design trials. Our survey identified 245 adaptive design clinical trials. The number of trials by the publication year increased from 2012 to 2013 and did not greatly change afterwards. The most frequently used adaptive design was group sequential design (n = 222, 90.6%), especially for neoplasm or cardiovascular disease trials. Among the other types of adaptive design, adaptive dose/treatment group selection (n = 21, 8.6%) and adaptive sample-size adjustment (n = 19, 7.8%) were frequently used. The adaptive randomization (n = 8, 3.3%) and adaptive seamless design (n = 6, 2.4%) were less frequent. Adaptive dose/treatment group selection and adaptive sample-size adjustment were frequently used (up to 23%) in "certain infectious and parasitic diseases," "diseases of nervous system," and "mental and behavioural disorders" in comparison with "neoplasms" (<6.6%). For "mental and behavioural disorders," adaptive randomization was used in two trials of eight trials in total (25%). Group sequential design and adaptive sample-size adjustment were used frequently in phase 3 trials or in trials where study phase was not specified, whereas the other types of adaptive designs were used more in phase 2 trials. Approximately 82% (202 of 245 trials) resulted in early termination at the interim analysis. Among the 202 trials, 132 (54% of 245 trials) had fewer randomized patients than initially planned. This result supports the motive to use adaptive design to make study durations shorter and include a smaller number of subjects. We found that adaptive designs have been applied to clinical trials in various therapeutic areas and interventions. The applications were frequently reported in neoplasm or cardiovascular clinical trials. The adaptive dose/treatment group selection and sample-size adjustment are increasingly common, and these adaptations generally follow the Food and Drug Administration's (FDA's) recommendations. © 2017 John Wiley & Sons Ltd.
Hill, Anne-Marie; Hill, Keith; Brauer, Sandra; Oliver, David; Hoffmann, Tammy; Beer, Christopher; McPhail, Steven; Haines, Terry P
2009-01-01
Background Accidental falls by older patients in hospital are one of the most commonly reported adverse events. Falls after discharge are also common. These falls have enormous physical, psychological and social consequences for older patients, including serious physical injury and reduced quality of life, and are also a source of substantial cost to health systems worldwide. There have been a limited number of randomised controlled trials, mainly using multifactorial interventions, aiming to prevent older people falling whilst inpatients. Trials to date have produced conflicting results and recent meta-analyses highlight that there is still insufficient evidence to clearly identify which interventions may reduce the rate of falls, and falls related injuries, in this population. Methods and design A prospective randomised controlled trial (n = 1206) is being conducted at two hospitals in Australia. Patients are eligible to be included in the trial if they are over 60 years of age and they, or their family or guardian, give written consent. Participants are randomised into three groups. The control group continues to receive usual care. Both intervention groups receive a specifically designed patient education intervention on minimising falls in addition to usual care. The education is delivered by Digital Video Disc (DVD) and written workbook and aims to promote falls prevention activities by participants. One of the intervention groups also receives follow up education training visits by a health professional. Blinded assessors conduct baseline and discharge assessments and follow up participants for 6 months after discharge. The primary outcome measure is falls by participants in hospital. Secondary outcome measures include falls at home after discharge, knowledge of falls prevention strategies and motivation to engage in falls prevention activities after discharge. All analyses will be based on intention to treat principle. Discussion This trial will examine the effect of a single intervention (specifically designed patient education) on rates of falls in older patients in hospital and after discharge. The results will provide robust recommendations for clinicians and researchers about the role of patient education in this population. The study has the potential to identify a new intervention that may reduce rates of falls in older hospital patients and could be readily duplicated and applied in a wide range of clinical settings. Trial Registration ACTRN12608000015347 PMID:19393046
2012-01-01
Background The prevalence of amphetamine-type stimulant use is greater than that of opioids and cocaine combined. Currently, there are no approved pharmacotherapy treatments for amphetamine-type stimulant problems, but some face-to-face psychotherapies are of demonstrated effectiveness. However, most treatment services focus on alcohol or opioid disorders, have limited reach and may not appeal to users of amphetamine-type stimulants. Internet interventions have proven to be effective for some substance use problems but none has specifically targeted users of amphetamine-type stimulants. Design/method The study will use a randomized controlled trial design to evaluate the effect of an internet intervention for amphetamine-type stimulant problems compared with a waitlist control group. The primary outcome will be assessed as amphetamine-type stimulant use (baseline, 3 and 6 months). Other outcomes measures will include ‘readiness to change’, quality of life, psychological distress (K-10 score), days out of role, poly-drug use, help-seeking intention and help-seeking behavior. The intervention consists of three modules requiring an estimated total completion time of 90 minutes. The content of the modules was adapted from face-to-face clinical techniques based on cognitive behavior therapy and motivation enhancement. The target sample is 160 men and women aged 18 and over who have used amphetamine-type stimulants in the last 3 months. Discussion To our knowledge this will be the first randomized controlled trial of an internet intervention specifically developed for users of amphetamine-type stimulants. If successful, the intervention will offer greater reach than conventional therapies and may engage clients who do not generally seek treatment from existing service providers. Trial registration Australian and New Zealand Clinical Trials Registry (www.anzctr.org.au/) ACTRN12611000947909 PMID:22731926
Özlek, Bülent; Özlek, Eda; Çelik, Oğuzhan; Çil, Cem; Doğan, Volkan; Tekinalp, Mehmet; Zencirkıran Ağuş, Hicaz; Kahraman, Serkan; Ösken, Altuğ; Rencüzoğulları, İbrahim; Tanık, Veysel Ozan; Bekar, Lütfü; Çakır, Mustafa Ozan; Kaya, Bedri Caner; Tibilli, Hakan; Çelik, Yunus; Başaran, Özcan; Mert, Kadir Uğur; Sevinç, Samet; Demirci, Erkan; Dondurmacı, Engin; Biteker, Murat
2018-05-01
Although almost half of chronic heart failure (HF) patients have mid-range (HFmrEF) and preserved left-ventricular ejection fraction (HFpEF), no studies have been carried out with these patients in our country. This study aims to determine the demographic characteristics and current status of the clinical background of HFmrEF and HFpEF patients in a multicenter trial. A comPrehensive, ObservationaL registry of heart faiLure with mid range and preserved ejectiON fraction (APOLLON) trial will be an observational, multicenter, and noninterventional study conducted in Turkey. The study population will include 1065 patients from 12 sites in Turkey. All data will be collected at one point in time and the current clinical practice will be evaluated (ClinicalTrials.gov number NCT03026114). We will enroll all consecutive patients admitted to the cardiology clinics who were at least 18 years of age and had New York Heart Association class II, III, or IV HF, elevated brain natriuretic peptide levels within the last 30 days, and an left ventricular ejection fraction (LVEF) of at least 40%. Patients fulfilling the exclusion criteria will not be included in the study. Patients will be stratified into two categories according to LVEF: mid-range EF (HFmrEF, LVEF 40%-49%) and preserved EF (HFpEF, LVEF ≥50%). Regional quota sampling will be performed to ensure that the sample was representative of the Turkish population. Demographic, lifestyle, medical, and therapeutic data will be collected by this specific survey. The APOLLON trial will be the largest and most comprehensive study in Turkey evaluating HF patients with a LVEF ≥40% and will also be the first study to specifically analyze the recently designated HFmrEF category.
2010-01-01
Background Systematic reviews have shown that exercise therapy and spinal manipulation are both more effective for low back pain (LBP) than no treatment at all. However, the effects are at best modest. To enhance the clinical outcomes, recommendations are to improve the patient selection process, and to identify relevant subgroups to guide clinical decision-making. One of the systems that has potentials to improve clinical decision-making is a treatment-based classification system that is intended to identify those patients who are most likely to respond to direction-specific exercises, manipulation, or stabilisation exercises. Methods/Design The primary aim of this randomised controlled trial will be to assess the effectiveness of a classification-based system. A sample of 150 patients with subacute and chronic LBP who attend a private physical therapy clinic for treatment will be recruited. At baseline, all participants will undergo a standard evaluation by trained research physical therapists and will be classified into one of the following subgroups: direction-specific exercises, manipulation, or stabilisation. The patient will not be informed about the results of the examination. Patients will be randomly assigned to classification-based treatment or usual care according to the Dutch LBP guidelines, and will complete questionnaires at baseline, and 8, 26, and 52 weeks after the start of the treatment. The primary outcomes will be general perceived recovery, functional status, and pain intensity. Alongside this trial, an economic evaluation of cost-effectiveness and cost-utility will be conducted from a societal perspective. Discussion The present study will contribute to our knowledge about the effectiveness and cost-effectiveness of classification-based treatment in patients with LBP. Trial registration Trial registration number: NTR1176 PMID:20346133
Mertens, Bart J. A.; Jacobs, Wilco C. H.; Brand, Ronald; Peul, Wilco C.
2014-01-01
We consider a re-analysis of the wait-and-see (control) arm of a recent clinical trial on sciatica. While the original randomised trial was designed to evaluate the public policy effect of a conservative wait-and-see approach versus early surgery, we investigate the impact of surgery at the individual patient level in a re-analysis of the wait-and-see group data. Both marginal structural model re-weighted estimates as well as propensity score adjusted analyses are presented. Results indicate that patients with high propensity to receive surgery may have beneficial effects at 2 years from delayed disc surgery. PMID:25353633
Tapp, Alan; Pressley, Ashley; Baugh, Mike; White, Paul
2013-09-01
Young men from poorer backgrounds are associated with high road traffic collision levels. However, solving this problem has proven very difficult. Hence this paper summarises the findings of a UK government funded two-year trial of a cross-discipline intervention to reduce aggressive driving amongst this group. The intervention reported on here departed from traditional approaches such as fear appeals, stand-alone educational approaches, or punitive measures. Instead, the discipline of social marketing was used to provide overarching direction and structure for the trial, with a key focus on motivation and engagement. The project rested on a strong education and training platform and included a bespoke coaching programme, incentives, and an in-vehicle measurement and feedback device. The project had three development phases leading to the final trial. First, a literature and case study review identified possible design strategies. Second, these strategies were explored using primary research in the form of a qualitative inquiry. Third, a pre-trial design phase sought to introduce key components of the intervention to the trial cohort, retaining some flexibility before committing to the final design. Young males with a history of challenging behaviour (e.g. criminal records, driving convictions) from an economically deprived area within a UK city were recruited. Of 42 recruits, 23 successfully completed the trial. Behaviour changes were measured pre-, during and post-trial through a combination of driver performance data measured by in-vehicle data recorders (IVDRs), assessments of driving undertaken by trained observers, and self-assessment surveys and interviews with trial participants. Results indicate a significant average improvement in driving skills amongst participants who completed the trial. Given the difficulty in engaging and changing behaviour of this specific group, this is regarded as a significant finding. In summary the study provides an indication of proof of concept for the intervention in improving driving skills. However the limited sample size and lack of control group mean that further work will be required to validate these findings. It is recommended that a feasibility study with higher cohort volumes is undertaken, before attempting a full scale trial. Copyright © 2013 Elsevier Ltd. All rights reserved.
Sun, Yanqing; Qi, Li; Yang, Guangren; Gilbert, Peter B
2018-05-01
This article develops hypothesis testing procedures for the stratified mark-specific proportional hazards model with missing covariates where the baseline functions may vary with strata. The mark-specific proportional hazards model has been studied to evaluate mark-specific relative risks where the mark is the genetic distance of an infecting HIV sequence to an HIV sequence represented inside the vaccine. This research is motivated by analyzing the RV144 phase 3 HIV vaccine efficacy trial, to understand associations of immune response biomarkers on the mark-specific hazard of HIV infection, where the biomarkers are sampled via a two-phase sampling nested case-control design. We test whether the mark-specific relative risks are unity and how they change with the mark. The developed procedures enable assessment of whether risk of HIV infection with HIV variants close or far from the vaccine sequence are modified by immune responses induced by the HIV vaccine; this question is interesting because vaccine protection occurs through immune responses directed at specific HIV sequences. The test statistics are constructed based on augmented inverse probability weighted complete-case estimators. The asymptotic properties and finite-sample performances of the testing procedures are investigated, demonstrating double-robustness and effectiveness of the predictive auxiliaries to recover efficiency. The finite-sample performance of the proposed tests are examined through a comprehensive simulation study. The methods are applied to the RV144 trial. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Adaptive design clinical trials: a review of the literature and ClinicalTrials.gov
Bothwell, Laura E; Avorn, Jerry; Khan, Nazleen F; Kesselheim, Aaron S
2018-01-01
Objectives This review investigates characteristics of implemented adaptive design clinical trials and provides examples of regulatory experience with such trials. Design Review of adaptive design clinical trials in EMBASE, PubMed, Cochrane Registry of Controlled Clinical Trials, Web of Science and ClinicalTrials.gov. Phase I and seamless Phase I/II trials were excluded. Variables extracted from trials included basic study characteristics, adaptive design features, size and use of independent data monitoring committees (DMCs) and blinded interim analyses. We also examined use of the adaptive trials in new drug submissions to the Food and Drug Administration (FDA) and European Medicines Agency (EMA) and recorded regulators’ experiences with adaptive designs. Results 142 studies met inclusion criteria. There has been a recent growth in publicly reported use of adaptive designs among researchers around the world. The most frequently appearing types of adaptations were seamless Phase II/III (57%), group sequential (21%), biomarker adaptive (20%), and adaptive dose-finding designs (16%). About one-third (32%) of trials reported an independent DMC, while 6% reported blinded interim analysis. We found that 9% of adaptive trials were used for FDA product approval consideration, and 12% were used for EMA product approval consideration. International regulators had mixed experiences with adaptive trials. Many product applications with adaptive trials had extensive correspondence between drug sponsors and regulators regarding the adaptive designs, in some cases with regulators requiring revisions or alterations to research designs. Conclusions Wider use of adaptive designs will necessitate new drug application sponsors to engage with regulatory scientists during planning and conduct of the trials. Investigators need to more consistently report protections intended to preserve confidentiality and minimise potential operational bias during interim analysis. PMID:29440155
Horn, Austin R; Weijer, Charles; Hey, Spencer Phillips; Brehaut, Jamie; Fergusson, Dean A; Goldstein, Cory E; Grimshaw, Jeremy; Taljaard, Monica
2018-04-27
The ethics of the Flexibility In duty hour Requirements for Surgical Trainees (FIRST) trial have been vehemently debated. Views on the ethics of the FIRST trial range from it being completely unethical to wholly unproblematic. The FIRST trial illustrates the complex ethical challenges posed by cluster randomised trials (CRTs) of policy interventions involving healthcare professionals. In what follows, we have three objectives. First, we critically review the FIRST trial controversy, finding that commentators have failed to sufficiently identify and address many of the relevant ethical issues. The 2012 Ottawa Statement on the Ethical Design and Conduct of Cluster Randomized Trials provides researchers and research ethics committees with specific guidance for the ethical design and conduct of CRTs. Second, we aim to demonstrate how the Ottawa Statement provides much-needed clarity to the ethical issues in the FIRST trial, including: research participant identification; consent requirements; gatekeeper roles; benefit-harm analysis and identification of vulnerable participants. We nonetheless also find that the FIRST trial raises ethical issues not adequately addressed by the Ottawa Statement. Hence, third and finally, we raise important questions requiring further ethical analysis and guidance, including: Does clinical equipoise apply to policy interventions with little or no evidence-base? Do healthcare providers have an obligation to participate in research? Does the power-differential in certain healthcare settings render healthcare providers vulnerable to duress and coercion to participant in research? If so, what safeguards might be implemented to protect providers, while allowing important research to proceed? © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.
2014-01-01
Background Many patients with cervical disc disease require leave from work, due to long-lasting, complex symptoms, including chronic pain and reduced levels of physical and psychological function. Surgery on a few segmental levels might be expected to resolve disc-specific pain and reduce neurological deficits, but not the non-specific neck pain and the frequent illness. No study has investigated whether post-surgery physiotherapy might improve the outcome of surgery. The main purpose of this study was to evaluate whether a well-structured rehabilitation programme might add benefit to the customary post-surgical treatment for cervical disc disease, with respect to function, disability, work capability, and cost effectiveness. Methods/Design This study was designed as a prospective, randomised, controlled, multi-centre study. An independent, blinded investigator will compare two alternatives of rehabilitation. We will include 200 patients of working age, with cervical disc disease confirmed by clinical findings and symptoms of cervical nerve root compression. After providing informed consent, study participants will be randomised to one of two alternative physiotherapy regimes; (A) customary treatment (information and advice on a specialist clinic); or (B) customary treatment plus active physiotherapy. Physiotherapy will follow a standardised, structured programme of neck-specific exercises combined with a behavioural approach. All patients will be evaluated both clinically and subjectively (with questionnaires) before surgery and at 6 weeks, 3 months, 6 months, 12 months, and 24 months after surgery. The main outcome variable will be neck-specific disability. Cost-effectiveness will also be calculated. Discussion We anticipate that the results of this study will provide evidence to support physiotherapeutic rehabilitation applied after surgery for cervical radiculopathy due to cervical disc disease. Trial registration ClinicalTrials.gov identifier: NCT01547611 PMID:24502414
Haas, Marilyn C.; Bodner, Eric V.; Brown, Cynthia J.; Bryan, David; Buys, David R.; Keita, Akilah Dulin; Flagg, Lee Anne; Goss, Amy; Gower, Barbara; Hovater, Martha; Hunter, Gary; Ritchie, Christine S.; Roth, David L.; Wingo, Brooks C.; Ard, Jamy; Locher, Julie L.
2014-01-01
We conducted a study designed to evaluate whether the benefits of intentional weight loss exceed the potential risks in a group of community-dwelling, obese, older adults who were at increased risk for cardiometabolic disease. The CROSSROADS trial used a prospective randomized controlled design to compare the effects of changes in diet composition alone or combined with weight loss with an exercise only control intervention on body composition and adipose tissue deposition (Specific Aim #1: To compare the effects of changes in diet composition alone or combined with weight loss with an exercise only control intervention on body composition, namely visceral adipose tissue (VAT)), cardiometabolic disease risk (Specific Aim #2: To compare the effects of a change in diet composition alone or combined with weight loss with an exercise only control intervention on cardiometabolic disease risk), functional status and quality of life (Specific Aim #3: To compare the effects of a change in diet composition alone or combined with weight loss with an exercise only control intervention on functional status and quality of life). Participants were randomly assigned to one of three groups: Exercise Only (Control) Intervention, Exercise + Diet Quality + Weight Maintenance Intervention, or Exercise + Diet Quality + Weight Loss Intervention. CROSSROADS utilized a lifestyle intervention approach consisting of exercise, dietary, and behavioral components. The development and implementation of the CROSSROADS protocol, including a description of the methodology, detailing specific elements of the lifestyle intervention, assurances of treatment fidelity, and participant retention; outcome measures and adverse event monitoring; as well as unique data management features of the trial results, are presented in this article. PMID:25424512
Haas, Marilyn C; Bodner, Eric V; Brown, Cynthia J; Bryan, David; Buys, David R; Keita, Akilah Dulin; Flagg, Lee Anne; Goss, Amy; Gower, Barbara; Hovater, Martha; Hunter, Gary; Ritchie, Christine S; Roth, David L; Wingo, Brooks C; Ard, Jamy; Locher, Julie L
2014-01-01
We conducted a study designed to evaluate whether the benefits of intentional weight loss exceed the potential risks in a group of community-dwelling obese older adults who were at increased risk for cardiometabolic disease. The CROSSROADS trial used a prospective randomized controlled design to compare the effects of changes in diet composition alone or combined with weight loss with an exercise only control intervention on body composition and adipose tissue deposition (Specific Aim #1: To compare the effects of changes in diet composition alone or combined with weight loss with an exercise only control intervention on body composition, namely visceral adipose tissue), cardiometabolic disease risk (Specific Aim #2: To compare the effects of a change in diet composition alone or combined with weight loss with an exercise only control intervention on cardiometabolic disease risk), and functional status and quality of life (Specific Aim #3: To compare the effects of a change in diet composition alone or combined with weight loss with an exercise only control intervention on functional status and quality of life). Participants were randomly assigned to one of three groups: Exercise Only (Control) Intervention, Exercise + Diet Quality + Weight Maintenance Intervention, or Exercise + Diet Quality + Weight Loss Intervention. CROSSROADS utilized a lifestyle intervention approach consisting of exercise, dietary, and behavioral components. The development and implementation of the CROSSROADS protocol, including a description of the methodology, detailing specific elements of the lifestyle intervention, assurances of treatment fidelity, and participant retention; outcome measures and adverse event monitoring; as well as unique data management features of the trial results, are presented in this article.
Jacchia, Sara; Nardini, Elena; Bassani, Niccolò; Savini, Christian; Shim, Jung-Hyun; Trijatmiko, Kurniawan; Kreysa, Joachim; Mazzara, Marco
2015-05-27
This article describes the international validation of the quantitative real-time polymerase chain reaction (PCR) detection method for Golden Rice 2. The method consists of a taxon-specific assay amplifying a fragment of rice Phospholipase D α2 gene, and an event-specific assay designed on the 3' junction between transgenic insert and plant DNA. We validated the two assays independently, with absolute quantification, and in combination, with relative quantification, on DNA samples prepared in haploid genome equivalents. We assessed trueness, precision, efficiency, and linearity of the two assays, and the results demonstrate that both the assays independently assessed and the entire method fulfill European and international requirements for methods for genetically modified organism (GMO) testing, within the dynamic range tested. The homogeneity of the results of the collaborative trial between Europe and Asia is a good indicator of the robustness of the method.
Renfro, L. A.; Sargent, D. J.
2017-01-01
Abstract In recent years, cancers once viewed as relatively homogeneous in terms of organ location and treatment strategy are now better understood to be increasingly heterogeneous across biomarker and genetically defined patient subgroups. This has produced a shift toward development of biomarker-targeted agents during a time when funding for cancer research has been limited; as a result, the need for improved operational efficiency in studying many agent-and-target combinations in parallel has emerged. Platform trials, basket trials, and umbrella trials are new approaches to clinical research driven by this need for enhanced efficiency in the modern era of increasingly specific cancer subpopulations and decreased resources to study treatments for individual cancer subtypes in a traditional way. In this review, we provide an overview of these new types of clinical trial designs, including discussions of motivation for their use, recommended terminology, examples, and challenges encountered in their application. PMID:28177494
78 FR 58318 - Clinical Trial Design for Intravenous Fat Emulsion Products; Public Workshop
Federal Register 2010, 2011, 2012, 2013, 2014
2013-09-23
...] Clinical Trial Design for Intravenous Fat Emulsion Products; Public Workshop AGENCY: Food and Drug... announcing a 1-day public workshop entitled ``Clinical Trial Design for Intravenous Fat Emulsion Products.'' This workshop will provide a forum to discuss trial design of clinical trials intended to support...
Rothmann, Mark
2005-01-01
When testing the equality of means from two different populations, a t-test or large sample normal test tend to be performed. For these tests, when the sample size or design for the second sample is dependent on the results of the first sample, the type I error probability is altered for each specific possibility in the null hypothesis. We will examine the impact on the type I error probabilities for two confidence interval procedures and procedures using test statistics when the design for the second sample or experiment is dependent on the results from the first sample or experiment (or series of experiments). Ways for controlling a desired maximum type I error probability or a desired type I error rate will be discussed. Results are applied to the setting of noninferiority comparisons in active controlled trials where the use of a placebo is unethical.
Zhou, Yinghui; Whitehead, John; Korhonen, Pasi; Mustonen, Mika
2008-03-01
Bayesian decision procedures have recently been developed for dose escalation in phase I clinical trials concerning pharmacokinetic responses observed in healthy volunteers. This article describes how that general methodology was extended and evaluated for implementation in a specific phase I trial of a novel compound. At the time of writing, the study is ongoing, and it will be some time before the sponsor will wish to put the results into the public domain. This article is an account of how the study was designed in a way that should prove to be safe, accurate, and efficient whatever the true nature of the compound. The study involves the observation of two pharmacokinetic endpoints relating to the plasma concentration of the compound itself and of a metabolite as well as a safety endpoint relating to the occurrence of adverse events. Construction of the design and its evaluation via simulation are presented.
Optimal design in pediatric pharmacokinetic and pharmacodynamic clinical studies.
Roberts, Jessica K; Stockmann, Chris; Balch, Alfred; Yu, Tian; Ward, Robert M; Spigarelli, Michael G; Sherwin, Catherine M T
2015-03-01
It is not trivial to conduct clinical trials with pediatric participants. Ethical, logistical, and financial considerations add to the complexity of pediatric studies. Optimal design theory allows investigators the opportunity to apply mathematical optimization algorithms to define how to structure their data collection to answer focused research questions. These techniques can be used to determine an optimal sample size, optimal sample times, and the number of samples required for pharmacokinetic and pharmacodynamic studies. The aim of this review is to demonstrate how to determine optimal sample size, optimal sample times, and the number of samples required from each patient by presenting specific examples using optimal design tools. Additionally, this review aims to discuss the relative usefulness of sparse vs rich data. This review is intended to educate the clinician, as well as the basic research scientist, whom plan on conducting a pharmacokinetic/pharmacodynamic clinical trial in pediatric patients. © 2015 John Wiley & Sons Ltd.
Koek, Mayke B G; Buskens, Erik; Steegmans, Paul H A; van Weelden, Huib; Bruijnzeel-Koomen, Carla A F M; Sigurdsson, Vigfús
2006-08-01
Home ultraviolet B (UVB) treatment is a much-debated treatment, especially with regard to effectiveness, safety and side effects. However, it is increasingly being prescribed, especially in the Netherlands. Despite ongoing discussions, no randomised research has been performed, and only two studies actually compare two groups of patients. Thus, firm evidence to support or discourage the use of home UVB phototherapy has not yet been obtained. This is the goal of the present study, the PLUTO study (Dutch acronym for "national trial on home UVB phototherapy for psoriasis"). We designed a pragmatic randomised single-blind multi-centre trial. This trial is designed to evaluate the impact of home UVB treatment versus UVB phototherapy in a hospital outpatient clinic as to effectiveness, quality of life and cost-effectiveness. In total 196 patients with psoriasis who were clinically eligible for UVB phototherapy were included. Normally 85% of the patients treated with UVB show a relevant clinical response. With a power of 80% and a 0.05 significance level it will be possible to detect a reduction in effectiveness of 15%. Effectiveness will be determined by calculating differences in the Psoriasis Area and Severity Index (PASI) and the Self Administered PASI (SAPASI) scores. Quality of life is measured using several validated generic questionnaires and a disease-specific questionnaire. Other outcome measures include costs, side effects, dosimetry, concomitant use of medication and patient satisfaction. Patients are followed throughout the therapy and for 12 months thereafter. The study is no longer recruiting patients, and is expected to report in 2006. In the field of home UVB phototherapy this trial is the first randomised parallel group study. As such, this trial addresses the weaknesses encountered in previous studies. The pragmatic design ensures that the results can be well generalised to the target population. Because, in addition to effectiveness, aspects such as quality of life and cost-effectiveness are also taken into consideration, this study will produce valuable evidence to either support or discourage prescription of home UVB phototherapy. Current controlled trials/Nederlands Trial register: ISRCTN83025173. Clinicaltrials.gov: NCT00150930.
Verbal Learning and Memory Functions in Adolescents with Reading Disabilities
ERIC Educational Resources Information Center
Oyler, James D.; Obrzut, John E.; Asbjornsen, Arve E.
2012-01-01
The authors of this current study compared the memory performance of adolescent students with specific reading disabilities (RD) with that of typical adolescent readers on a newly developed verbal learning test, the "Bergen-Tucson Verbal Learning Test" (BTVLT). This multiple trial test was designed to measure memory acquisition,…
Turner, E L; Metcalfe, C; Donovan, J L; Noble, S; Sterne, J A C; Lane, J A; Avery, K N; Down, L; Walsh, E; Davis, M; Ben-Shlomo, Y; Oliver, S E; Evans, S; Brindle, P; Williams, N J; Hughes, L J; Hill, E M; Davies, C; Ng, S Y; Neal, D E; Hamdy, F C; Martin, R M
2014-06-10
Screening for prostate cancer continues to generate controversy because of concerns about over-diagnosis and unnecessary treatment. We describe the rationale, design and recruitment of the Cluster randomised triAl of PSA testing for Prostate cancer (CAP) trial, a UK-wide cluster randomised controlled trial investigating the effectiveness and cost-effectiveness of prostate-specific antigen (PSA) testing. Seven hundred and eighty-five general practitioner (GP) practices in England and Wales were randomised to a population-based PSA testing or standard care and then approached for consent to participate. In the intervention arm, men aged 50-69 years were invited to undergo PSA testing, and those diagnosed with localised prostate cancer were invited into a treatment trial. Control arm practices undertook standard UK management. All men were flagged with the Health and Social Care Information Centre for deaths and cancer registrations. The primary outcome is prostate cancer mortality at a median 10-year-follow-up. Among randomised practices, 271 (68%) in the intervention arm (198,114 men) and 302 (78%) in the control arm (221,929 men) consented to participate, meeting pre-specified power requirements. There was little evidence of differences between trial arms in measured baseline characteristics of the consenting GP practices (or men within those practices). The CAP trial successfully met its recruitment targets and will make an important contribution to international understanding of PSA-based prostate cancer screening.
Knight, Danica K; Belenko, Steven; Wiley, Tisha; Robertson, Angela A; Arrigona, Nancy; Dennis, Michael; Bartkowski, John P; McReynolds, Larkin S; Becan, Jennifer E; Knudsen, Hannah K; Wasserman, Gail A; Rose, Eve; DiClemente, Ralph; Leukefeld, Carl
2016-04-29
The purpose of this paper is to describe the Juvenile Justice-Translational Research on Interventions for Adolescents in the Legal System (JJ-TRIALS) study, a cooperative implementation science initiative involving the National Institute on Drug Abuse, six research centers, a coordinating center, and Juvenile Justice Partners representing seven US states. While the pooling of resources across centers enables a robust implementation study design involving 36 juvenile justice agencies and their behavioral health partner agencies, co-producing a study protocol that has potential to advance implementation science, meets the needs of all constituencies (funding agency, researchers, partners, study sites), and can be implemented with fidelity across the cooperative can be challenging. This paper describes (a) the study background and rationale, including the juvenile justice context and best practices for substance use disorders, (b) the selection and use of an implementation science framework to guide study design and inform selection of implementation components, and (c) the specific study design elements, including research questions, implementation interventions, measurement, and analytic plan. The JJ-TRIALS primary study uses a head-to-head cluster randomized trial with a phased rollout to evaluate the differential effectiveness of two conditions (Core and Enhanced) in 36 sites located in seven states. A Core strategy for promoting change is compared to an Enhanced strategy that incorporates all core strategies plus active facilitation. Target outcomes include improvements in evidence-based screening, assessment, and linkage to substance use treatment. Contributions to implementation science are discussed as well as challenges associated with designing and deploying a complex, collaborative project. NCT02672150 .
Methodology of phase II clinical trials in metastatic elderly breast cancer: a literature review.
Cabarrou, B; Mourey, L; Dalenc, F; Balardy, L; Kanoun, D; Roché, H; Boher, J M; Rougé-Bugat, M E; Filleron, Thomas
2017-08-01
As the incidence of invasive breast cancer will increase with age, the number of elderly patients with a diagnosis metastatic breast cancer will also rise. But the use of cytotoxic drugs in elderly metastatic breast cancer patients is not systematic and is dreaded by medical oncologists. The need for prospective oncologic data from this population seems increasingly obvious. The main objective of this review is to investigate design and characteristics of phase II trials that assess activity and feasibility of chemotherapies in elderly advanced/metastatic breast cancer patients. An electronic search in PUBMED allowed us to retrieve articles published in English language on phase II trials in elderly metastatic breast cancer between January 2002 and May 2016. Sixteen publications were finally included in this review. The primary endpoint was a simple, a composite, and a co-primary endpoints in 11, three, and two studies, respectively. Efficacy was the primary objective in 15 studies: simple (n = 10), composite (n = 3), co-primary endpoints (n = 2). Composite or co-primary endpoints combined efficacy and toxicity. Thirteen studies used multistage designs. Only five studies evaluated the feasibility, i.e., to jointly assess efficacy and tolerance to treatment (toxicity, quality of life, etc) as primary endpoint. Development of elderly specific phase III clinical trials might be challenging, it therefore seems essential to conduct phase II clinical trials evaluating jointly efficacy and toxicity in a well-defined geriatric population. Use of multistage designs that take into account heterogeneity would allow to identify a subpopulation at interim analysis and to reduce the number of patients exposed to an inefficient or a toxic treatment regimen. It is crucial to evaluate new therapies (targeted therapies, immunotherapies) using adequate methodologies (Study design, endpoint).
2017-03-03
biomechanical gait state changes within prolonged exercise or training events. II. MATERIAL AND METHODS A. Instrumented Insert Design We developed a...beginning and end of each data collection trial using a user interface designed specifically for this purpose in MATLAB. F. Calibration Proces:Static...consisted of walking for several minutes indoors (thin carpeted surface on concrete) and outdoors on several different surfaces ( pavement , gravel and
Perlmutter, A S; Tran, V-T; Dechartres, A; Ravaud, P
2017-04-01
Protocols are often unavailable to peer-reviewers and readers. To detect outcome reporting bias (ORB), readers usually have to resort to publicly available descriptions of study design such as public clinical trial registries. We compared primary outcomes in protocols, ClinicalTrials.gov and publications of oncology trials and evaluated the use of ClinicalTrials.gov as compared with protocols in detecting discrepancies between planned and published outcomes. We searched for phase III oncology trials registered in ClinicalTrials.gov and published in the Journal of Clinical Oncology and New England Journal of Medicine between January 2014 and June 2015. We extracted primary outcomes reported in the protocol, ClinicalTrials.gov and the publication. First, we assessed the quality of primary outcome descriptions by using a published framework. Second, we evaluated modifications of primary outcomes between each source. Finally, we evaluated the agreement, specificity and sensitivity of detecting modifications between planned and published outcomes by using protocols or ClinicalTrials.gov. We included 65 trials, with 81 primary outcomes common among the 3 sources. The proportion of primary outcomes reporting all items from the framework was 73%, 22%, and 75% for protocols, ClinicalTrials.gov and publications, respectively. Eight (12%) trials presented a discrepancy between primary outcomes reported in the protocol and in the publication. Twelve (18.5%) trials presented a discrepancy between primary outcomes registered at ClinicalTrials.gov and in publications. We found a moderate agreement in detecting discrepant reporting of outcomes by using protocols or ClinicalTrials.gov [κ = 0.53, 95% confidence interval (0.25-0.81)]. Using ClinicalTrials.gov to detect discrepant reporting of outcomes showed high specificity (89.5%) but lacked sensitivity (75%) as compared with use of protocols. In oncology trials, primary outcome descriptions in ClinicalTrials.gov are often of low quality and may not reflect what is in the protocol, thus limiting the detection of modifications between planned and published outcomes. © The Author 2016. Published by Oxford University Press on behalf of the European Society for Medical Oncology. All rights reserved. For permissions, please email: journals.permissions@oup.com.
Guetterman, Timothy C; Fetters, Michael D; Mawocha, Samkeliso; Legocki, Laurie J; Barsan, William G; Lewis, Roger J; Berry, Donald A; Meurer, William J
2017-01-01
Objectives: Clinical trials are complicated, expensive, time-consuming, and frequently do not lead to discoveries that improve the health of patients with disease. Adaptive clinical trials have emerged as a methodology to provide more flexibility in design elements to better answer scientific questions regarding whether new treatments are efficacious. Limited observational data exist that describe the complex process of designing adaptive clinical trials. To address these issues, the Adaptive Designs Accelerating Promising Treatments Into Trials project developed six, tailored, flexible, adaptive, phase-III clinical trials for neurological emergencies, and investigators prospectively monitored and observed the processes. The objective of this work is to describe the adaptive design development process, the final design, and the current status of the adaptive trial designs that were developed. Methods: To observe and reflect upon the trial development process, we employed a rich, mixed methods evaluation that combined quantitative data from visual analog scale to assess attitudes about adaptive trials, along with in-depth qualitative data about the development process gathered from observations. Results: The Adaptive Designs Accelerating Promising Treatments Into Trials team developed six adaptive clinical trial designs. Across the six designs, 53 attitude surveys were completed at baseline and after the trial planning process completed. Compared to baseline, the participants believed significantly more strongly that the adaptive designs would be accepted by National Institutes of Health review panels and non-researcher clinicians. In addition, after the trial planning process, the participants more strongly believed that the adaptive design would meet the scientific and medical goals of the studies. Conclusion: Introducing the adaptive design at early conceptualization proved critical to successful adoption and implementation of that trial. Involving key stakeholders from several scientific domains early in the process appears to be associated with improved attitudes towards adaptive designs over the life cycle of clinical trial development. PMID:29085638
Robb, Sheri L; Burns, Debra S; Docherty, Sharron L; Haase, Joan E
2011-11-01
The Stories and Music for Adolescent/Young Adult Resilience during Transplant (SMART) study (R01NR008583; U10CA098543; U10CA095861) is an ongoing multi-site Children's Oncology Group randomized clinical trial testing the efficacy of a therapeutic music video intervention for adolescents/young adults (11-24 years of age) with cancer undergoing stem cell transplant. Treatment fidelity strategies from our trial are consistent with the National Institutes of Health (NIH) Behavior Change Consortium Treatment Fidelity Workgroup (BCC) recommendations and provide a successful working model for treatment fidelity implementation in a large, multi-site behavioral intervention study. In this paper, we summarize 20 specific treatment fidelity strategies used in the SMART trial and how these strategies correspond with NIH BCC recommendations in five specific areas: (1) study design, (2) training providers, (3) delivery of treatment, (4) receipt of treatment, and (5) enactment of treatment skills. Increased use and reporting of treatment fidelity procedures is essential in advancing the reliability and validity of behavioral intervention research. The SMART trial provides a strong model for the application of fidelity strategies to improve scientific findings and addresses the absence of published literature, illustrating the application of BCC recommendations in behavioral intervention studies. Copyright © 2010 John Wiley & Sons, Ltd.
Reinventing clinical trials: a review of innovative biomarker trial designs in cancer therapies.
Lin, Ja-An; He, Pei
2015-06-01
Recently, new clinical trial designs involving biomarkers have been studied and proposed in cancer clinical research, in the hope of incorporating the rapid growing basic research into clinical practices. Journal articles related to various biomarkers and their role in cancer clinical trial, articles and books about statistical issues in trial design, and regulatory website, documents, and guidance for submission of targeted cancer therapies. The drug development process involves four phases. The confirmatory Phase III is essential in regulatory approval of a special treatment. Regulatory agency has restrictions on confirmatory trials 'using adaptive designs'. No rule of thumb to pick the most appropriate design for biomarker-related trials. Statistical issues to solve in new designs. Regulatory acceptance of the 'newly proposed trial designs'. Biomarker-related trial designs that can resolve the statistical issues and satisfy the regulatory requirement. © The Author 2015. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
LOCHER, JULIE L.; BALES, CONNIE W.; ELLIS, AMY C.; LAWRENCE, JEANNINE C.; NEWTON, LAURA; RITCHIE, CHRISTINE S.; ROTH, DAVID L.; BUYS, DAVID L.; VICKERS, KRISTIN S.
2012-01-01
We conducted a study designed to evaluate the efficacy and feasibility of a multilevel self-management intervention to improve nutritional intake in a group of older adults receiving Medicare home health services who were at especially high risk for experiencing undernutrition. The Behavioral Nutrition Intervention for Community Elders (B-NICE) trial used a prospective randomized controlled design to determine whether individually tailored counseling focused on social and behavioral aspects of eating resulted in increased caloric intake and improved nutrition-related health outcomes in a high-risk population of older adults. The study was guided by the theoretical approaches of the Ecological Model and Social Cognitive Theory. The development and implementation of the B-NICE protocol, including the theoretical framework, methodology, specific elements of the behavioral intervention, and assurances of the treatment fidelity, as well as the health policy implications of the trial results, are presented in this article. PMID:22098180
Crisp, Adam; Miller, Sam; Thompson, Douglas; Best, Nicky
2018-04-10
All clinical trials are designed for success of their primary objectives. Hence, evaluating the probability of success (PoS) should be a key focus at the design stage both to support funding approval from sponsor governance boards and to inform trial design itself. Use of assurance-that is, expected success probability averaged over a prior probability distribution for the treatment effect-to quantify PoS of a planned study has grown across the industry in recent years, and has now become routine within the authors' company. In this paper, we illustrate some of the benefits of systematically adopting assurance as a quantitative framework to support decision making in drug development through several case-studies where evaluation of assurance has proved impactful in terms of trial design and in supporting governance-board reviews of project proposals. In addition, we describe specific features of how the assurance framework has been implemented within our company, highlighting the critical role that prior elicitation plays in this process, and illustrating how the overall assurance calculation may be decomposed into a sequence of conditional PoS estimates which can provide greater insight into how and when different development options are able to discharge risk. Copyright © 2018 John Wiley & Sons, Ltd.
Enhancing clinical evidence by proactively building quality into clinical trials.
Meeker-O'Connell, Ann; Glessner, Coleen; Behm, Mark; Mulinde, Jean; Roach, Nancy; Sweeney, Fergus; Tenaerts, Pamela; Landray, Martin J
2016-08-01
Stakeholders across the clinical trial enterprise have expressed concern that the current clinical trial enterprise is unsustainable. The cost and complexity of trials have continued to increase, threatening our ability to generate reliable evidence essential for making appropriate decisions concerning the benefits and harms associated with clinical interventions. Overcoming this inefficiency rests on improving protocol design, trial planning, and quality oversight. The Clinical Trials Transformation Initiative convened a project to evaluate methods to prospectively build quality into the scientific and operational design of clinical trials ("quality-by-design"), such that trials are feasible to conduct and important errors are prevented rather than remediated. A working group evaluated aspects of trial design and oversight and developed the Clinical Trials Transformation Initiative quality-by-design principles document, outlining a series of factors generally relevant to the reliability of trial conclusions and to patient safety. These principles were then applied and further refined during a series of hands-on workshops to evaluate their utility in facilitating proactive, cross-functional dialogue, and decision-making about trial design and planning. Following these workshops, independent qualitative interviews were conducted with 19 workshop attendees to explore the potential challenges for implementing a quality-by-design approach to clinical trials. The Clinical Trials Transformation Initiative project team subsequently developed recommendations and an online resource guide to support implementation of this approach. The Clinical Trials Transformation Initiative quality-by-design principles provide a framework for assuring that clinical trials adequately safeguard participants and provide reliable information on which to make decisions on the effects of treatments. The quality-by-design workshops highlighted the value of active discussions incorporating the different perspectives within and external to an organization (e.g. clinical investigators, research site staff, and trial participants) in improving trial design. Workshop participants also recognized the value of focusing oversight on those aspects of the trial where errors would have a major impact on participant safety and reliability of results. Applying the Clinical Trials Transformation Initiative quality-by-design recommendations and principles should enable organizations to prioritize the most critical determinants of a trial's quality, identify non-essential activities that can be eliminated to streamline trial conduct and oversight, and formulate appropriate plans to define, avoid, mitigate, monitor, and address important errors. © The Author(s) 2016.
Can emergency medicine research benefit from adaptive design clinical trials?
Flight, Laura; Julious, Steven A; Goodacre, Steve
2017-04-01
Adaptive design clinical trials use preplanned interim analyses to determine whether studies should be stopped or modified before recruitment is complete. Emergency medicine trials are well suited to these designs as many have a short time to primary outcome relative to the length of recruitment. We hypothesised that the majority of published emergency medicine trials have the potential to use a simple adaptive trial design. We reviewed clinical trials published in three emergency medicine journals between January 2003 and December 2013. We determined the proportion that used an adaptive design as well as the proportion that could have used a simple adaptive design based on the time to primary outcome and length of recruitment. Only 19 of 188 trials included in the review were considered to have used an adaptive trial design. A total of 154/165 trials that were fixed in design had the potential to use an adaptive design. Currently, there seems to be limited uptake in the use of adaptive trial designs in emergency medicine despite their potential benefits to save time and resources. Failing to take advantage of adaptive designs could be costly to patients and research. It is recommended that where practical and logistical considerations allow, adaptive designs should be used for all emergency medicine clinical trials. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.
Therapeutic Gene Editing Safety and Specificity.
Lux, Christopher T; Scharenberg, Andrew M
2017-10-01
Therapeutic gene editing is significant for medical advancement. Safety is intricately linked to the specificity of the editing tools used to cut at precise genomic targets. Improvements can be achieved by thoughtful design of nucleases and repair templates, analysis of off-target editing, and careful utilization of viral vectors. Advancements in DNA repair mechanisms and development of new generations of tools improve targeting of specific sequences while minimizing risks. It is important to plot a safe course for future clinical trials. This article reviews safety and specificity for therapeutic gene editing to spur dialogue and advancement. Copyright © 2017 Elsevier Inc. All rights reserved.
Unique Study Designs in Nephrology: N-of-1 Trials and Other Designs.
Samuel, Joyce P; Bell, Cynthia S
2016-11-01
Alternatives to the traditional parallel-group trial design may be required to answer clinical questions in special populations, rare conditions, or with limited resources. N-of-1 trials are a unique trial design which can inform personalized evidence-based decisions for the patient when data from traditional clinical trials are lacking or not generalizable. A concise overview of factorial design, cluster randomization, adaptive designs, crossover studies, and n-of-1 trials will be provided along with pertinent examples in nephrology. The indication for analysis strategies such as equivalence and noninferiority trials will be discussed, as well as analytic pitfalls. Copyright © 2016 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.
Burdick, Katherine E.; Ketter, Terence A.; Goldberg, Joseph F.; Calabrese, Joseph R.
2015-01-01
OBJECTIVE Neurocognitive impairment in schizophrenia has been recognized for more than a century. In contrast, only recently have significant neurocognitive deficits been recognized in bipolar disorder. Converging data suggest the importance of cognitive problems in relation to quality of life in bipolar disorder, highlighting the need for treatment and prevention efforts targeting cognition in bipolar patients. Future treatment trials targeting cognitive deficits will be met with methodological challenges due to the inherent complexity and heterogeneity of the disorder, including significant diagnostic comorbidities, the episodic nature of the illness, frequent use of polypharmacy, cognitive heterogeneity, and a lack of consensus regarding measurement of cognition and outcome in bipolar patients. Guidelines for use in designing future trials are needed. PARTICIPANTS The members of the consensus panel (each of the bylined authors) were selected based upon their expertise in bipolar disorder. Dr. Burdick is a neuropsychologist who has studied cognition in this illness for 15 years; Drs. Ketter, Calabrese, and Goldberg each bring considerable expertise in the treatment of bipolar disorder both within and outside of controlled clinical trials. This consensus statement was derived from work together at scientific meetings (e.g. symposium presention at the 2014 Annual meeting of the American Society of Clinical Psychopharmacology, among others) and ongoing discussions by conference call. With the exception of the public presentations on this topic, these meetings were closed to outside participants. EVIDENCE A literature review was undertaken by the authors to identify illness-specific challenges relevant to the design and conduct of treatment trials targeting neurocognition in bipolar disorder. Expert opinion from each of the authors guided the consensus recommendations. CONSENSUS PROCESS Consensus recommendations, reached by unanimous opinion of the authors, are provided here as a preliminary guide for future trial design. Recommendations comprise exclusion of certain syndromal level comorbid diagnoses and current affective instability, restrictions on numbers and types of medications, and use of pre-screening assessment to ensure enrollment of subjects with adequate objective evidence of baseline cognitive impairment. CONCLUSIONS Clinical trials to address cognitive deficits in bipolar disorder face distinctive design challenges. As such trials move from proof-of-concept to confirmation of clinical efficacy, it will be important to incorporate distinctive design modifications to adequately address these challenges and increase the likelihood of demonstrating cognitive remediation effects. The field is now primed to address these challenges and a comprehensive effort to formalize best practice guidelines will be a critically important next step. PMID:25830456
Calvert, Melanie; Kyte, Derek; Mercieca-Bebber, Rebecca; Slade, Anita; Chan, An-Wen; King, Madeleine T; Hunn, Amanda; Bottomley, Andrew; Regnault, Antoine; Chan, An-Wen; Ells, Carolyn; O'Connor, Daniel; Revicki, Dennis; Patrick, Donald; Altman, Doug; Basch, Ethan; Velikova, Galina; Price, Gary; Draper, Heather; Blazeby, Jane; Scott, Jane; Coast, Joanna; Norquist, Josephine; Brown, Julia; Haywood, Kirstie; Johnson, Laura Lee; Campbell, Lisa; Frank, Lori; von Hildebrand, Maria; Brundage, Michael; Palmer, Michael; Kluetz, Paul; Stephens, Richard; Golub, Robert M; Mitchell, Sandra; Groves, Trish
2018-02-06
Patient-reported outcome (PRO) data from clinical trials can provide valuable evidence to inform shared decision making, labeling claims, clinical guidelines, and health policy; however, the PRO content of clinical trial protocols is often suboptimal. The SPIRIT (Standard Protocol Items: Recommendations for Interventional Trials) statement was published in 2013 and aims to improve the completeness of trial protocols by providing evidence-based recommendations for the minimum set of items to be addressed, but it does not provide PRO-specific guidance. To develop international, consensus-based, PRO-specific protocol guidance (the SPIRIT-PRO Extension). The SPIRIT-PRO Extension was developed following the Enhancing Quality and Transparency of Health Research (EQUATOR) Network's methodological framework for guideline development. This included (1) a systematic review of existing PRO-specific protocol guidance to generate a list of potential PRO-specific protocol items (published in 2014); (2) refinements to the list and removal of duplicate items by the International Society for Quality of Life Research (ISOQOL) Protocol Checklist Taskforce; (3) an international stakeholder survey of clinical trial research personnel, PRO methodologists, health economists, psychometricians, patient advocates, funders, industry representatives, journal editors, policy makers, ethicists, and researchers responsible for evidence synthesis (distributed by 38 international partner organizations in October 2016); (4) an international Delphi exercise (n = 137 invited; October 2016 to February 2017); and (5) consensus meeting (n = 30 invited; May 2017). Prior to voting, consensus meeting participants were informed of the results of the Delphi exercise and given data from structured reviews evaluating the PRO protocol content of 3 defined samples of trial protocols. The systematic review identified 162 PRO-specific protocol recommendations from 54 sources. The ISOQOL Taskforce (n = 21) reduced this to 56 items, which were considered by 138 international stakeholder survey participants and 99 Delphi panelists. The final wording of the SPIRIT-PRO Extension was agreed on at a consensus meeting (n = 29 participants) and reviewed by external group of experts during a consultation period. Eleven extensions and 5 elaborations to the SPIRIT 2013 checklist were recommended for inclusion in clinical trial protocols in which PROs are a primary or key secondary outcome. Extension items focused on PRO-specific issues relating to the trial rationale, objectives, eligibility criteria, concepts used to evaluate the intervention, time points for assessment, PRO instrument selection and measurement properties, data collection plan, translation to other languages, proxy completion, strategies to minimize missing data, and whether PRO data will be monitored during the study to inform clinical care. The SPIRIT-PRO guidelines provide recommendations for items that should be addressed and included in clinical trial protocols in which PROs are a primary or key secondary outcome. Improved design of clinical trials including PROs could help ensure high-quality data that may inform patient-centered care.
Perrachione, Tyler K; Lee, Jiyeon; Ha, Louisa Y Y; Wong, Patrick C M
2011-07-01
Studies evaluating phonological contrast learning typically investigate either the predictiveness of specific pretraining aptitude measures or the efficacy of different instructional paradigms. However, little research considers how these factors interact--whether different students learn better from different types of instruction--and what the psychological basis for any interaction might be. The present study demonstrates that successfully learning a foreign-language phonological contrast for pitch depends on an interaction between individual differences in perceptual abilities and the design of the training paradigm. Training from stimuli with high acoustic-phonetic variability is generally thought to improve learning; however, we found high-variability training enhanced learning only for individuals with strong perceptual abilities. Learners with weaker perceptual abilities were actually impaired by high-variability training relative to a low-variability condition. A second experiment assessing variations on the high-variability training design determined that the property of this learning environment most detrimental to perceptually weak learners is the amount of trial-by-trial variability. Learners' perceptual limitations can thus override the benefits of high-variability training where trial-by-trial variability in other irrelevant acoustic-phonetic features obfuscates access to the target feature. These results demonstrate the importance of considering individual differences in pretraining aptitudes when evaluating the efficacy of any speech training paradigm. © 2011 Acoustical Society of America
Hellmich, Bernhard; Flossmann, Oliver; Gross, Wolfgang L; Bacon, Paul; Cohen‐Tervaert, Jan Willem; Guillevin, Loic; Jayne, David; Mahr, Alfred; Merkel, Peter A; Raspe, Heiner; Scott, David G I; Witter, James; Yazici, Hasan; Luqmani, Raashid A
2007-01-01
Objectives To develop the European League Against Rheumatism (EULAR) recommendations for conducting clinical studies and/or clinical trials in systemic vasculitis. Methods An expert consensus group was formed consisting of rheumatologists, nephrologists and specialists in internal medicine representing five European countries and the USA, a clinical epidemiologist and representatives from regulatory agencies. Using an evidence‐based and expert opinion‐based approach in accordance with the standardised EULAR operating procedures, the group identified nine topics for a systematic literature search through a modified Delphi technique. On the basis of research questions posed by the group, recommendations were derived for conducting clinical studies and/or clinical trials in systemic vasculitis. Results Based on the results of the literature research, the expert committee concluded that sufficient evidence to formulate guidelines on conducting clinical trials was available only for anti‐neutrophil cytoplasm antibody‐associated vasculitides (AAV). It was therefore decided to focus the recommendations on these diseases. Recommendations for conducting clinical trials in AAV were elaborated and are presented in this summary document. It was decided to consider vasculitis‐specific issues rather than general issues of trial methodology. The recommendations deal with the following areas related to clinical studies of vasculitis: definitions of disease, activity states, outcome measures, eligibility criteria, trial design including relevant end points, and biomarkers. A number of aspects of trial methodology were deemed important for future research. Conclusions On the basis of expert opinion, recommendations for conducting clinical trials in AAV were formulated. Furthermore, the expert committee identified a strong need for well‐designed research in non‐AAV systemic vasculitides. PMID:17170053
Mano, Junichi; Masubuchi, Tomoko; Hatano, Shuko; Futo, Satoshi; Koiwa, Tomohiro; Minegishi, Yasutaka; Noguchi, Akio; Kondo, Kazunari; Akiyama, Hiroshi; Teshima, Reiko; Kurashima, Takeyo; Takabatake, Reona; Kitta, Kazumi
2013-01-01
In this article, we report a novel real-time PCR-based analytical method for quantitation of the GM maize event LY038. We designed LY038-specific and maize endogenous reference DNA-specific PCR amplifications. After confirming the specificity and linearity of the LY038-specific PCR amplification, we determined the conversion factor required to calculate the weight-based content of GM organism (GMO) in a multilaboratory evaluation. Finally, in order to validate the developed method, an interlaboratory collaborative trial according to the internationally harmonized guidelines was performed with blind DNA samples containing LY038 at the mixing levels of 0, 0.5, 1.0, 5.0 and 10.0%. The precision of the method was evaluated as the RSD of reproducibility (RSDR), and the values obtained were all less than 25%. The limit of quantitation of the method was judged to be 0.5% based on the definition of ISO 24276 guideline. The results from the collaborative trial suggested that the developed quantitative method would be suitable for practical testing of LY038 maize.
Design of Phase II Non-inferiority Trials.
Jung, Sin-Ho
2017-09-01
With the development of inexpensive treatment regimens and less invasive surgical procedures, we are confronted with non-inferiority study objectives. A non-inferiority phase III trial requires a roughly four times larger sample size than that of a similar standard superiority trial. Because of the large required sample size, we often face feasibility issues to open a non-inferiority trial. Furthermore, due to lack of phase II non-inferiority trial design methods, we do not have an opportunity to investigate the efficacy of the experimental therapy through a phase II trial. As a result, we often fail to open a non-inferiority phase III trial and a large number of non-inferiority clinical questions still remain unanswered. In this paper, we want to develop some designs for non-inferiority randomized phase II trials with feasible sample sizes. At first, we review a design method for non-inferiority phase III trials. Subsequently, we propose three different designs for non-inferiority phase II trials that can be used under different settings. Each method is demonstrated with examples. Each of the proposed design methods is shown to require a reasonable sample size for non-inferiority phase II trials. The three different non-inferiority phase II trial designs are used under different settings, but require similar sample sizes that are typical for phase II trials.
Thompson, Jennifer A; Fielding, Katherine; Hargreaves, James; Copas, Andrew
2017-12-01
Background/Aims We sought to optimise the design of stepped wedge trials with an equal allocation of clusters to sequences and explored sample size comparisons with alternative trial designs. Methods We developed a new expression for the design effect for a stepped wedge trial, assuming that observations are equally correlated within clusters and an equal number of observations in each period between sequences switching to the intervention. We minimised the design effect with respect to (1) the fraction of observations before the first and after the final sequence switches (the periods with all clusters in the control or intervention condition, respectively) and (2) the number of sequences. We compared the design effect of this optimised stepped wedge trial to the design effects of a parallel cluster-randomised trial, a cluster-randomised trial with baseline observations, and a hybrid trial design (a mixture of cluster-randomised trial and stepped wedge trial) with the same total cluster size for all designs. Results We found that a stepped wedge trial with an equal allocation to sequences is optimised by obtaining all observations after the first sequence switches and before the final sequence switches to the intervention; this means that the first sequence remains in the control condition and the last sequence remains in the intervention condition for the duration of the trial. With this design, the optimal number of sequences is [Formula: see text], where [Formula: see text] is the cluster-mean correlation, [Formula: see text] is the intracluster correlation coefficient, and m is the total cluster size. The optimal number of sequences is small when the intracluster correlation coefficient and cluster size are small and large when the intracluster correlation coefficient or cluster size is large. A cluster-randomised trial remains more efficient than the optimised stepped wedge trial when the intracluster correlation coefficient or cluster size is small. A cluster-randomised trial with baseline observations always requires a larger sample size than the optimised stepped wedge trial. The hybrid design can always give an equally or more efficient design, but will be at most 5% more efficient. We provide a strategy for selecting a design if the optimal number of sequences is unfeasible. For a non-optimal number of sequences, the sample size may be reduced by allowing a proportion of observations before the first or after the final sequence has switched. Conclusion The standard stepped wedge trial is inefficient. To reduce sample sizes when a hybrid design is unfeasible, stepped wedge trial designs should have no observations before the first sequence switches or after the final sequence switches.
PROSTVAC® targeted immunotherapy candidate for prostate cancer.
Shore, Neal D
2014-01-01
Targeted immunotherapies represent a valid strategy for the treatment of metastatic castrate-resistant prostate cancer. A randomized, double-blind, Phase II clinical trial of PROSTVAC® demonstrated a statistically significant improvement in overall survival and a large, global, Phase III trial with overall survival as the primary end point is ongoing. PROSTVAC immunotherapy contains the transgenes for prostate-specific antigen and three costimulatory molecules (designated TRICOM). Research suggests that PROSTVAC not only targets prostate-specific antigen, but also other tumor antigens via antigen cascade. PROSTVAC is well tolerated and has been safely combined with other cancer therapies, including hormonal therapy, radiotherapy, another immunotherapy and chemotherapy. Even greater benefits of PROSTVAC may be recognized in earlier-stage disease and low-disease burden settings where immunotherapy can trigger a long-lasting immune response.
Neuroreflexotherapy for non-specific low-back pain.
Urrútia, G; Burton, A K; Morral, A; Bonfill, X; Zanoli, G
2004-01-01
Among the wide range of therapeutic alternatives proposed for the management of low-back pain (LBP), a less widely used technique from Spain, called neuroreflexotherapy (NRT) has claimed to show very favourable results, mainly in patients with chronic low-back pain. The aim of this review was to systematically assess the effectiveness of NRT for the treatment of non-specific LBP in adult patients, aged 16 to 65 years. A secondary objective was to compare NRT with other conventional interventions. We searched the Cochrane Central Register of Controlled Trials, MEDLINE, and EMBASE to October 1, 2002. Only randomised controlled trials (RCTs) of NRT for the treatment of patients with a clinical diagnosis of non-specific LBP were included. Two reviewers independently selected trials and extracted data using pre-designed forms. Because the outcome variables were not assessed in a homogenous way, it was not possible to pool the results to obtain an estimate of global effect, as initially planned. Three RCT were included, with a total of 125 subjects randomised to the control groups and 148 subjects receiving active NRT. Neuroreflexotherapy was the same in all three trials, while the control groups received sham-NRT in two trials and standard care in one. Two trials studied patients with chronic LBP, the third studied patients with a mix of chronic and sub-acute LBP. Clinical outcomes were measured in the short-term (15 to 60 days) in all three trials; in one trial, resource utilization was measured after one year. Individuals who received active NRT showed statistically significantly better outcomes than the control groups for measures of pain, degree of mobility, disability, medication use, consumption of resources and costs. No significant differences were observed for quality of life measures. Side effects were more frequently reported in the control groups during short-term follow-up, with no major side effects reported by those receiving active NRT. NRT appears to be a safe and effective intervention for the treatment of chronic non-specific LBP. The efficacy is less clear for sub-acute LBP. However, these results are limited to three trials conducted by a small number of specifically trained and experienced clinicians, in a limited geographical location. No data are available on the ease and time-frame needed to achieve that level of expertise. RCTs by other practitioners, in other locations, that replicate the effects reported in this review are needed before recommending a broader practice.
Tai, Bee-Choo; Grundy, Richard G; Machin, David
2010-04-01
In trials designed to delay or avoid irradiation among children with malignant brain tumor, although irradiation after disease progression is an important event, patients who have disease progression may decline radiotherapy (RT), or those without disease progression may opt for elective RT. To accurately describe the cumulative need for RT in such instances, it is crucial to account for these distinct events and to evaluate how each contributes to the delay or advancement of irradiation via a competing risks analysis. We describe the summary of competing events in such trials using competing risks methods based on cumulative incidence functions and Gray's test. The results obtained are contrasted with standard survival methods based on Kaplan-Meier curves, cause-specific hazard functions and log-rank test. The Kaplan-Meier method overestimates all event-specific rates. The cause-specific hazard analysis showed reduction in hazards for all events (A: RT after progression; B: no RT after progression; C: elective RT) among children with ependymoma. For event A, a higher cumulative incidence was reported for ependymoma. Although Gray's test failed to detect any difference (p = 0.331) between histologic subtypes, the log-rank test suggested marginal evidence (p = 0.057). Similarly, for event C, the log-rank test found stronger evidence of reduction in hazard among those with ependymoma (p = 0.005) as compared with Gray's test (p = 0.086). To evaluate treatment differences, failing to account for competing risks using appropriate methodology may lead to incorrect interpretations.
Randomized Multi-site Trial of the Job Seekers’ Workshop in Patients with Substance Use Disorders
Svikis, Dace S.; Keyser-Marcus, Lori; Stitzer, Maxine; Rieckmann, Traci; Safford, Lauretta; Loeb, Peter; Allen, Tim; Luna-Anderson, Carol; Back, Sudie E.; Cohen, Judith; DeBernardi, Michael A.; Dillard, Bruce; Forcehimes, Alyssa; Jaffee, William; Killeen, Therese; Kolodner, Ken; Levy, Michael; Pallas, Diane; Perl, Harold I.; Potter, Jennifer Sharpe; Provost, Scott; Reese, Karen; Sampson, Royce R.; Sepulveda, Allison; Snead, Ned; Wong, Conrad J.; Zweben, Joan
2012-01-01
Background Unemployment is associated with negative outcomes both during and after drug abuse treatment. Interventions designed to increase rates of employment may also improve drug abuse treatment outcomes. The purpose of this multi-site clinical trial was to evaluate the Job Seekers’ Workshop (JSW), a three session, manualized program designed to train patients in the skills needed to find and secure a job. Method Study participants were recruited through the NIDA Clinical Trials Network (CTN) from six psychosocial counseling (n=327) and five methadone maintenance (n=301) drug treatment programs. Participants were randomly assigned to either standard care (program-specific services plus brochure with local employment resources) (SC) or standard care plus JSW. Three 4-hr small group JSW sessions were offered weekly by trained JSW facilitators with ongoing fidelity monitoring. Results JSW and SC participants had similar 12- and 24-week results for the primary outcome measure (i.e., obtaining a new taxed job or enrollment in a training program), Specifically, one-fifth of participants at 12 weeks (20.1 – 24.3%) and nearly one-third at 24 weeks (31.4–31.9%) had positive outcomes, with “obtaining a new taxed job” accounting for the majority of cases. Conclusion JSW group participants did not have higher rates of employment/training than SC controls. Rates of job acquisition were modest for both groups, suggesting more intensive interventions may be needed. Alternate targets (e.g., enhancing patient motivation, training in job-specific skills) warrant further study as well. PMID:21802222
Response to Placebo in Clinical Epilepsy Trials - Old Ideas and New Insights
Goldenholz, Daniel M.; Goldenholz, Shira R
2016-01-01
Randomized placebo controlled trials are a mainstay of modern clinical epilepsy research; the success or failure of innovative therapies depends on proving superiority to a placebo. Consequently, understanding what drives response to placebo (including the “placebo effect”) may facilitate evaluation of new therapies. In this review, part one will explore observations about placebos specific to epilepsy, including the relatively higher placebo response in children, apparent increase in placebo response over the past several decades, geographic variation in placebo effect, relationship to baseline epilepsy characteristics, influence of nocebo on clinical trials, the possible increase in (SUDEP) in placebo arms of trials, and patterns that placebo responses appear to follow in individual patients. Part two will discuss the principal causes of placebo responses, including regression to the mean, anticipation, classical conditioning, the Hawthorne effect, expectations from symbols, and the natural history of disease. Included in part two will be a brief overview of recent advances using simulations from large datasets that have afforded new insights into causes of epilepsy related placebo responses. In part three, new developments in study design will be explored, including sequential parallel comparison, two-way enriched design, time to pre-randomization, delayed start, and cohort reduction techniques. PMID:26921852
2011-01-01
Background Low back pain (LBP), with high incidence and prevalence rate, is one of the most common reasons to consult the health system and is responsible for a significant amount of sick leave, leading to high health and social costs. The objective of the study is to assess the cost-effectiveness and cost-utility analysis of a multidisciplinary biopsychosocial educational group intervention (MBEGI) of non-specific sub-acute LBP in comparison with the usual care in the working population recruited in primary healthcare centres. Methods/design The study design is a cost-effectiveness and cost-utility analysis of a MBEGI in comparison with the usual care of non-specific sub-acute LBP. Measures on effectiveness and costs of both interventions will be obtained from a cluster randomised controlled clinical trial carried out in 38 Catalan primary health care centres, enrolling 932 patients between 18 and 65 years old with a diagnosis of non-specific sub-acute LBP. Effectiveness measures are: pharmaceutical treatments, work sick leave (% and duration in days), Roland Morris disability, McGill pain intensity, Fear Avoidance Beliefs (FAB) and Golberg Questionnaires. Utility measures will be calculated from the SF-12. The analysis will be performed from a social perspective. The temporal horizon is at 3 months (change to chronic LBP) and 12 months (evaluate the outcomes at long term). Assessment of outcomes will be blinded and will follow the intention-to-treat principle. Discussion We hope to demonstrate the cost-effectiveness and cost-utility of MBEGI, see an improvement in the patients' quality of life, achieve a reduction in the duration of episodes and the chronicity of non-specific low back pain, and be able to report a decrease in the social costs. If the intervention is cost-effectiveness and cost-utility, it could be applied to Primary Health Care Centres. Trial registration ISRCTN: ISRCTN58719694 PMID:21859489
Patient Engagement in Neurological Clinical Trials Design: A Conference Summary.
Cobb, Enesha M; Meurer, William; Harney, Deneil; Silbergleit, Robert; Lake, Bray Patrick; Clark, Christina; Gipson, Debbie; Barsan, William
2015-12-01
The conference objectives included educating patients and advocates about clinical trials, educating the clinical research community about patient perspectives on participating in clinical trial design, and identifying strategies to increase participation in clinical trial design for neurological disorders. Observations were noted during a 1-day conference attended by patients, patient advocates, clinical trial staff, and investigators. The conference offered didactic sessions, small, and large group discussions. Conference participants were patients, patient advocates, clinical trial staff, students, and investigators interested in engaging patients in clinical trial design for neurological disorders. Conference participants were asked to consider lessons learned that could increase patient engagement in clinical trial design. We found that there is growing interest in including patients in the design of clinical trials for neurological disorders. Several themes emerged on how to move forward: networking; the multifaceted roles of advocates in research; training and education; creating patient-researcher partnerships; and clinical trials regulation issues. The conference provided a forum for dialogue regarding stakeholder engagement in the design of clinical trials for neurological disorders. This experience provides a template for replication and dissemination of this conference and informs next steps to accelerate the pathway from dialogue to action. © 2015 Wiley Periodicals, Inc.
Laborda, Mario A; Polack, Cody W; Miguez, Gonzalo; Miller, Ralph R
2014-09-01
Recent data indicate that extinguished fear often returns when the testing conditions differ from those of treatment. Several manipulations including extensive extinction training, extinction in multiple contexts, and spacing the extinction trials and sessions reduce the return of fear. Moreover, extensive extinction and extinction in multiple contexts summate in reducing return of fear, and the spacing of the extinction trials and the spacing of extinction sessions summate in reducing return of fear. Here we evaluated whether these techniques also attenuate the context specificity of latent inhibition, and whether they summate to further decrease fear responding at test. In two experiments, with rats as subjects in a lick suppression preparation, we assessed the effects of massive CS preexposure, CS preexposure in multiple contexts, and of spacing the CS-preexposure trials and sessions, in reducing the context specificity of latent inhibition. Fear responding was attenuated by all four manipulations. Moreover, extensive CS preexposure in multiple contexts, and conjoint spacing of the CS-preexposure trials and sessions, were more effective in reducing the context specificity of latent inhibition than each manipulation alone. Our experimental designs evaluated degrees of context specificity of latent inhibition but omitted groups in which latent inhibition was assessed without a context shift away from the context of latent inhibition treatment. This precluded us from drawing conclusions concerning absolute (as opposed to relative) levels of recovery from latent inhibition. Techniques effective in decreasing the return of conditioned fear following extinction are also effective in decreasing the context specificity of latent inhibition in an animal model of anxiety. Fear and anxiety disorders might be prevented in anxious human participants with the same techniques used here, but that is still an empirical question. Copyright © 2014 Elsevier Ltd. All rights reserved.
Efficacy of Web-Based Personalized Normative Feedback: A Two-Year Randomized Controlled Trial
ERIC Educational Resources Information Center
Neighbors, Clayton; Lewis, Melissa A.; Atkins, David C.; Jensen, Megan M.; Walter, Theresa; Fossos, Nicole; Lee, Christine M.; Larimer, Mary E.
2010-01-01
Objective: Web-based brief alcohol interventions have the potential to reach a large number of individuals at low cost; however, few controlled evaluations have been conducted to date. The present study was designed to evaluate the efficacy of gender-specific versus gender-nonspecific personalized normative feedback (PNF) with single versus…
Helping Students Make Sense of Graphs: An Experimental Trial of SmartGraphs Software
ERIC Educational Resources Information Center
Zucker, Andrew; Kay, Rachel; Staudt, Carolyn
2014-01-01
Graphs are commonly used in science, mathematics, and social sciences to convey important concepts; yet students at all ages demonstrate difficulties interpreting graphs. This paper reports on an experimental study of free, Web-based software called SmartGraphs that is specifically designed to help students overcome their misconceptions regarding…
A proof of concept phase II non-inferiority criterion.
Neuenschwander, Beat; Rouyrre, Nicolas; Hollaender, Norbert; Zuber, Emmanuel; Branson, Michael
2011-06-15
Traditional phase III non-inferiority trials require compelling evidence that the treatment vs control effect bfθ is better than a pre-specified non-inferiority margin θ(NI) . The standard approach compares this margin to the 95 per cent confidence interval of the effect parameter. In the phase II setting, in order to declare Proof of Concept (PoC) for non-inferiority and proceed in the development of the drug, different criteria that are specifically tailored toward company internal decision making may be more appropriate. For example, less evidence may be needed as long as the effect estimate is reasonably convincing. We propose a non-inferiority design that addresses the specifics of the phase II setting. The requirements are that (1) the effect estimate be better than a critical threshold θ(C), and (2) the type I error with regard to θ(NI) is controlled at a pre-specified level. This design is compared with the traditional design from a frequentist as well as a Bayesian perspective, where the latter relies on the Level of Proof (LoP) metric, i.e. the probability that the true effect is better than effect values of interest. Clinical input is required to establish the value θ(C), which makes the design transparent and improves interactions within clinical teams. The proposed design is illustrated for a non-inferiority trial for a time-to-event endpoint in oncology. Copyright © 2011 John Wiley & Sons, Ltd.
2014-01-01
Background Preliminary research shows ginger may be an effective adjuvant treatment for chemotherapy-induced nausea and vomiting but significant limitations need to be addressed before recommendations for clinical practice can be made. Methods/Design In a double–blinded randomised-controlled trial, chemotherapy-naïve patients will be randomly allocated to receive either 1.2 g of a standardised ginger extract or placebo per day. The study medication will be administrated as an adjuvant treatment to standard anti-emetic therapy and will be divided into four capsules per day, to be consumed approximately every 4 hours (300 mg per capsule administered q.i.d) for five days during the first three cycles of chemotherapy. Acute, delayed, and anticipatory symptoms of nausea and vomiting will be assessed over this time frame using a valid and reliable questionnaire, with nausea symptoms being the primary outcome. Quality of life, nutritional status, adverse effects, patient adherence, cancer-related fatigue, and CINV-specific prognostic factors will also be assessed. Discussion Previous trials in this area have noted limitations. These include the inconsistent use of standardized ginger formulations and valid questionnaires, lack of control for anticipatory nausea and prognostic factors that may influence individual CINV response, and the use of suboptimal dosing regimens. This trial is the first to address these issues by incorporating multiple unique additions to the study design including controlling for CINV-specific prognostic factors by recruiting only chemotherapy-naïve patients, implementing a dosing schedule consistent with the pharmacokinetics of oral ginger supplements, and independently analysing ginger supplements before and after recruitment to ensure potency. Our trial will also be the first to assess the effect of ginger supplementation on cancer-related fatigue and nutritional status. Chemotherapy-induced nausea and vomiting are distressing symptoms experienced by oncology patients; this trial will address the significant limitations within the current literature and in doing so, will investigate the effect of ginger supplementation as an adjuvant treatment in modulating nausea and vomiting symptoms. Trial registration ANZCTR.org.au Identifier: ACTRN12613000120774. PMID:24712653
2010-01-01
Background Non-pharmacological treatment (NPT) is a useful treatment option in the management of hip or knee osteoarthritis. To our knowledge however, no studies have investigated the effect of NPT in patients with generalized osteoarthritis (GOA). The primary aim of this study is to compare the effectiveness of two currently existing health care programs with different intensity and mode of delivery on daily functioning in patients with GOA. The secondary objective is to compare the cost-effectiveness of both interventions. Methods/Design In this randomized, single blind, clinical trial with active controls, we aim to include 170 patients with GOA. The experimental intervention consist of six self-management group sessions provided by a multi-disciplinary team (occupational therapist, physiotherapist, dietician and specialized nurse). The active control group consists of two group sessions and four sessions by telephone, provided by a specialized nurse and physiotherapist. Both therapies last six weeks. Main study outcome is daily functioning during the first year after the treatment, assessed on the Health Assessment Questionnaire. Secondary outcomes are health related quality of life, specific complaints, fatigue, and costs. Illness cognitions, global perceived effect and self-efficacy, will also be assessed for a responder analysis. Outcome assessments are performed directly after the intervention, after 26 weeks and after 52 weeks. Discussion This article describes the design of a randomized, single blind, clinical trial with a one year follow up to compare the costs and effectiveness of two non-pharmacological interventions with different modes of delivery for patients with GOA. Trial registration Dutch Trial Register NTR2137 PMID:20594308
Design and Management of Field Trials of Transgenic Cereals
NASA Astrophysics Data System (ADS)
Bedő, Zoltán; Rakszegi, Mariann; Láng, László
The development of gene transformation systems has allowed the introgression of alien genes into plant genomes, thus providing a mechanism for broadening the genetic resources available to plant breeders. The design and the management of field trials vary according to the purpose for which transgenic cereals are developed. Breeders study the phenotypic and genotypic stability of transgenic plants, monitor the increase in homozygosity of transgenic genotypes under field conditions, and develop backcross generations to transfer the introduced genes into secondary transgenic cereal genotypes. For practical purposes, they may also multiply seed of the transgenic lines to produce sufficient amounts of grain for the detailed analysis of trait(s) of interest, to determine the field performance of transgenic lines, and to compare them with the non-transformed parental genotypes. Prior to variety registration, the Distinctness, Uniformity and Stability (DUS) tests and Value for Cultivation and Use (VCU) experiments are carried out in field trials. Field testing includes specific requirements for transgenic cereals to assess potential environmental risks. The capacity of the pollen to survive, establish and disseminate in the field test environment, the potential for gene transfer, the effects of products expressed by the introduced sequences and phenotypic and genotypic instability that might cause deleterious effects must all be specifically monitored, as required by EU Directives 2003/701/EC (1) on the release of genetically modified higher plants in the environment.
Biomarker-Guided Non-Adaptive Trial Designs in Phase II and Phase III: A Methodological Review
Antoniou, Miranta; Kolamunnage-Dona, Ruwanthi; Jorgensen, Andrea L.
2017-01-01
Biomarker-guided treatment is a rapidly developing area of medicine, where treatment choice is personalised according to one or more of an individual’s biomarker measurements. A number of biomarker-guided trial designs have been proposed in the past decade, including both adaptive and non-adaptive trial designs which test the effectiveness of a biomarker-guided approach to treatment with the aim of improving patient health. A better understanding of them is needed as challenges occur both in terms of trial design and analysis. We have undertaken a comprehensive literature review based on an in-depth search strategy with a view to providing the research community with clarity in definition, methodology and terminology of the various biomarker-guided trial designs (both adaptive and non-adaptive designs) from a total of 211 included papers. In the present paper, we focus on non-adaptive biomarker-guided trial designs for which we have identified five distinct main types mentioned in 100 papers. We have graphically displayed each non-adaptive trial design and provided an in-depth overview of their key characteristics. Substantial variability has been observed in terms of how trial designs are described and particularly in the terminology used by different authors. Our comprehensive review provides guidance for those designing biomarker-guided trials. PMID:28125057
Randomised studies of income supplementation: a lost opportunity to assess health outcomes.
Connor, J; Rodgers, A; Priest, P
1999-11-01
Despite the wealth of evidence linking low income to ill health, there is little information from randomised studies on how much and how quickly these risks can be reversed by improvements in income. To conduct a systematic review of randomised studies of income supplementation, with particular reference to health outcomes. Extensive searches of electronic databases and contact with previous authors. As well as searching for trials that were specifically designed to assess the effects of increased income, studies of winners and losers of lotteries were also sought: if winning is purely chance, such studies are, in effect, randomised trials of increased income. Ten relevant studies were identified, all conducted in North America, mostly in the late 1960s and 1970s. Five trials were designed to assess the effects of income supplementation on workforce participation and randomised a total of 10,000 families to 3-5 years of various combinations of minimum income guarantees and reduced tax rates. Two trials were designed to assess re-offending rates in recently released prisoners and randomised a total of 2400 people to 3-6 months of benefits. One trial was designed to assess housing allowances and randomised 3500 families to three years of income supplements. One trial assessed the health effects of 12 months of income supplementation in 54 people with severe mental illness. Finally, one study compared three groups of people who won different amounts of money in a state lottery. In all these studies the interventions resulted in increases in income of at least one fifth. However, no reliable analyses of health outcome data are available. Extensive opportunities to reliably assess the effects of increases in income on health outcomes have been missed. Such evidence might have increased the consideration of potential health effects during deliberations about policies that have major implications for income, such as taxation rates, benefit policies, and minimum wage levels. Randomised evidence could still be obtained with innovative new studies, such as trials of full benefit uptake or prospective studies of lottery winners in which different sized winnings are paid in monthly installments over many years.
Clinical trial quality: From supervision to collaboration and beyond.
Meeker-O'Connell, Ann; Glessner, Coleen
2018-02-01
Over the past decade, clinical trial quality has evolved from an after-the-fact, reactive activity to one focused on the important work of evidence generation from well-designed trials. This article explores the role the Clinical Trials Transformation Initiative has played in advancing quality as a core element of clinical trial design, through project work that initially focused on monitoring but evolved into a holistic, prospective, and comprehensive quality by design approach to clinical trial design and conduct.
Yap, Christina; Billingham, Lucinda J; Cheung, Ying Kuen; Craddock, Charlie; O'Quigley, John
2017-12-15
The ever-increasing pace of development of novel therapies mandates efficient methodologies for assessment of their tolerability and activity. Evidence increasingly support the merits of model-based dose-finding designs in identifying the recommended phase II dose compared with conventional rule-based designs such as the 3 + 3 but despite this, their use remains limited. Here, we propose a useful tool, dose transition pathways (DTP), which helps overcome several commonly faced practical and methodologic challenges in the implementation of model-based designs. DTP projects in advance the doses recommended by a model-based design for subsequent patients (stay, escalate, de-escalate, or stop early), using all the accumulated information. After specifying a model with favorable statistical properties, we utilize the DTP to fine-tune the model to tailor it to the trial's specific requirements that reflect important clinical judgments. In particular, it can help to determine how stringent the stopping rules should be if the investigated therapy is too toxic. Its use to design and implement a modified continual reassessment method is illustrated in an acute myeloid leukemia trial. DTP removes the fears of model-based designs as unknown, complex systems and can serve as a handbook, guiding decision-making for each dose update. In the illustrated trial, the seamless, clear transition for each dose recommendation aided the investigators' understanding of the design and facilitated decision-making to enable finer calibration of a tailored model. We advocate the use of the DTP as an integral procedure in the co-development and successful implementation of practical model-based designs by statisticians and investigators. Clin Cancer Res; 23(24); 7440-7. ©2017 AACR . ©2017 American Association for Cancer Research.
Bartholomew, John B; Jowers, Esbelle M; Errisuriz, Vanessa L; Vaughn, Sharon; Roberts, Gregory
2017-10-01
Active learning is designed to pair physical activity with the teaching of academic content. This has been shown to be a successful strategy to increase physical activity and improve academic performance. The existing designs have confounded academic lessons with physical activity. As a result, it is impossible to determine if the subsequent improvement in academic performance is due to: (1) physical activity, (2) the academic content of the active learning, or (3) the combination of academic material taught through physical activity. The Texas I-CAN project is a 3-arm, cluster randomized control trial in which 28 elementary schools were assigned to either control, math intervention, or spelling intervention. As a result, each intervention condition serves as an unrelated content control for the other arm of the trial, allowing the impact of physical activity to be separated from the content. That is, schools that perform only active math lessons provide a content control for the spelling schools on spelling outcomes. This also calculated direct observations of attention and behavior control following periods of active learning. This design is unique in its ability to separate the impact of physical activity, in general, from the combination of physical activity and specific academic content. This, in combination with the ability to examine both proximal and distal outcomes along with measures of time on task will do much to guide the design of future, school-based interventions. Copyright © 2017 Elsevier Inc. All rights reserved.
Grant, Jenna M
2016-04-01
Controversies about global clinical trials, particularly HIV trials, tend to be framed in terms of ethics. In this article, I explore debates about ethics in the Cambodia Pre-Exposure Prophylaxis trial, which was designed to test the safety and efficacy of tenofovir as a prevention for HIV infection. Bringing together studies of public participation in science with studies of bioethics, I show how activists around the Cambodian Pre-Exposure Prophylaxis trial circulated and provoked debates about standards of research ethics, as opposed to research methodology. This postcolonial bioethics was configured through the circulation of and debate about ethics guidelines, and historically and culturally specific relations of vulnerability and responsibility between foreigners and Cambodians and between Cambodian leaders and Cambodian subjects. I argue that this shift in the object of ethical concern, from the experimental human subject to the relation between subjects and researchers, illustrates how a postcolonial field of articulation reformulates classical bioethics.
The evolving landscape of therapeutic drug development for hepatocellular carcinoma.
Chong, Dawn Qingqing; Tan, Iain Beehuat; Choo, Su-Pin; Toh, Han Chong
2013-11-01
Currently, only one drug, sorafenib, is FDA approved for the treatment of advanced hepatocellular carcinoma (HCC), achieving modest objective response rates while still conferring an overall survival benefit. Unlike other solid tumors, no oncogenic addiction loops have been validated as clinically actionable targets in HCC. Outcomes of HCC could potentially be improved if critical molecular subclasses with distinct therapeutic vulnerabilities can be identified, biomarkers that predict recurrence or progression early can be determined and key epigenetic, genetic or microenvironment drivers that determine best response to a specific targeting treatment can be uncovered. Our group and others have examined the molecular heterogeneity of hepatocellular carcinoma. We have developed a panel of patient derived xenograft models to enable focused pre-clinical drug development of rationally designed therapies in specific molecular subgroups. We observed unique patterns, including synergies, of drug activity across our molecularly diverse HCC xenografts, pointing to specific therapeutic vulnerabilities for individual tumors. These efforts inform clinical trial designs and catalyze therapeutic development. It also argues for efficient strategic allocation of patients into appropriate enriched clinical trials. Here, we will discuss some of the recent important therapeutic studies in advanced HCC and also some of the potential strategies to optimize clinical therapeutic development moving forward. Copyright © 2013 Elsevier Inc. All rights reserved.
Can probiotics enhance vaccine-specific immunity in children and adults?
Kwak, J Y; Lamousé-Smith, E S N
2017-10-13
The growing use of probiotics by the general public has heightened the interest in understanding the role of probiotics in promoting health and preventing disease. General practitioners and specialists often receive inquiries from their patients regarding probiotic products and their use to ward off systemic infection or intestinal maladies. Enhanced immune function is among the touted health benefits conferred by probiotics but has not yet been fully established. Results from recent clinical trials in adults suggest a potential role for probiotics in enhancing vaccine-specific immunity. Although almost all vaccinations are given during infancy and childhood, the numbers of and results from studies using probiotics in pediatric subjects are limited. This review evaluates recent clinical trials of probiotics used to enhance vaccine-specific immune responses in adults and infants. We highlight meaningful results and the implications of these findings for designing translational and clinical studies that will evaluate the potential clinical role for probiotics. We conclude that the touted health claims of probiotics for use in children to augment immunity warrant further investigation. In order to achieve this goal, a consensus should be reached on common study designs that apply similar treatment timelines, compare well-characterised probiotic strains and monitor effective responses against different classes of vaccines.
Rapkin, Bruce D; Weiss, Elisa S; Lounsbury, David W; Thompson, Hayley S; Goodman, Robert M; Schechter, Clyde B; Merzel, Cheryl; Shelton, Rachel C; Blank, Arthur E; Erb-Downward, Jennifer; Williams, Abigail; Valera, Pamela; Padgett, Deborah K
2012-12-01
Dissemination efforts must optimize interventions for new settings and populations. As such, dissemination research should incorporate principles of quality improvement. Comprehensive Dynamic Trial (CDT) designs examine how information gained during dissemination may be used to modify interventions and improve performance. Although CDT may offer distinct advantages over static designs, organizing the many necessary roles and activities is a significant challenge. In this article, we discuss use of the Interactive Systems Framework for Dissemination and Implementation to systematically implement a CDT. Specifically, we describe "Bronx ACCESS", a program designed to disseminate evidence-based strategies to promote adherence to mammography guidelines. In Bronx ACCESS, the Intervention Delivery System will elicit information needed to adapt strategies to specific settings and circumstances. The Intervention Synthesis and Translation System will use this information to test changes to strategies through "embedded experiments". The Intervention Support System will build local capacities found to be necessary for intervention institutionalization. Simulation modeling will be used to integrate findings across systems. Results will inform on-going policy debate about interventions needed to promote population-level screening. More generally, this project is intended to advance understanding of research paradigms necessary to study dissemination.
[Economic analysis of multinational clinical trials in oncology].
Lejeune, Catherine; Lueza, Béranger; Bonastre, Julia
2018-02-01
In oncology, as in other fields of medicine, international multicentre clinical trials came into being so as to include a sufficient number of subjects to investigate a clinical situation. The existence of tight budgetary constraints and the desire to make the best use of the resources available have resulted in the development of economic evaluations associated with these trials, which, thanks to their level of evidence and their size, provide particularly relevant material. Nonetheless, economic evaluations alongside international clinical trials raise specific questions of methodology with regard to both the design and the analysis of the results. Indeed, the costs of goods and services consumed, the types and quantities of resources, and medical practices vary from one country to another and within an individual country. Economic data from the different countries involved must be available so as to study and to take into account this variability, and appropriate techniques for cost estimations and analysis must be implemented to aggregate the results from several countries. From a review of the literature, the aim of this work was to provide an overview of the specific methodological features of economic evaluations alongside international clinical trials: analysis of efficacy data from several countries, collection of resources and real costs, methods to establish the monetary value of resources, methods to aggregate results accounting for the trial effect. Copyright © 2017 Société Française du Cancer. Published by Elsevier Masson SAS. All rights reserved.
F.Kaminski, Michal; Bretthauer, Michael; Zauber, Ann G.; Kuipers, Ernst J.; Adami, Hans-Olov; van Ballegooijen, Marjolein; Regula, Jaroslaw; van Leerdam, Monique; Stefansson, Tryggvi; Påhlman, Lars; Dekker, Evelien; Hernán, Miguel A.; Garborg, Kjetil; Hoff, Geir
2017-01-01
Background While colonoscopy screening is widely used in several European countries and the United States, no randomised trials exist to quantify its benefits. The Nordic-European Initiative on Colorectal Cancer (NordICC) is a multinational, randomized controlled trial aiming at investigating the effect of colonoscopy screening on CRC incidence and mortality. This paper describes the rationale and design of the NordICC trial. Material and methods Men and women age 55 to 64 years are drawn from the population registries in the participating countries and randomly assigned to either once-only colonoscopy screening with removal of all detected lesions, or no screening (standard of care in the trial regions). All individuals are followed for 15 years after inclusion using dedicated national registries. Results The primary endpoints of the trial are cumulative CRC-specific death and CRC incidence during 15 years of follow up. We hypothesize a 50% CRC mortality-reducing efficacy of the colonoscopy intervention and predict 50% compliance, yielding a 25% mortality reduction among those invited to screening. For 90% power and a two-sided alpha level of 0.05, using a 2:1 randomisation, 45,600 individuals will be randomised to control, and 22,800 individuals to the colonoscopy group. Interim analyses of the effect of colonoscopy on CRC incidence and mortality will be performed at 10 years follow-up. Conclusions The aim of the NordICC trial is to quantify the effectiveness of population-based colonoscopy screening. This will allow development of evidence-based guidelines for CRC screening in the general population. PMID:22723185
Statistical power, the Belmont report, and the ethics of clinical trials.
Vollmer, Sara H; Howard, George
2010-12-01
Achieving a good clinical trial design increases the likelihood that a trial will take place as planned, including that data will be obtained from a sufficient number of participants, and the total number of participants will be the minimal required to gain the knowledge sought. A good trial design also increases the likelihood that the knowledge sought by the experiment will be forthcoming. Achieving such a design is more than good sense-it is ethically required in experiments when participants are at risk of harm. This paper argues that doing a power analysis effectively contributes to ensuring that a trial design is good. The ethical importance of good trial design has long been recognized for trials in which there is risk of serious harm to participants. However, whether the quality of a trial design, when the risk to participants is only minimal, is an ethical issue is rarely discussed. This paper argues that even in cases when the risk is minimal, the quality of the trial design is an ethical issue, and that this is reflected in the emphasis the Belmont Report places on the importance of the benefit of knowledge gained by society. The paper also argues that good trial design is required for true informed consent.
Using e-technologies in clinical trials
Rosa, Carmen; Campbell, Aimee N. C.; Miele, Gloria M.; Brunner, Meg; Winstanley, Erin L.
2015-01-01
Clinical trials have been slow to incorporate e-technology (digital and electronic technology that utilizes mobile devices or the Internet) into the design and execution of studies. In the meantime, individuals and corporations are relying more on electronic platforms and most have incorporated such technology into their daily lives. This paper provides a general overview of the use of e-technologies in clinical trials research, specifically within the last decade, marked by rapid growth of mobile and Internet-based tools. Benefits of and challenges to the use of e-technologies in data collection, recruitment and retention, delivery of interventions, and dissemination are provided, as well as a description of the current status of regulatory oversight of e-technologies in clinical trials research. As an example of ways in which e-technologies can be used for intervention delivery, a summary of e-technologies for treatment of substance use disorders is presented. Using e-technologies to design and implement clinical trials has the potential to reach a wide audience, making trials more efficient while also reducing costs; however, researchers should be cautious when adopting these tools given the many challenges in using new technologies, as well as threats to participant privacy/confidentiality. Challenges of using e-technologies can be overcome with careful planning, useful partnerships, and forethought. The role of web- and smartphone-based applications is expanding, and the increasing use of those platforms by scientists and the public alike make them tools that cannot be ignored. PMID:26176884
Using e-technologies in clinical trials.
Rosa, Carmen; Campbell, Aimee N C; Miele, Gloria M; Brunner, Meg; Winstanley, Erin L
2015-11-01
Clinical trials have been slow to incorporate e-technology (digital and electronic technology that utilizes mobile devices or the Internet) into the design and execution of studies. In the meantime, individuals and corporations are relying more on electronic platforms and most have incorporated such technology into their daily lives. This paper provides a general overview of the use of e-technologies in clinical trials research, specifically within the last decade, marked by rapid growth of mobile and Internet-based tools. Benefits of and challenges to the use of e-technologies in data collection, recruitment and retention, delivery of interventions, and dissemination are provided, as well as a description of the current status of regulatory oversight of e-technologies in clinical trials research. As an example of ways in which e-technologies can be used for intervention delivery, a summary of e-technologies for treatment of substance use disorders is presented. Using e-technologies to design and implement clinical trials has the potential to reach a wide audience, making trials more efficient while also reducing costs; however, researchers should be cautious when adopting these tools given the many challenges in using new technologies, as well as threats to participant privacy/confidentiality. Challenges of using e-technologies can be overcome with careful planning, useful partnerships, and forethought. The role of web- and smartphone-based applications is expanding, and the increasing use of those platforms by scientists and the public alike make them tools that cannot be ignored. Published by Elsevier Inc.
Critical Questions about PARADIGM-HF and the Future
Chen, Chen-Huan
2016-01-01
Cardiovascular (CV) diseases in general and heart failure (HF) in particular are major contributors to death and morbidity and are also recognized as important drivers of health care expenditure. The PARADIGM-HF trial was a pivotal trial designed to compare the long-term effects of LCZ696 with enalapril in patients with symptomatic HF with reduced ejection fraction (HFrEF). This review article presents an in-depth view of the PARADIGM-HF trial and the implications of the results in the management of patients with HF and is based on peer reviewed manuscripts, editorials, perspectives and opinions written about the PARADIGM-HF trial. The article presents the key safety and efficacy results of the trial with specific emphasis on the clinical implications of these findings. The review highlights the highly statistically significant, 20% reduction in the primary composite endpoint of cardiovascular death or HF hospitalization, and a 16% reduction in the risk of death from any cause. It also provides an overview of the design, clinical findings, limitations and special areas of clinical interest. The review discusses the future of LCZ696 and additional trials that seek to answer questions in other sub-populations of patients with HF. The article reiterates what has been concluded by many experts in the field of HF- the introduction of LCZ696 into routine clinical care, while dependent on the regulatory approvals in various countries as well as acceptance by physicians, payers and patients, will change the treatment landscape for patients with HFrEF. PMID:27471351
Mitry, Danny; Peto, Tunde; Hayat, Shabina; Morgan, James E; Khaw, Kay-Tee; Foster, Paul J
2013-01-01
Crowdsourcing is the process of outsourcing numerous tasks to many untrained individuals. Our aim was to assess the performance and repeatability of crowdsourcing for the classification of retinal fundus photography. One hundred retinal fundus photograph images with pre-determined disease criteria were selected by experts from a large cohort study. After reading brief instructions and an example classification, we requested that knowledge workers (KWs) from a crowdsourcing platform classified each image as normal or abnormal with grades of severity. Each image was classified 20 times by different KWs. Four study designs were examined to assess the effect of varying incentive and KW experience in classification accuracy. All study designs were conducted twice to examine repeatability. Performance was assessed by comparing the sensitivity, specificity and area under the receiver operating characteristic curve (AUC). Without restriction on eligible participants, two thousand classifications of 100 images were received in under 24 hours at minimal cost. In trial 1 all study designs had an AUC (95%CI) of 0.701(0.680-0.721) or greater for classification of normal/abnormal. In trial 1, the highest AUC (95%CI) for normal/abnormal classification was 0.757 (0.738-0.776) for KWs with moderate experience. Comparable results were observed in trial 2. In trial 1, between 64-86% of any abnormal image was correctly classified by over half of all KWs. In trial 2, this ranged between 74-97%. Sensitivity was ≥ 96% for normal versus severely abnormal detections across all trials. Sensitivity for normal versus mildly abnormal varied between 61-79% across trials. With minimal training, crowdsourcing represents an accurate, rapid and cost-effective method of retinal image analysis which demonstrates good repeatability. Larger studies with more comprehensive participant training are needed to explore the utility of this compelling technique in large scale medical image analysis.
Australasian Resuscitation In Sepsis Evaluation trial statistical analysis plan.
Delaney, Anthony; Peake, Sandra L; Bellomo, Rinaldo; Cameron, Peter; Holdgate, Anna; Howe, Belinda; Higgins, Alisa; Presneill, Jeffrey; Webb, Steve
2013-10-01
The Australasian Resuscitation In Sepsis Evaluation (ARISE) study is an international, multicentre, randomised, controlled trial designed to evaluate the effectiveness of early goal-directed therapy compared with standard care for patients presenting to the ED with severe sepsis. In keeping with current practice, and taking into considerations aspects of trial design and reporting specific to non-pharmacologic interventions, this document outlines the principles and methods for analysing and reporting the trial results. The document is prepared prior to completion of recruitment into the ARISE study, without knowledge of the results of the interim analysis conducted by the data safety and monitoring committee and prior to completion of the two related international studies. The statistical analysis plan was designed by the ARISE chief investigators, and reviewed and approved by the ARISE steering committee. The data collected by the research team as specified in the study protocol, and detailed in the study case report form were reviewed. Information related to baseline characteristics, characteristics of delivery of the trial interventions, details of resuscitation and other related therapies, and other relevant data are described with appropriate comparisons between groups. The primary, secondary and tertiary outcomes for the study are defined, with description of the planned statistical analyses. A statistical analysis plan was developed, along with a trial profile, mock-up tables and figures. A plan for presenting baseline characteristics, microbiological and antibiotic therapy, details of the interventions, processes of care and concomitant therapies, along with adverse events are described. The primary, secondary and tertiary outcomes are described along with identification of subgroups to be analysed. A statistical analysis plan for the ARISE study has been developed, and is available in the public domain, prior to the completion of recruitment into the study. This will minimise analytic bias and conforms to current best practice in conducting clinical trials. © 2013 Australasian College for Emergency Medicine and Australasian Society for Emergency Medicine.
George, Stephen L; Switzer, Boyd R; Snyder, Denise C; Madden, John F; Polascik, Thomas J; Ruffin, Mack T; Vollmer, Robin T
2008-01-01
Background The time between the diagnosis of cancer and a planned definitive surgical procedure offers a strong and direct approach for assessing the impact of interventions (including lifestyle interventions) on the biology of the target tissue and the tumor. Despite the many strengths of presurgical models, there are practical issues and challenges that arise when using this approach. Purpose/Methods We recently completed an NIH-funded phase II trial that utilized a presurgical model in testing the comparative effects of flaxseed supplementation and/or dietary fat restriction on the biology and biomarkers associated with prostatic carcinoma. Herein, we report the rationale for our original design, discuss modifications in strategy, and relay experiences in implementing this trial related to the following topics: (1) subject accrual; (2) subject retention; (3) intervention delivery; and (4) retrieval and completion rates regarding the collection of paraffin-embedded and fresh frozen prostate tissue, blood, urine, ejaculate, anthropometric measures and survey data. Results This trial achieved its accrual target, i.e., a racially-representative (70% white, 30% minority) sample of 161 participants, low rates of attrition (7%); and collection rates that exceeded 90% for almost all biospecimens and survey data. While the experience gained from pilot studies was invaluable in designing this trial, the complexity introduced by the collection of several biospecimens, inclusion of a team of pathologists (to provide validated readings), and shifts in practice patterns related to prostatectomy, made it necessary to revise our protocol; lessons from our experiences are offered within this article. Conclusions While our experience specifically relates to the implementation of a presurgical model-based trial in prostate cancer aimed at testing flaxseed-supplemented and fat-restricted diets, many of the lessons learned have broad application to trials that utilize a presurgical model or dietary modification within various cancer populations. PMID:18559416
Dahlberg, Suzanne E; Shapiro, Geoffrey I; Clark, Jeffrey W; Johnson, Bruce E
2014-07-01
Phase I trials have traditionally been designed to assess toxicity and establish phase II doses with dose-finding studies and expansion cohorts but are frequently exceeding the traditional sample size to further assess endpoints in specific patient subsets. The scientific objectives of phase I expansion cohorts and their evolving role in the current era of targeted therapies have yet to be systematically examined. Adult therapeutic phase I trials opened within Dana-Farber/Harvard Cancer Center (DF/HCC) from 1988 to 2012 were identified for sample size details. Statistical designs and study objectives of those submitted in 2011 were reviewed for expansion cohort details. Five hundred twenty-two adult therapeutic phase I trials were identified during the 25 years. The average sample size of a phase I study has increased from 33.8 patients to 73.1 patients over that time. The proportion of trials with planned enrollment of 50 or fewer patients dropped from 93.0% during the time period 1988 to 1992 to 46.0% between 2008 and 2012; at the same time, the proportion of trials enrolling 51 to 100 patients and more than 100 patients increased from 5.3% and 1.8%, respectively, to 40.5% and 13.5% (χ(2) test, two-sided P < .001). Sixteen of the 60 trials (26.7%) in 2011 enrolled patients to three or more sub-cohorts in the expansion phase. Sixty percent of studies provided no statistical justification of the sample size, although 91.7% of trials stated response as an objective. Our data suggest that phase I studies have dramatically changed in size and scientific scope within the last decade. Additional studies addressing the implications of this trend on research processes, ethical concerns, and resource burden are needed. © The Author 2014. Published by Oxford University Press. All rights reserved.
Phase II Trials for Heterogeneous Patient Populations with a Time-to-Event Endpoint.
Jung, Sin-Ho
2017-07-01
In this paper, we consider a single-arm phase II trial with a time-to-event end-point. We assume that the study population has multiple subpopulations with different prognosis, but the study treatment is expected to be similarly efficacious across the subpopulations. We review a stratified one-sample log-rank test and present its sample size calculation method under some practical design settings. Our sample size method requires specification of the prevalence of subpopulations. We observe that the power of the resulting sample size is not very sensitive to misspecification of the prevalence.
The role and potential contribution of clinical research nurses to clinical trials.
Spilsbury, Karen; Petherick, Emily; Cullum, Nicky; Nelson, Andrea; Nixon, Jane; Mason, Su
2008-02-01
This study explores the scope and potential contribution of the Clinical Research Nurse (CRN) role to clinical trials of a nursing-specific topic. Over the past two decades, there have been increases in the numbers of nurses working as CRNs because of the increasing global demand for clinical trials. CRNs can influence the quality of clinical trials but the scope and contribution of the role to clinical trials is not known. Qualitative focus group study. A focus group interview was carried out with CRNs (n = 9) employed on a large, multi-centre (six NHS Trusts) randomized controlled trial of pressure area care. The focus group interview was recorded, alongside field notes of participant interactions and behaviours, and transcribed verbatim. Data were analysed for thematic content and process. CRNs described their transition to a clinical research role. They reported a lack of confidence, role conflict as researcher and nurse, the challenges of gaining cooperation of clinical nursing staff to comply with trial protocols and difficulties maintaining their own motivation. CRNs provided their perceptions and observations of pressure area care and prevention. They identified areas of inadequate treatment, management and care, influenced by organizational and clinical aspects of care delivery. The study reveals challenges associated with training and management of CRNs. CRNs are usually associated with trial recruitment and data collection. This study highlights the additional contributions of CRNs for the study of topics specific to nursing as the result of their unique placement in the research centres as informal 'participant observers.' Such observations enhance understanding of the contexts being studied. These findings are relevant to the design and conduct of research studies of nursing care and practice and present ways for investigators to optimize the skills and knowledge of nurses working as CRNs.
Edwards, Tansy; Semple, Malcolm G; De Weggheleire, Anja; Claeys, Yves; De Crop, Maaike; Menten, Joris; Ravinetto, Raffaella; Temmerman, Sarah; Lynen, Lutgarde; Bah, Elhadj Ibrahima; Smith, Peter G; van Griensven, Johan
2016-02-01
The Ebola virus disease outbreak in 2014-2015 led to a huge caseload with a high case fatality rate. No specific treatments were available beyond supportive care for conditions such as dehydration and shock. Evaluation of treatment with convalescent plasma from Ebola survivors was identified as a priority. We evaluated this intervention in an emergency setting, where randomization was unacceptable. The original trial design was an open-label study comparing patients receiving convalescent plasma and supportive care to patients receiving supportive care alone. The comparison group comprised patients recruited at the start of the trial before convalescent plasma became available, as well as patients presenting during the trial for whom there was insufficient blood group-compatible plasma or no staffing capacity to provide additional transfusions. However, during the trial, convalescent plasma was available to treat all new patients. The design was changed to use a comparator group comprising patients previously treated at the same Ebola treatment center prior to the start of the trial. In the analysis, it was planned to adjust for any differences in prognostic variables between intervention and comparison groups, specifically baseline polymerase chain reaction cycle threshold and age. In addition, adjustment was planned for other potential confounders, identified in the analysis, such as patient presenting symptoms and time to treatment seeking. Because plasma treatment started up to 3 days after diagnosis and we could not define a similar time-point for the comparator group, patients who died before the third day after confirmation of diagnosis were excluded from both intervention and comparison groups in a per-protocol analysis. Some patients received additional experimental treatments soon after plasma treatment, and these were excluded. We also analyzed mortality including all patients from the time of confirmed diagnosis, irrespective of whether those in the trial series actually received plasma, as an intention-to-treat analysis. Per-protocol and intention-to-treat approaches gave similar conclusions. An important caveat in the interpretation of the findings is that it is unlikely that all potential sources of confounding, such as any variation in supportive care over time, were eliminated. Protocols and electronic data capture systems have now been extensively field-tested for emergency evaluation of treatment with convalescent plasma. Ongoing studies seek to quantify the level of neutralizing antibodies in different plasma donations to determine whether this influences the response and survival of treated patients. © The Author(s) 2016.
Franco, Silvia; Hoertel, Nicolas; McMahon, Kibby; Wang, Shuai; Rodríguez-Fernández, Jorge Mario; Peyre, Hugo; Limosin, Frédéric; Blanco, Carlos
2016-08-01
The present study sought to quantify the generalizability of pharmacologic and psychotherapy clinical trial results in individuals with a DSM-IV diagnosis of posttraumatic stress disorder (PTSD) to a large representative community sample. Data were derived from the 2004-2005 National Epidemiologic Survey on Alcohol and Related Conditions (NESARC), a large nationally representative sample of the adult US population. We applied a standard set of exclusion criteria representative of pharmacologic and psychotherapy clinical trials to all adults with a DSM-IV diagnosis of PTSD in the previous 12 months (n = 1,715) and then to a subsample of participants seeking treatment (n = 366). Our aim was to assess how many participants with PTSD would fulfill typical eligibility criteria. We found that more than 6 of 10 respondents from the overall PTSD sample and more than 7 of 10 respondents seeking treatment for PTSD would have been excluded by 1 exclusion criterion or more in a typical pharmacologic trial. In contrast, about 2 of 10 participants in the full sample and about 3 of 10 participants seeking treatment for PTSD would have been excluded in a typical psychotherapy efficacy trial. We found that psychotherapy trial results may be applied to most patients with PTSD in routine clinical practice. The designers of pharmacologic clinical trials should carefully consider the trade-offs between the application of each exclusion criterion and its impact on representativeness. Specification a priori of the goals of the study, better justification for each exclusion criterion, and estimation of the proportion of individuals ineligible for the trial would assist study design. Developing integrated forms of pharmacotherapy and psychotherapy that simultaneously target commonly overlapping psychiatric disorders may yield more informative results for mental health care providers and research funding agencies. © Copyright 2016 Physicians Postgraduate Press, Inc.
Fellrath, Jean-Marc; Kettner, Alexander; Dufour, Nathalie; Frigerio, Christian; Schneeberger, Dominique; Leimgruber, Annette; Corradin, Gampietro; Spertini, François
2003-04-01
There is a need to improve the safety and efficacy of allergen-specific immunotherapy. Long synthetic peptide-based immunotherapy was proven safe, immunogenic, and protective in preclinical trials. To evaluate the safety and immunogenicity of an allergen-derived long synthetic overlapping peptide (LSP) immunotherapy, we designed a double-blind, placebo-controlled phase I clinical trial in patients hypersensitive to bee venom. Patients from the active group were injected at day 0 with a mixture of 3 LSPs mapping the entire PLA2 molecule, a major bee venom allergen, in a dose-escalating protocol to a maintenance dose of 100 microg per peptide repeated at days 4, 7, 14, 42, and 70. The control group was injected with human albumin. Whereas specific T-cell proliferation in the peptide group increased up to day 14, a sharp decline was observed thereafter, ending in specific T-cell hyporesponsiveness at day 80. Serum-specific IgG4 response was enhanced, in contrast to anti-PLA2 IgE. Specific T-cell cytokine modulation was marked by increased IL-10 and IFN-gamma secretion. LSP injections were well tolerated in all patients except for mild, late allergic reactions in 2 patients at day 70. The results of this short-term study demonstrate that LSP-based allergen immunotherapy was safe and able to induce T(H)1-type immune deviation, allergen-specific IL-10 production, and T-cell hyporesponsiveness. LSPs, which offer the advantage of covering all possible T-cell epitopes for any HLA genotype, can be considered candidates for a novel and safe approach of specific immunotherapy.
Backhouse, Martin E
2002-01-01
A number of approaches to conducting economic evaluations could be adopted. However, some decision makers have a preference for wholly stochastic cost-effectiveness analyses, particularly if the sampled data are derived from randomised controlled trials (RCTs). Formal requirements for cost-effectiveness evidence have heightened concerns in the pharmaceutical industry that development costs and times might be increased if formal requirements increase the number, duration or costs of RCTs. Whether this proves to be the case or not will depend upon the timing, nature and extent of the cost-effectiveness evidence required. To illustrate how different requirements for wholly stochastic cost-effectiveness evidence could have a significant impact on two of the major determinants of new drug development costs and times, namely RCT sample size and study duration. Using data collected prospectively in a clinical evaluation, sample sizes were calculated for a number of hypothetical cost-effectiveness study design scenarios. The results were compared with a baseline clinical trial design. The sample sizes required for the cost-effectiveness study scenarios were mostly larger than those for the baseline clinical trial design. Circumstances can be such that a wholly stochastic cost-effectiveness analysis might not be a practical proposition even though its clinical counterpart is. In such situations, alternative research methodologies would be required. For wholly stochastic cost-effectiveness analyses, the importance of prior specification of the different components of study design is emphasised. However, it is doubtful whether all the information necessary for doing this will typically be available when product registration trials are being designed. Formal requirements for wholly stochastic cost-effectiveness evidence based on the standard frequentist paradigm have the potential to increase the size, duration and number of RCTs significantly and hence the costs and timelines associated with new product development. Moreover, it is possible to envisage situations where such an approach would be impossible to adopt. Clearly, further research is required into the issue of how to appraise the economic consequences of alternative economic evaluation research strategies.
Daykin, Anne; Selman, Lucy E; Cramer, Helen; McCann, Sharon; Shorter, Gillian W; Sydes, Matthew R; Gamble, Carrol; Macefield, Rhiannon; Lane, J Athene; Shaw, Alison
2017-12-22
The oversight and conduct of a randomised controlled trial involves several stakeholders, including a Trial Steering Committee (TSC), Trial Management Group (TMG), Data Monitoring Committee (DMC), funder and sponsor. We aimed to examine how the relationships between these stakeholders affect the trial oversight process and its rigour, to inform future revision of Good Clinical Practice guidelines. Using an ethnographic study design, we observed the oversight processes of eight trials and conducted semi-structured interviews with members of the trials' TSCs and TMGs, plus other relevant informants, including sponsors and funders of trials. Data were analysed thematically, and findings triangulated and integrated to give a multi-perspective account of current oversight practices in the UK. Eight TSC and six TMG meetings from eight trials were observed and audio-recorded, and 66 semi-structured interviews conducted with 52 purposively sampled key informants. Five themes are presented: (1) Collaboration within the TMG and role of the CTU; (2) Collaboration and conflict between oversight committees; (3) Priorities; (4) Communication between trial oversight groups and (5) Power and accountability. There was evidence of collaborative relationships, based on mutual respect, between CTUs, TMGs and TSCs, but also evidence of conflict. Relationships between trial oversight committees were influenced by stakeholders' priorities, both organisational and individual. Good communication following specific, recognised routes played a central role in ensuring that relationships were productive and trial oversight efficient. Participants described the possession of power over trials as a shifting political landscape, and there was lack of clarity regarding the roles and accountability of each committee, the sponsor and funder. Stakeholders' perceptions of their own power over a trial, and the power of others, influenced relationships between those involved in trial oversight. Recent developments in trial design and conduct have been accompanied by changes in roles and relationships between trial oversight groups. Recognising and respecting the value of differing priorities among those involved in running trials is key to successful relationships between committees, funders and sponsors. Clarity regarding appropriate lines of communication, roles and accountability is needed. We present 10 evidence-based recommendations to inform updates to international trial guidance, particularly the Medical Research Council guidelines.
Bibby, Anna C; Torgerson, David J; Leach, Samantha; Lewis-White, Helen; Maskell, Nick A
2018-01-08
The 'trials within cohorts' (TwiC) design is a pragmatic approach to randomised trials in which trial participants are randomly selected from an existing cohort. The design has multiple potential benefits, including the option of conducting multiple trials within the same cohort. To date, the TwiC design methodology been used in numerous clinical settings but has never been applied to a clinical trial of an investigational medicinal product (CTIMP). We have recently secured the necessary approvals to undertake the first CTIMP using the TwiC design. In this paper, we describe some of the considerations and modifications required to ensure such a trial is compliant with Good Clinical Practice and international clinical trials regulations. We advocate using a two-stage consent process and using the consent stages to explicitly differentiate between trial participants and cohort participants who are providing control data. This distinction ensured compliance but had consequences with respect to costings, recruitment and the trial assessment schedule. We have demonstrated that it is possible to secure ethical and regulatory approval for a CTIMP TwiC. By including certain considerations at the trial design stage, we believe this pragmatic and efficient methodology could be utilised in other CTIMPs in future.
Moore, Sophie E; Fulford, Anthony Jc; Darboe, Momodou K; Jobarteh, Modou Lamin; Jarjou, Landing M; Prentice, Andrew M
2012-10-11
Recent observational research indicates that immune development may be programmed by nutritional exposures early in life. Such findings require replication from trials specifically designed to assess the impact of nutritional intervention during pregnancy on infant immune development. The current trial seeks to establish: (a) which combination of protein-energy (PE) and multiple-micronutrient (MMN) supplements would be most effective; and (b) the most critical periods for intervention in pregnancy and infancy, for optimal immune development in infancy. The ENID Trial is a 2 x 2 x 2 factorial randomized, partially blind trial to assess whether nutritional supplementation to pregnant women (from < 20 weeks gestation to term) and their infants (from 6 to 12 months of age) can enhance infant immune development. Eligible pregnant women from the West Kiang region of The Gambia (pregnancy dated by ultrasound examination) are randomized on entry to 4 intervention groups (Iron-folate (FeFol = standard care), multiple micronutrients (MMN), protein-energy (PE), PE + MMN). Women are visited at home weekly for supplement administration and morbidity assessment and seen at MRC Keneba at 20 and 30 weeks gestation for a detailed antenatal examination, including ultrasound. At delivery, cord blood and placental samples are collected, with detailed infant anthropometry collected within 72 hours. Infants are visited weekly thereafter for a morbidity questionnaire. From 6 to 12 months of age, infants are further randomized to a lipid-based nutritional supplement, with or without additional MMN. The primary outcome measures of this study are thymic development during infancy, and antibody response to vaccination. Measures of cellular markers of immunity will be made in a selected sub-cohort. Subsidiary studies to the main trial will additionally assess the impact of supplementation on infant growth and development to 24 months of age. The proposed trial is designed to test whether nutritional repletion can enhance early immune development and, if so, to help determine the most efficacious form of nutritional support. Where there is evidence of benefit from a specific intervention/combination of interventions, future research should focus on refining the supplements to achieve the optimal, most cost-effective balance of interventions for improved health outcomes.
Arnup, Sarah J; McKenzie, Joanne E; Hemming, Karla; Pilcher, David; Forbes, Andrew B
2017-08-15
In a cluster randomised crossover (CRXO) design, a sequence of interventions is assigned to a group, or 'cluster' of individuals. Each cluster receives each intervention in a separate period of time, forming 'cluster-periods'. Sample size calculations for CRXO trials need to account for both the cluster randomisation and crossover aspects of the design. Formulae are available for the two-period, two-intervention, cross-sectional CRXO design, however implementation of these formulae is known to be suboptimal. The aims of this tutorial are to illustrate the intuition behind the design; and provide guidance on performing sample size calculations. Graphical illustrations are used to describe the effect of the cluster randomisation and crossover aspects of the design on the correlation between individual responses in a CRXO trial. Sample size calculations for binary and continuous outcomes are illustrated using parameters estimated from the Australia and New Zealand Intensive Care Society - Adult Patient Database (ANZICS-APD) for patient mortality and length(s) of stay (LOS). The similarity between individual responses in a CRXO trial can be understood in terms of three components of variation: variation in cluster mean response; variation in the cluster-period mean response; and variation between individual responses within a cluster-period; or equivalently in terms of the correlation between individual responses in the same cluster-period (within-cluster within-period correlation, WPC), and between individual responses in the same cluster, but in different periods (within-cluster between-period correlation, BPC). The BPC lies between zero and the WPC. When the WPC and BPC are equal the precision gained by crossover aspect of the CRXO design equals the precision lost by cluster randomisation. When the BPC is zero there is no advantage in a CRXO over a parallel-group cluster randomised trial. Sample size calculations illustrate that small changes in the specification of the WPC or BPC can increase the required number of clusters. By illustrating how the parameters required for sample size calculations arise from the CRXO design and by providing guidance on both how to choose values for the parameters and perform the sample size calculations, the implementation of the sample size formulae for CRXO trials may improve.
Improving the Management Style of School Principals: Results from a Randomized Trial
ERIC Educational Resources Information Center
Lassibille, Gérard
2016-01-01
Using information from a randomized experiment carried out over the course of two school years in Madagascar, this paper evaluates the impact of specific actions designed to streamline and tighten the work processes of public primary school directors. The results show that interventions at the school level, reinforced by interventions at the…
Revealing List-Level Control in the Stroop Task by Uncovering Its Benefits and a Cost
Bugg, Julie M.; McDaniel, Mark A.; Scullin, Michael K.; Braver, Todd S.
2012-01-01
Interference is reduced in mostly incongruent relative to mostly congruent lists. Classic accounts of this list-wide proportion congruence effect assume that list-level control processes strategically modulate word reading. Contemporary accounts posit that reliance on the word is modulated poststimulus onset by item-specific information (e.g., proportion congruency of the word). To adjudicate between these accounts, we used novel designs featuring neutral trials. In two experiments, we showed that the list-wide proportion congruence effect is accompanied by a change in neutral trial color-naming performance. Because neutral words have no item-specific bias, this pattern can be attributed to list-level control. Additionally, we showed that list-level attenuation of word reading led to a cost to performance on a secondary prospective memory task but only when that task required processing of the irrelevant, neutral word. These findings indicate that the list-wide proportion congruence effect at least partially reflects list-level control and challenge purely item-specific accounts of this effect. PMID:21767049
Viksveen, Petter; Relton, Clare; Nicholl, Jon
2017-07-06
Trials which test the effectiveness of interventions compared with the status quo frequently encounter challenges. The cohort multiple randomised controlled trial (cmRCT) design is an innovative approach to the design and conduct of pragmatic trials which seeks to address some of these challenges. In this article, we report our experiences with the first completed randomised controlled trial (RCT) using the cmRCT design. This trial-the Depression in South Yorkshire (DEPSY) trial-involved comparison of treatment as usual (TAU) with TAU plus the offer of an intervention for people with self-reported long-term moderate to severe depression. In the trial, we used an existing large population-based cohort: the Yorkshire Health Study. We discuss our experiences with recruitment, attrition, crossover, data analysis, generalisability of results, and cost. The main challenges in using the cmRCT design were the high crossover to the control group and the lower questionnaire response rate among patients who refused the offer of treatment. However, the design did help facilitate efficient and complete recruitment of the trial population as well as analysable data that were generalisable to the population of interest. Attrition rates were also smaller than those reported in other depression trials. This first completed full trial using the cmRCT design testing an intervention for self-reported depression was associated with a number of important benefits. Further research is required to compare the acceptability and cost effectiveness of standard pragmatic RCT design with the cmRCT design. ISRCTN registry: ISRCTN02484593 . Registered on 7 Jan 2013.
The Design of Clinical Trials in Portal Hypertension.
Abraldes, Juan G; Garcia-Tsao, Guadalupe
2017-02-01
Portal hypertension (PH) is the main consequence of cirrhosis and is responsible for the majority of its complications. Gastroesophageal varices and variceal hemorrhage are direct consequences of PH; therefore, most clinical trials in PH have been directed toward treating or preventing variceal hemorrhage. However, varices and variceal hemorrhage are not isolated events; they must be considered in the context of the presence (or absence) of other complications of cirrhosis/PH. Cirrhosis progresses across different stages, each with a different prognosis and pathophysiology and hence different therapeutic targets. In this review, the authors discuss the design of proof-of-concept studies for the assessment of new drugs for the treatment of PH, that are mainly based on the drug's ability to reduce the hepatic venous pressure gradient. They further discuss the design of studies with clinical endpoints in the context of each stage of cirrhosis, specifically targets of therapy, optimal therapies in the control arm, risk stratification, and primary outcome. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.
Das, Abhik; Tyson, Jon; Pedroza, Claudia; Schmidt, Barbara; Gantz, Marie; Wallace, Dennis; Truog, William E; Higgins, Rosemary D
2016-10-01
Impressive advances in neonatology have occurred over the 30 years of life of The Eunice Kennedy Shriver National Institute of Child Health and Human Development Neonatal Research Network (NRN). However, substantial room for improvement remains in investigating and further developing the evidence base for improving outcomes among the extremely premature. We discuss some of the specific methodological challenges in the statistical design and analysis of randomized trials and observational studies in this population. Challenges faced by the NRN include designing trials for unusual or rare outcomes, accounting for and explaining center variations, identifying other subgroup differences, and balancing safety and efficacy concerns between short-term hospital outcomes and longer-term neurodevelopmental outcomes. In conclusion, the constellation of unique patient characteristics in neonates calls for broad understanding and careful consideration of the issues identified in this article for conducting rigorous studies in this population. Copyright © 2016 Elsevier Inc. All rights reserved.
Immunotherapy for B-Cell Neoplasms using T Cells expressing Chimeric Antigen Receptors
Boulassel, Mohamed-Rachid; Galal, Ahmed
2012-01-01
Immunotherapy with T cells expressing chimeric antigen receptors (CAR) is being evaluated as a potential treatment for B-cell neoplasms. In recent clinical trials it has shown promising results. As the number of potential candidate antigens expands, the choice of suitable target antigens becomes more challenging to design studies and to assess optimal efficacy of CAR. Careful evaluation of candidate target antigens is required to ensure that T cells expressing CAR will preferentially kill malignant cells with a minimal toxicity against normal tissues. B cells express specific surface antigens that can theoretically act as targets for CAR design. Although many of these antigens can stimulate effective cellular immune responses in vivo, their implementation in clinical settings remains a challenge. Only targeted B-cell antigens CD19 and CD20 have been tested in clinical trials. This article reviews exploitable B cell surface antigens for CAR design and examines obstacles that could interfere with the identification of potentially useful cellular targets. PMID:23269948
Murray, Elizabeth; McAdam, Rodney
2007-01-01
This article compares and contrasts the main quality standards in the highly regulated pharmaceutical industry with specific focus on Good Clinical Practice (GCP), the standard for designing, conducting, recording and reporting clinical trials involving human participants. Comparison is made to ISO quality standards, which can be applied to all industries and types of organisation. The study is then narrowed to that of contract research organisations (CROs) involved in the conduct of clinical trials. The paper concludes that the ISO 9000 series of quality standards can act as a company-wide framework for quality management within such organisations by helping to direct quality efforts on a long-term basis without any loss of compliance. This study is valuable because comparative analysis in this domain is uncommon.
Clinical trials in pediatric neuro-oncology: what is missing and how we can improve.
Byer, Lennox; Kline, Cassie; Mueller, Sabine
2016-10-01
Brain tumors are the most common solid tumor in childhood, yet outcomes vary dramatically. High-grade gliomas have dismal outcomes with poor survival. By contrast, low-grade gliomas, have high survival rates, but children suffer from morbidity of tumor burden and therapy-associated side effects. In this article, we discuss how current trial designs often miss the opportunity to include end points beyond tumor response and thus fail to offer complete assessments of therapeutic approaches. Quality of life, neurocognitive function and neurofunctional deficits need to be considered when assessing overall success of a therapy. Herein, we identify specific end points that should be included in the interpretation of clinical trial results and accordingly, offer a more comprehensive approach to treatment decision-making.
The interaction between equipoise and logistics in clinical trials: A case study.
Warshaw, Meredith G; Carey, Vincent J; McFarland, Elizabeth J; Dawson, Liza; Abrams, Elaine; Melvin, Ann; Fairlie, Lee; Spiegel, Hans; Jay, Jonathan; Agwu, Allison L
2017-06-01
Equipoise is usually discussed as an ethical issue in clinical trials. However, it also has practical implications. Clinical equipoise is usually construed to mean uncertainty or disagreement among the expert clinician community. However, an individual physician's sense of equipoise may vary by location, based on the local standard of care or availability of specific treatment options, and these differences can affect providers' willingness to enroll participants into clinical trials. There are also logistical barriers to enrollment in international trials due to prolonged timelines for approvals by government agencies and ethical review boards. A multinational clinical trial of bridging strategies for treatment of non-adherent HIV-infected youth, experienced differing perceptions of equipoise due to disparities in availability of treatment options by country. Unfortunately, the countries with most demand for the trial were those where the approval process was most delayed, and the study was closed early due to slow accrual. When planning multicenter clinical trials, it is important to take into account heterogeneity among research sites and try to anticipate differences in equipoise and logistical factors between sites, in order to plan to address these issues at the design stage.
Yeterian, Julie D; Berke, Danielle S; Litz, Brett T
2017-10-01
Posttraumatic stress disorder (PTSD) from warzone exposure is associated with chronic and disabling social and occupational problems. However, functional impairment is rarely assessed or targeted directly in PTSD treatments, which instead focus on symptom reduction. Trauma-related contributors to diminished functioning, including guilt, shame, and anger resulting from morally compromising or loss-based war experiences, are also underemphasized. The goal of this clinical trial is to fill a substantial gap in the treatment of military-related PTSD by testing a modified Adaptive Disclosure (AD) therapy for war-related PTSD stemming from moral injury and traumatic loss focused on improving psychosocial functioning AD. This paper describes the rationale and design of a multi-site randomized controlled trial comparing AD to Present-Centered Therapy (PCT). We will recruit 186 veterans with PTSD, who will be assessed at baseline, post-treatment, and 3- and 6-months post-treatment. Primary outcomes are functional changes (i.e., functioning/disability and quality of life). Secondary outcomes are mental health variables (i.e., PTSD, depression, guilt, shame). We hypothesize that veterans treated with AD will experience greater improvements in all outcomes compared to those treated with PCT. This trial will advance knowledge in rehabilitation research by testing the first therapy specifically designed to address psychosocial functioning among veterans with war-related PTSD. The results may improve the quality of mental health care for veterans by offering an ecologically sound treatment for experiences that are uniquely impactful for war veterans. Published by Elsevier Inc.
Examining clinical supervision as a mechanism for changes in practice: a research protocol.
Dilworth, Sophie; Higgins, Isabel; Parker, Vicki; Kelly, Brian; Turner, Jane
2014-02-01
This paper describes the research protocol for a study exploring if and how clinical supervision facilitates change in practice relating to psychosocial aspects of care for Health Professionals, who have been trained to deliver a psychosocial intervention to adults with cancer. There is a recognized need to implement care that is in line with clinical practice guidelines for the psychosocial care of adults with cancer. Clinical supervision is recommended as a means to support Health Professionals in providing the recommended psychosocial care. A qualitative design embedded within an experimental, stepped wedge randomized control trial. The study will use discourse analysis to analyse audio-recorded data collected in clinical supervision sessions that are being delivered as one element of a large randomized control trial. The sessions will be attended primarily by nurses, but including physiotherapists, radiation therapists, occupational therapists. The Health Professionals are participants in a randomized control trial designed to reduce anxiety and depression of distressed adults with cancer. The sessions will be facilitated by psychiatrists experienced in psycho-oncology and the provision of clinical supervision. The proposed research is designed specifically to facilitate exploration of the mechanisms by which clinical supervision enables Health Professionals to deliver a brief, tailored psychosocial intervention in the context of their everyday practice. This is the first study to use discourse analysis embedded within an experimental randomized control trial to explore the mechanisms of change generated within clinical supervision by analysing the discourse within the clinical supervision sessions. © 2013 John Wiley & Sons Ltd.
Duru, Firat; Dorian, Paul; Favale, Stefano; Perings, Christian; Pedersen, Susanne S; Willems, Vincent
2010-05-01
Implantable cardioverter defibrillators (ICD) can prevent sudden cardiac death by delivering high-energy shocks in patients at risk of life-threatening ventricular tachyarrhythmias. Patients may be anxious about receiving inappropriate shocks in case of device or lead system malfunction, or about failing to receive needed therapy for the same reason. New devices include programmable vibrating patient notifiers (PN), which, by warning patients of a possible device dysfunction, might lower device-related anxiety. PAtient NOtifier feature for Reduction of Anxiety: a Multicentre ICD study (PANORAMIC) is a multicentre, randomized, clinical trial designed to examine the effects of the awareness of an active vibrating alert system on device-related anxiety. The trial will randomly assign 356 patients in a 1:1 design to a control group (PN OFF) vs. a treatment group (PN ON). Patients will be followed for 12 months, with visits scheduled at 6 and 12 months. During clinical follow-up visits, the ICD will be interrogated, and all patients will complete the Hospital Anxiety and Depression Scale and a device-related anxiety questionnaire. The sensitivity and specificity of PN, the effect of personality on anxiety, using the Type D scale (DS14), the number of delivered appropriate and inappropriate ICD therapies, changes in anxiety related to the delivery of appropriate or inappropriate shocks, crossovers from the assigned group, the number of hospitalizations, and the mortality rate will also be assessed. ClinicalTrials.gov Identifier: NCT00559559.
Pressure ulcer prevention in patients with advanced illness.
White-Chu, E Foy; Reddy, Madhuri
2013-03-01
Pressure ulcers can be challenging to prevent, particularly in patients with advanced illnesses. This review summarizes the relevant literature since 2011. Through a MEDLINE and CINAHL database search from January 1, 2011 to June 1, 2012, a total of 14 abstracts were found addressing the prevention of pressure ulcers in persons with advanced illness. Search terms included pressure ulcer, prevention, and control. Advanced illness was defined as patients transitioning from curative to supportive and palliative care. Ten original studies and four review articles specifically addressed pressure ulcer prevention. There were four articles that specifically addressed patients with advanced illness. The studies varied in quality. One systematic review, one randomized controlled trial, three prospective trials, two retrospective trials, one cost-effectiveness analysis, one quality improvement project, one comparative descriptive design, and four review articles were found. The interventions for pressure ulcer prevention were risk assessment, repositioning, surface selection, nutritional support and maintenance of skin integrity with or without incontinence. The quality of pressure ulcer prevention studies in persons with advanced illness is poor. Increased number and higher quality studies are needed to further investigate this important topic for these fragile patients.
Wattchow, Kimberley A; McDonnell, Michelle N; Hillier, Susan L
2018-02-01
To investigate the therapeutic interventions reported in the research literature and synthesize their effectiveness in improving upper limb (UL) function in the first 4 weeks poststroke. Electronic databases and trial registries were searched from inception until June 2016, in addition to searching systematic reviews by hand. Randomized controlled trials (RCTs), controlled trials, and interventional studies with pre/posttest design were included for adults within 4 weeks of any type of stroke with UL impairment. Participants all received an intervention of any physiotherapeutic or occupational therapeutic technique designed to address impairment or activity of the affected UL, which could be compared with usual care, sham, or another technique. Two reviewers independently assessed eligibility of full texts, and methodological quality of included studies was assessed using the Cochrane Risk of Bias Tool. A total of 104 trials (83 RCTs, 21 nonrandomized studies) were included (N=5225 participants). Meta-analyses of RCTs only (20 comparisons) and narrative syntheses were completed. Key findings included significant positive effects for modified constraint-induced movement therapy (mCIMT) (standardized mean difference [SMD]=1.09; 95% confidence interval [CI], .21-1.97) and task-specific training (SMD=.37; 95% CI, .05-.68). Evidence was found to support supplementary use of biofeedback and electrical stimulation. Use of Bobath therapy was not supported. Use of mCIMT and task-specific training was supported, as was supplementary use of biofeedback and electrical simulation, within the acute phase poststroke. Further high-quality studies into the initial 4 weeks poststroke are needed to determine therapies for targeted functional UL outcomes. Copyright © 2017 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.
French, Simon D; Green, Sally E; Francis, Jill J; Buchbinder, Rachelle; O'Connor, Denise A; Grimshaw, Jeremy M; Michie, Susan
2015-01-01
Objectives Implementation intervention effects can only be fully realised and understood if they are faithfully delivered. However the evaluation of implementation intervention fidelity is not commonly undertaken. The IMPLEMENT intervention was designed to improve the management of low back pain by general medical practitioners. It consisted of a two-session interactive workshop, including didactic presentations and small group discussions by trained facilitators. This study aimed to evaluate the fidelity of the IMPLEMENT intervention by assessing: (1) observed facilitator adherence to planned behaviour change techniques (BCTs); (2) comparison of observed and self-reported adherence to planned BCTs and (3) variation across different facilitators and different BCTs. Design The study compared planned and actual, and observed versus self-assessed delivery of BCTs during the IMPLEMENT workshops. Method Workshop sessions were audiorecorded and transcribed verbatim. Observed adherence of facilitators to the planned intervention was assessed by analysing the workshop transcripts in terms of BCTs delivered. Self-reported adherence was measured using a checklist completed at the end of each workshop session and was compared with the ‘gold standard’ of observed adherence using sensitivity and specificity analyses. Results The overall observed adherence to planned BCTs was 79%, representing moderate-to-high intervention fidelity. There was no significant difference in adherence to BCTs between the facilitators. Sensitivity of self-reported adherence was 95% (95% CI 88 to 98) and specificity was 30% (95% CI 11 to 60). Conclusions The findings suggest that the IMPLEMENT intervention was delivered with high levels of adherence to the planned intervention protocol. Trial registration number The IMPLEMENT trial was registered in the Australian New Zealand Clinical Trials Registry, ACTRN012606000098538 (http://www.anzctr.org.au/trial_view.aspx?ID=1162). PMID:26155819
Saper, Robert; Vinjamury, Sivarama; Elder, Charles
2013-01-01
Focus Area: Integrative Approaches to Care The panel discussants will present on the outcomes of four recent pragmatic trials covering the spectrum of Ayurvedic medicine, yoga, and meditation as therapeutic approaches for both acute and chronic conditions. The presenters will discuss: (1) a pilot study of a whole-systems Ayurveda and Yoga Therapy intervention for obesity; (2) a comparative effectiveness randomized controlled trial of hatha yoga, physical therapy, and education for non-specific chronic low back pain in low-income minority populations; (3) an investigation of the therapeutic usefulness of Shirodhara (Ayurvedic oil dripping therapy) as a treatment for insomnia; and (4) a discussion of the evidence base supporting implementation of meditation interventions in schools and workplace settings. Discussants will present information on study designs, research methodology, and outcome measure selection to highlight special considerations in conducting research on whole medical systems that use multi-target therapies and focus on patient-centered outcomes. Ayurvedic medicine and yoga are characterized by low-cost, noninvasive interventions that can be usefully offered as part of an integrative medicine therapeutic approach.
Burns, Karen E A; Devlin, John W; Hill, Nicholas S
2017-10-01
The call for meaningful patient and family engagement in research has recently gained considerable momentum. This article defines patient and family engagement broadly and specifically in clinical research. Using a multicenter, North American weaning trial as an exemplar, we describe our early experiences as clinical researchers with patient and family engagement. The role of our Patient and Family Advisory Committee in trial design and implementation is illustrated. Through our experiences, we share our insights regarding the perceived opportunities and also highlight some challenges associated with engaging patients and family engagement in critical care research. Although "engagement science" is in its infancy, engaging patients and families in research holds promise as a novel research paradigm that will not only provide new insights into the questions, methods, and outcomes used in ICU research, but it will also make investments in research more accountable and ensure a strong "patient- and family-centered focus" of our research. Copyright © 2017 American College of Chest Physicians. Published by Elsevier Inc. All rights reserved.
Adaptive designs in clinical trials: why use them, and how to run and report them.
Pallmann, Philip; Bedding, Alun W; Choodari-Oskooei, Babak; Dimairo, Munyaradzi; Flight, Laura; Hampson, Lisa V; Holmes, Jane; Mander, Adrian P; Odondi, Lang'o; Sydes, Matthew R; Villar, Sofía S; Wason, James M S; Weir, Christopher J; Wheeler, Graham M; Yap, Christina; Jaki, Thomas
2018-02-28
Adaptive designs can make clinical trials more flexible by utilising results accumulating in the trial to modify the trial's course in accordance with pre-specified rules. Trials with an adaptive design are often more efficient, informative and ethical than trials with a traditional fixed design since they often make better use of resources such as time and money, and might require fewer participants. Adaptive designs can be applied across all phases of clinical research, from early-phase dose escalation to confirmatory trials. The pace of the uptake of adaptive designs in clinical research, however, has remained well behind that of the statistical literature introducing new methods and highlighting their potential advantages. We speculate that one factor contributing to this is that the full range of adaptations available to trial designs, as well as their goals, advantages and limitations, remains unfamiliar to many parts of the clinical community. Additionally, the term adaptive design has been misleadingly used as an all-encompassing label to refer to certain methods that could be deemed controversial or that have been inadequately implemented.We believe that even if the planning and analysis of a trial is undertaken by an expert statistician, it is essential that the investigators understand the implications of using an adaptive design, for example, what the practical challenges are, what can (and cannot) be inferred from the results of such a trial, and how to report and communicate the results. This tutorial paper provides guidance on key aspects of adaptive designs that are relevant to clinical triallists. We explain the basic rationale behind adaptive designs, clarify ambiguous terminology and summarise the utility and pitfalls of adaptive designs. We discuss practical aspects around funding, ethical approval, treatment supply and communication with stakeholders and trial participants. Our focus, however, is on the interpretation and reporting of results from adaptive design trials, which we consider vital for anyone involved in medical research. We emphasise the general principles of transparency and reproducibility and suggest how best to put them into practice.
Methodology Series Module 4: Clinical Trials.
Setia, Maninder Singh
2016-01-01
In a clinical trial, study participants are (usually) divided into two groups. One group is then given the intervention and the other group is not given the intervention (or may be given some existing standard of care). We compare the outcomes in these groups and assess the role of intervention. Some of the trial designs are (1) parallel study design, (2) cross-over design, (3) factorial design, and (4) withdrawal group design. The trials can also be classified according to the stage of the trial (Phase I, II, III, and IV) or the nature of the trial (efficacy vs. effectiveness trials, superiority vs. equivalence trials). Randomization is one of the procedures by which we allocate different interventions to the groups. It ensures that all the included participants have a specified probability of being allocated to either of the groups in the intervention study. If participants and the investigator know about the allocation of the intervention, then it is called an "open trial." However, many of the trials are not open - they are blinded. Blinding is useful to minimize bias in clinical trials. The researcher should familiarize themselves with the CONSORT statement and the appropriate Clinical Trials Registry of India.
Methodology Series Module 4: Clinical Trials
Setia, Maninder Singh
2016-01-01
In a clinical trial, study participants are (usually) divided into two groups. One group is then given the intervention and the other group is not given the intervention (or may be given some existing standard of care). We compare the outcomes in these groups and assess the role of intervention. Some of the trial designs are (1) parallel study design, (2) cross-over design, (3) factorial design, and (4) withdrawal group design. The trials can also be classified according to the stage of the trial (Phase I, II, III, and IV) or the nature of the trial (efficacy vs. effectiveness trials, superiority vs. equivalence trials). Randomization is one of the procedures by which we allocate different interventions to the groups. It ensures that all the included participants have a specified probability of being allocated to either of the groups in the intervention study. If participants and the investigator know about the allocation of the intervention, then it is called an “open trial.” However, many of the trials are not open – they are blinded. Blinding is useful to minimize bias in clinical trials. The researcher should familiarize themselves with the CONSORT statement and the appropriate Clinical Trials Registry of India. PMID:27512184
Psychological therapies for thalassaemia.
Anie, Kofi A; Massaglia, Pia
2014-03-06
Thalassaemia is a group of genetic blood disorders characterised by the absence or reduction in the production of haemoglobin. Severity is variable from less severe anaemia, through thalassaemia intermedia, to profound severe anaemia (thalassaemia major). In thalassaemia major other complications include growth retardation, bone deformation, and enlarged spleen. Blood transfusion is required to treat severe forms of thalassaemia, but this results in excessive accumulation of iron in the body (iron overload), removed mostly by a drug called desferrioxamine through 'chelation therapy'. Non-routine treatments are bone marrow transplantation (which is age restricted), and possibly hydroxyurea, designed to raise foetal haemoglobin level, thus reducing anaemia. In addition, psychological therapies seem appropriate to improving outcome and adherence to medical treatment. To examine the evidence that in people with thalassaemia, psychological treatments improve the ability to cope with the condition, and improve both medical and psychosocial outcomes. We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group Haemoglobinopathies Trials Register which comprises of references identified from comprehensive electronic database searches and handsearches of relevant journals and abstract books of conference proceedings. Searches on the Internet were also performed.Date of the most recent search of the Group's Haemoglobinopathies Trials Register: 11 November 2013. All randomised or quasi-randomised controlled trials comparing the use of psychological intervention to no (psychological) intervention in people with thalassaemia. No trials of psychological therapies have been found in the literature for inclusion in this review. There are currently no results to be reported. As a chronic disease with a considerable role for self-management, psychological support seems appropriate for managing thalassaemia. However, from the information currently available, no conclusions can be made about the use of specific psychological therapies in thalassaemia. This systematic review has clearly identified the need for well-designed, adequately-powered, multicentre, randomised controlled trials assessing the effectiveness of specific psychological interventions for thalassaemia.
Toward a patient-specific tissue engineered vascular graft
Best, Cameron; Strouse, Robert; Hor, Kan; Pepper, Victoria; Tipton, Amy; Kelly, John; Shinoka, Toshiharu; Breuer, Christopher
2018-01-01
Integrating three-dimensional printing with the creation of tissue-engineered vascular grafts could provide a readily available, patient-specific, autologous tissue source that could significantly improve outcomes in newborns with congenital heart disease. Here, we present the recent case of a candidate for our tissue-engineered vascular graft clinical trial deemed ineligible due to complex anatomical requirements and consider the application of three-dimensional printing technologies for a patient-specific graft. We 3D-printed a closed-disposable seeding device and validated that it performed equivalently to the traditional open seeding technique using ovine bone marrow–derived mononuclear cells. Next, our candidate’s preoperative imaging was reviewed to propose a patient-specific graft. A seeding apparatus was then designed to accommodate the custom graft and 3D-printed on a commodity fused deposition modeler. This exploratory feasibility study represents an important proof of concept advancing progress toward a rationally designed patient-specific tissue-engineered vascular graft for clinical application. PMID:29568478
Greenberg, Rachel G; Corneli, Amy; Bradley, John; Farley, John; Jafri, Hasan S; Lin, Li; Nambiar, Sumathi; Noel, Gary J; Wheeler, Chris; Tiernan, Rosemary; Smith, P Brian; Roberts, Jamie; Benjamin, Daniel K
2018-03-01
Despite legislation to stimulate pediatric drug development through clinical trials, enrolling children in trials continues to be challenging. Non-investigator (those who have never served as a clinical trial investigator) providers are essential to recruitment of pediatric patients, but little is known regarding the specific barriers that limit pediatric providers from participating in and referring their patients to clinical trials. We conducted an online survey of pediatric providers from a wide variety of practice types across the United States to evaluate their attitudes and awareness of pediatric clinical trials. Using a 4-point Likert scale, providers described their perception of potential barriers to their practice serving as a site for pediatric clinical trials. Of the 136 providers surveyed, 52/136 (38%) had previously referred a pediatric patient to a trial, and only 17/136 (12%) had ever been an investigator for a pediatric trial. Lack of awareness of existing pediatric trials was a major barrier to patient referral by providers, in addition to consideration of trial risks, distance to the site, and time needed to discuss trial participation with parents. Overall, providers perceived greater challenges related to parental concerns and parent or child logistical barriers than study implementation and ethics or regulatory barriers as barriers to their practice serving as a trial site. Providers who had previously been an investigator for a pediatric trial were less likely to be concerned with potential barriers than non-investigators. Understanding the barriers that limit pediatric providers from collaboration or inhibit their participation is key to designing effective interventions to optimize pediatric trial participation.
DNA enzymes as potential therapeutics: towards clinical application of 10-23 DNAzymes.
Fokina, Alesya A; Stetsenko, Dmitry A; François, Jean-Christophe
2015-05-01
Ongoing studies on the inhibition of gene expression at the mRNA level have identified several types of specific inhibitors such as antisense oligonucleotides, small interfering RNA, ribozymes and DNAzymes (Dz). After its discovery in 1997, the 10-23 Dz (which can cleave RNA efficiently and site-specifically, has flexible design, is independent from cell mechanisms, does not require expensive chemical modifications for effective use in vivo) has been employed to downregulate a range of therapeutically important genes. Recently, 10-23 Dzs have taken their first steps into clinical trials. This review focuses predominantly on Dz applications as potential antiviral, antibacterial, anti-cancer and anti-inflammatory agents as well as for the treatment of cardiovascular disease and diseases of CNS, summarizing results of their clinical trials up to the present day. In comparison with antisense oligonucleotides and small interfering RNAs, Dzs do not usually show off-target effects due to their high specificity and lack of immunogenicity in vivo. As more results of clinical trials carried out so far are gradually becoming available, Dzs may turn out to be safe and well-tolerated therapeutics in humans. Therefore, there is a good chance that we may witness a deoxyribozyme drug reaching the clinic in the near future.
MacPherson, Hugh; Thomas, Kate
2008-04-01
In the literature on acupuncture research, the active (or specific) component of acupuncture is almost always presented as acupuncture needling alone. However, specific components, by definition, should include all interventions driven by acupuncture theory that are also believed to be causally associated with outcome. In this paper, we explore the delivery of self-help advice as a component of the process of acupuncture care, and discuss the implications for future trial designs. In a nested qualitative study, six acupuncturists were interviewed about the treatments they provided within a pragmatic clinical trial. The acupuncturists practised individualised acupuncture according to traditional principles. Audiotapes were transcribed and coded and the contents analysed by case and by theme. The analysis focuses on a priori and emergent themes associated with the process of delivering self-help advice as described by the practitioners. Individualised self-help advice is seen by practitioners as being an integral part of the acupuncture treatment that they provide for patients with low back pain. Several categories of generic advice were described; all were embedded in the acupuncture diagnosis. These included; movement, exercise and stretching to move 'qi stagnation'; rest in cases of 'qi deficiency'; diet when the digestive system was compromised; protection from the elements where indicated by the diagnosis, e.g. Bi Syndrome. According to the practitioners, longer-term benefits require the active participation of patients in their self-care. Simplified concepts derived from acupuncture theory, such as 'stagnation' and 'energy', are employed as an integral part of the process of care, in order to engage patients in lifestyle changes, help them to understand their condition, and to see ways in which they can help themselves. Within acupuncture care, self-help advice is not seen as an 'add-on' but rather as an integral and interactive component of a theory-based complex intervention. Studies designed to evaluate the overall effectiveness of traditional acupuncture should accommodate the full range of therapeutic components, strategies and related patient-centred treatment processes. In acupuncture trials, non-needling components, such as self-help advice, when drawn directly from the diagnosis and integral to the process of care, should not be misclassified as incidental, non-specific, or placebo if we are to accurately assess the value of treatment as delivered.
2010-01-01
Background The life-time incidence of low back pain is high and diagnoses of spinal stenosis and disc prolapse are increasing. Consequently, there is a steady rise in surgical interventions for these conditions. Current evidence suggests that while the success of surgery is incomplete, it is superior to conservative interventions. A recent survey indicates that there are large differences in the type and intensity of rehabilitation, if any, provided after spinal surgery as well as in the restrictions and advice given to patients in the post-operative period. This trial will test the hypothesis that functional outcome following two common spinal operations can be improved by a programme of post-operative rehabilitation that combines professional support and advice with graded active exercise and/or an educational booklet based on evidence-based messages and advice. Methods/Design The study design is a multi-centre, factorial, randomised controlled trial with patients stratified by surgeon and operative procedure. The trial will compare the effectiveness and cost-effectiveness of a rehabilitation programme and an education booklet for the postoperative management of patients undergoing discectomy or lateral nerve root decompression, each compared with "usual care"using a 2 × 2 factorial design. The trial will create 4 sub-groups; rehabilitation-only, booklet-only, rehabilitation-plus-booklet, and usual care only. The trial aims to recruit 344 patients, which equates to 86 patients in each of the four sub-groups. All patients will be assessed for functional ability (through the Oswestry Disability Index - a disease specific functional questionnaire), pain (using visual analogue scales), and satisfaction pre-operatively and then at 6 weeks, 3, 6 and 9 months and 1 year post-operatively. This will be complemented by a formal analysis of cost-effectiveness. Discussion This trial will determine whether the outcome of spinal surgery can be enhanced by either a post-operative rehabilitation programme or an evidence-based advice booklet or a combination of the two and as such will contribute to our knowledge on how to manage spinal surgery patients in the post-operative period. Trial Registration Current controlled trials ISRCTN46782945 UK CRN ID: 2670 PMID:20102625
Copeland, Robert J; Horspool, Kimberley; Humphreys, Liam; Scott, Emma
2016-02-24
Recruitment issues continue to impact a large number of trials. Sharing recruitment information is vital to supporting researchers to accurately predict recruitment and to manage the risk of poor recruitment during study design and implementation. The purpose of this article is to build on the knowledge available to researchers on recruiting to community-based trials. A critical commentary of the recruitment challenges encountered during the Booster Study, a randomised controlled trial in which researchers investigated the effectiveness of a motivational interviewing style intervention on the maintenance of physical activity. An overview of recruitment is provided, as well as strategies employed to recruit prospective participants and possible barriers to recruitment. Two hundred eighty-two people, 47 % of the original target, were recruited through mail-outs, with secondary recruitment pathways yielding no additional participants. The research team encountered problems with recontacting interested participants and providing study materials in non-English languages. A lower response rate to the mail-out and a greater number of non-contactable participants in the full study than in the pilot study resulted in a smaller pool of eligible participants from the brief intervention eligible for recruitment into the randomised controlled trial. Despite using widely accepted recruitment strategies and incorporating new recruitment tactics in response to challenges, the Booster Study investigators failed to randomise a sufficient number of participants. Recruitment in trials of community-based behavioural interventions may have different challenges than trials based on clinical or primary care pathways. Specific challenges posed by the complexity of the study design and problems with staffing and resources were exacerbated by the need to revise upwards the number of mailed invitations as a result of the pilot study. Researchers should ensure study design facilitates recruitment and consider the implications of changing recruitment on the operational aspects of the trial. Where possible, the impact of new strategies should be measured, and recruitment successes and challenges should be shared with those planning similar studies. ISRCTN56495859 (registered on 12 February 2009); NCT00836459 (registered on 3 February 2009).
2014-01-01
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. PMID:24628821
2009-01-01
Background A strong increase in smoking is noted especially among adolescents. In the Netherlands, about 5% of all 10-year olds, 25% of all 13-year olds and 62% of all 17-year olds report ever smoking. In the U.S., an intervention program called 'Smoke-free Kids' was developed to prevent children from smoking. The present study aims to assess the effects of this home-based smoking prevention program in the Netherlands. Methods/Design A randomized controlled trial is conducted among 9 to 11-year old children of primary schools. Participants are randomly assigned to the intervention and control conditions. The intervention program consists of five printed activity modules designed to improve parenting skills specific to smoking prevention and parent-child communication regarding smoking. These modules will include additional sheets with communication tips. The modules for the control condition will include solely information on smoking and tobacco use. Initiation of cigarette smoking (first instance of puffing on a lighted cigarette), susceptibility to cigarette smoking, smoking-related cognitions, and anti-smoking socialization will be the outcome measures. To collect the data, telephone interviews with mothers as well as with their child will be conducted at baseline. Only the children will be examined at post-intervention follow-ups (6, 12, 24, and 36 months after the baseline). Discussion This study protocol describes the design of a randomized controlled trial that will evaluate the effectiveness of a home-based smoking prevention program. We expect that a significantly lower number of children will start smoking in the intervention condition compared to control condition as a direct result of this intervention. If the program is effective, it is applicable in daily live, which will facilitate implementation of the prevention protocol. Trial registration Netherlands Trial Register NTR1465 PMID:20025727
Efficacy of web-based personalized normative feedback: a two-year randomized controlled trial.
Neighbors, Clayton; Lewis, Melissa A; Atkins, David C; Jensen, Megan M; Walter, Theresa; Fossos, Nicole; Lee, Christine M; Larimer, Mary E
2010-12-01
Web-based brief alcohol interventions have the potential to reach a large number of individuals at low cost; however, few controlled evaluations have been conducted to date. The present study was designed to evaluate the efficacy of gender-specific versus gender-nonspecific personalized normative feedback (PNF) with single versus biannual administration in a 2-year randomized controlled trial targeting a large sample of heavy-drinking college students. Participants included 818 freshmen (57.6% women; 42% non-Caucasian) who reported 1 or more heavy-drinking episodes in the previous month at baseline. Participants were randomly assigned in a 2 (gender-specific vs. gender-nonspecific PNF) × 2 (single vs. biannual administration of PNF) + 1 (attention control) design. Assessments occurred every 6 months for a 2-year period. Results from hierarchical generalized linear models provided modest effects on weekly drinking and alcohol-related problems but not on heavy episodic drinking. Relative to control, gender-specific biannual PNF was associated with reductions over time in weekly drinking (d = -0.16, 95% CI [-0.02, -0.31]), and this effect was partially mediated by changes in perceived norms. For women, but not men, gender-specific biannual PNF was associated with reductions over time in alcohol-related problems relative to control (d = -0.29, 95% CI [-0.15, -0.58]). Few other effects were evident. The present research provides modest support for the use of biannually administered web-based gender-specific PNF as an alternative to more costly indicated prevention strategies. (c) 2010 APA, all rights reserved.
2011-01-01
Background Suicide attempts (SA) constitute a serious clinical problem. People who attempt suicide are at high risk of further repetition. However, no interventions have been shown to be effective in reducing repetition in this group of patients. Methods/Design Multicentre randomized controlled trial. We examine the effectiveness of «ALGOS algorithm»: an intervention based in a decisional tree of contact type which aims at reducing the incidence of repeated suicide attempt during 6 months. This algorithm of case management comprises the two strategies of intervention that showed a significant reduction in the number of SA repeaters: systematic telephone contact (ineffective in first-attempters) and «Crisis card» (effective only in first-attempters). Participants who are lost from contact and those refusing healthcare, can then benefit from «short letters» or «postcards». Discussion ALGOS algorithm is easily reproducible and inexpensive intervention that will supply the guidelines for assessment and management of a population sometimes in difficulties with healthcare compliance. Furthermore, it will target some of these subgroups of patients by providing specific interventions for optimizing the benefits of case management strategy. Trial Registration The study was registered with the ClinicalTrials.gov Registry; number: NCT01123174. PMID:21194496
Group sequential designs for stepped-wedge cluster randomised trials.
Grayling, Michael J; Wason, James Ms; Mander, Adrian P
2017-10-01
The stepped-wedge cluster randomised trial design has received substantial attention in recent years. Although various extensions to the original design have been proposed, no guidance is available on the design of stepped-wedge cluster randomised trials with interim analyses. In an individually randomised trial setting, group sequential methods can provide notable efficiency gains and ethical benefits. We address this by discussing how established group sequential methodology can be adapted for stepped-wedge designs. Utilising the error spending approach to group sequential trial design, we detail the assumptions required for the determination of stepped-wedge cluster randomised trials with interim analyses. We consider early stopping for efficacy, futility, or efficacy and futility. We describe first how this can be done for any specified linear mixed model for data analysis. We then focus on one particular commonly utilised model and, using a recently completed stepped-wedge cluster randomised trial, compare the performance of several designs with interim analyses to the classical stepped-wedge design. Finally, the performance of a quantile substitution procedure for dealing with the case of unknown variance is explored. We demonstrate that the incorporation of early stopping in stepped-wedge cluster randomised trial designs could reduce the expected sample size under the null and alternative hypotheses by up to 31% and 22%, respectively, with no cost to the trial's type-I and type-II error rates. The use of restricted error maximum likelihood estimation was found to be more important than quantile substitution for controlling the type-I error rate. The addition of interim analyses into stepped-wedge cluster randomised trials could help guard against time-consuming trials conducted on poor performing treatments and also help expedite the implementation of efficacious treatments. In future, trialists should consider incorporating early stopping of some kind into stepped-wedge cluster randomised trials according to the needs of the particular trial.
Khan, Arif; Kolts, Russell L; Thase, Michael E; Krishnan, K Ranga Rama; Brown, Walter
2004-11-01
The authors examined which, if any, research design features and patient characteristics would significantly differ between successful and unsuccessful antidepressant trials. Clinical trial data were reviewed for nine antidepressants approved by the Food and Drug Administration between 1985 and 2000. From the antidepressant research programs on these medications, 52 clinical trials were included in the study. The authors evaluated trial design features, patient characteristics, and difference in response between placebo and antidepressant. Nine trial design features and patient characteristics were present in the research programs for all nine of the antidepressants. The severity of depressive symptoms before patient randomization, the dosing schedule (flexible versus fixed), the number of treatment arms, and the percentage of female patients were significantly associated with the difference in response to antidepressant and placebo. The duration of the antidepressant trial, number of patients per treatment arm, number of sites, and mean age of the patients were similar in successful trials (with a greater antidepressant-placebo difference) and less successful trials (with a smaller antidepressant-placebo difference). These findings may help in the design of future antidepressant trials.
Tvete, Ingunn F; Olsen, Inge C; Fagerland, Morten W; Meland, Nils; Aldrin, Magne; Smerud, Knut T; Holden, Lars
2012-04-01
In active run-in trials, where patients may be excluded after a run-in period based on their response to the treatment, it is implicitly assumed that patients have individual treatment effects. If individual patient data are available, active run-in trials can be modelled using patient-specific random effects. With more than one trial on the same medication available, one can obtain a more precise overall treatment effect estimate. We present a model for joint analysis of a two-sequence, four-period cross-over trial (AABB/BBAA) and a three-sequence, two-period active run-in trial (AB/AA/A), where the aim is to investigate the effect of a new treatment for patients with pain due to osteoarthritis. Our approach enables us to separately estimate the direct treatment effect for all patients, for the patients excluded after the active run-in trial prior to randomisation, and for the patients who completed the active run-in trial. A similar model approach can be used to analyse other types of run-in trials, but this depends on the data and type of other trials available. We assume equality of the various carry-over effects over time. The proposed approach is flexible and can be modified to handle other designs. Our results should be encouraging for those responsible for planning cost-efficient clinical development programmes.
Huang, Grant D; Bull, Jonca; Johnston McKee, Kelly; Mahon, Elizabeth; Harper, Beth; Roberts, Jamie N
2018-03-01
Patient recruitment is widely recognized as a key determinant of success for clinical trials. Yet a substantial number of trials fail to reach recruitment goals-a situation that has important scientific, financial, ethical, and policy implications. Further, there are important effects on stakeholders who directly contribute to the trial including investigators, sponsors, and study participants. Despite efforts over multiple decades to identify and address barriers, recruitment challenges persist. To advance a more comprehensive approach to trial recruitment, the Clinical Trials Transformation Initiative (CTTI) convened a project team to examine the challenges and to issue actionable, evidence-based recommendations for improving recruitment planning that extend beyond common study-specific strategies. We describe our multi-stakeholder effort to develop a framework that delineates three areas essential to strategic recruitment planning efforts: (1) trial design and protocol development, (2) trial feasibility and site selection, and (3) communication. Our recommendations propose an upstream approach to recruitment planning that has the potential to produce greater impact and reduce downstream barriers. Additionally, we offer tools to help facilitate adoption of the recommendations. We hope that our framework and recommendations will serve as a guide for initial efforts in clinical trial recruitment planning irrespective of disease or intervention focus, provide a common basis for discussions in this area and generate targets for further analysis and continual improvement. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.
Catenacci, Daniel V T
2015-05-01
The promise of 'personalized cancer care' with therapies toward specific molecular aberrations has potential to improve outcomes. However, there is recognized heterogeneity within any given tumor-type from patient to patient (inter-patient heterogeneity), and within an individual (intra-patient heterogeneity) as demonstrated by molecular evolution through space (primary tumor to metastasis) and time (after therapy). These issues have become hurdles to advancing cancer treatment outcomes with novel molecularly targeted agents. Classic trial design paradigms are challenged by heterogeneity, as they are unable to test targeted therapeutics against low frequency genomic 'oncogenic driver' aberrations with adequate power. Usual accrual difficulties to clinical trials are exacerbated by low frequencies of any given molecular driver. To address these challenges, there is need for innovative clinical trial designs and strategies implementing novel diagnostic biomarker technologies to account for inter-patient molecular diversity and scarce tissue for analysis. Importantly, there is also need for pre-defined treatment priority algorithms given numerous aberrations commonly observed within any one individual sample. Access to multiple available therapeutic agents simultaneously is crucial. Finally intra-patient heterogeneity through time may be addressed by serial biomarker assessment at the time of tumor progression. This report discusses various 'next-generation' biomarker-driven trial designs and their potentials and limitations to tackle these recognized molecular heterogeneity challenges. Regulatory hurdles, with respect to drug and companion diagnostic development and approval, are considered. Focus is on the 'Expansion Platform Design Types I and II', the latter demonstrated with a first example, 'PANGEA: Personalized Anti-Neoplastics for Gastro-Esophageal Adenocarcinoma'. Applying integral medium-throughput genomic and proteomic assays along with a practical biomarker assessment and treatment algorithm, 'PANGEA' attempts to address the problem of heterogeneity towards successful implementation of molecularly targeted therapies. Copyright © 2014 The Author. Published by Elsevier B.V. All rights reserved.
Paula Soares; Margarida Tome
2000-01-01
In Portugal, several eucalyptus spacing trials cover a relatively broad range of experimental designs: trials with a non-randomized block design with plots of different size and number of trees per plot; trials based on a non-systematic design in which spacings were randomized resulting in a factorial arrangement with plots of different size and shape and equal number...
How individual participant data meta-analyses have influenced trial design, conduct, and analysis
Tierney, Jayne F.; Pignon, Jean-Pierre; Gueffyier, Francois; Clarke, Mike; Askie, Lisa; Vale, Claire L.; Burdett, Sarah; Alderson, P.; Askie, L.; Bennett, D.; Burdett, S.; Clarke, M.; Dias, S.; Emberson, J.; Gueyffier, F.; Iorio, A.; Macleod, M.; Mol, B.W.; Moons, C.; Parmar, M.; Perera, R.; Phillips, R.; Pignon, J.P.; Rees, J.; Reitsma, H.; Riley, R.; Rovers, M.; Rydzewska, L.; Schmid, C.; Shepperd, S.; Stenning, S.; Stewart, L.; Tierney, J.; Tudur Smith, C.; Vale, C.; Welge, J.; White, I.; Whiteley, W.
2015-01-01
Objectives To demonstrate how individual participant data (IPD) meta-analyses have impacted directly on the design and conduct of trials and highlight other advantages IPD might offer. Study Design and Setting Potential examples of the impact of IPD meta-analyses on trials were identified at an international workshop, attended by individuals with experience in the conduct of IPD meta-analyses and knowledge of trials in their respective clinical areas. Experts in the field who did not attend were asked to provide any further examples. We then examined relevant trial protocols, publications, and Web sites to verify the impacts of the IPD meta-analyses. A subgroup of workshop attendees sought further examples and identified other aspects of trial design and conduct that may inform IPD meta-analyses. Results We identified 52 examples of IPD meta-analyses thought to have had a direct impact on the design or conduct of trials. After screening relevant trial protocols and publications, we identified 28 instances where IPD meta-analyses had clearly impacted on trials. They have influenced the selection of comparators and participants, sample size calculations, analysis and interpretation of subsequent trials, and the conduct and analysis of ongoing trials, sometimes in ways that would not possible with systematic reviews of aggregate data. We identified additional potential ways that IPD meta-analyses could be used to influence trials. Conclusions IPD meta-analysis could be better used to inform the design, conduct, analysis, and interpretation of trials. PMID:26186982
Cooper, Stephen A; Desjardins, Paul J; Turk, Dennis C; Dworkin, Robert H; Katz, Nathaniel P; Kehlet, Henrik; Ballantyne, Jane C; Burke, Laurie B; Carragee, Eugene; Cowan, Penney; Croll, Scott; Dionne, Raymond A; Farrar, John T; Gilron, Ian; Gordon, Debra B; Iyengar, Smriti; Jay, Gary W; Kalso, Eija A; Kerns, Robert D; McDermott, Michael P; Raja, Srinivasa N; Rappaport, Bob A; Rauschkolb, Christine; Royal, Mike A; Segerdahl, Märta; Stauffer, Joseph W; Todd, Knox H; Vanhove, Geertrui F; Wallace, Mark S; West, Christine; White, Richard E; Wu, Christopher
2016-02-01
This article summarizes the results of a meeting convened by the Initiative on Methods, Measurement, and Pain Assessment in Clinical Trials (IMMPACT) on key considerations and best practices governing the design of acute pain clinical trials. We discuss the role of early phase clinical trials, including pharmacokinetic-pharmacodynamic (PK-PD) trials, and the value of including both placebo and active standards of comparison in acute pain trials. This article focuses on single-dose and short-duration trials with emphasis on the perioperative and study design factors that influence assay sensitivity. Recommendations are presented on assessment measures, study designs, and operational factors. Although most of the methodological advances have come from studies of postoperative pain after dental impaction, bunionectomy, and other surgeries, the design considerations discussed are applicable to many other acute pain studies conducted in different settings.
Djulbegovic, Benjamin; Cantor, Alan; Clarke, Mike
2003-01-01
Previous research has identified methodological problems in the design and conduct of randomized trials that could, if left unaddressed, lead to biased results. In this report we discuss one such problem, inadequate control intervention, and argue that it can be by far the most important design characteristic of randomized trials in overestimating the effect of new treatments. Current guidelines for the design and reporting of randomized trials, such as the Consolidated Standards of Reporting Trials (CONSORT) statement, do not address the choice of the comparator intervention. We argue that an adequate control intervention can be selected if people designing a trial explicitly take into consideration the ethical principle of equipoise, also known as "the uncertainty principle."
Jackson, Jeanne; Mandel, Deborah; Blanchard, Jeanine; Carlson, Mike; Cherry, Barbara; Azen, Stanley; Chou, Chih-Ping; Jordan-Marsh, Maryalice; Forman, Todd; White, Brett; Granger, Douglas; Knight, Bob; Clark, Florence
2011-01-01
Background Community-dwelling older adults are at risk for declines in physical health, cognition, and psychosocial well-being. However, their enactment of active and health-promoting lifestyles can reduce such declines. Purpose The purpose of this article is to describe the USC Well Elderly II study, a randomized clinical trial designed to test the effectiveness of a healthy lifestyle program for elders, and document how various methodological challenges were addressed during the course of the trial. Methods In the study, 460 ethnically diverse elders recruited from a variety of sites in the urban Los Angeles area were enrolled in a randomized experiment involving a crossover design component. Within either the first or second six month phase of their study involvement, each elder received a lifestyle intervention designed to improve a variety of aging outcomes. At 4–5 time points over an 18–24 month interval, the research participants were assessed on measures of healthy activity, coping, social support, perceived control, stress-related biomarkers, perceived physical health, psychosocial well-being, and cognitive functioning to test the effectiveness of the intervention and document the process mechanisms responsible for its effects. Results The study protocol was successfully implemented, including the enrollment of study sites, the recruitment of 460 older adults, administration of the intervention, adherence to the plan for assessment, and establishment of a large computerized data base. Limitations Methodological challenges were encountered in the areas of site recruitment, participant recruitment, testing, and intervention delivery. Conclusions The completion of clinical trials involving elders from numerous local sites requires careful oversight and anticipation of threats to the study design that stem from: (a) social situations that are particular to specific study sites; and (b) physical, functional, and social challenges pertaining to the elder population. PMID:19254939
Jackson, Jeanne; Mandel, Deborah; Blanchard, Jeanine; Carlson, Mike; Cherry, Barbara; Azen, Stanley; Chou, Chih-Ping; Jordan-Marsh, Maryalice; Forman, Todd; White, Brett; Granger, Douglas; Knight, Bob; Clark, Florence
2009-02-01
Community-dwelling older adults are at risk for declines in physical health, cognition, and psychosocial well-being. However, their enactment of active and health-promoting lifestyles can reduce such declines. The purpose of this article is to describe the USC Well Elderly II study, a randomized clinical trial designed to test the effectiveness of a healthy lifestyle program for elders, and document how various methodological challenges were addressed during the course of the trial. In the study, 460 ethnically diverse elders recruited from a variety of sites in the urban Los Angeles area were enrolled in a randomized experiment involving a crossover design component. Within either the first or second 6-month phase of their study involvement, each elder received a lifestyle intervention designed to improve a variety of aging outcomes. At 4-5 time points over an 18-24 month interval, the research participants were assessed on measures of healthy activity, coping, social support, perceived control, stress-related biomarkers, perceived physical health, psychosocial well-being, and cognitive functioning to test the effectiveness of the intervention and document the process mechanisms responsible for its effects. The study protocol was successfully implemented, including the enrollment of study sites, the recruitment of 460 older adults, administration of the intervention, adherence to the plan for assessment, and establishment of a large computerized data base. Methodological challenges were encountered in the areas of site recruitment, participant recruitment, testing, and intervention delivery. The completion of clinical trials involving elders from numerous local sites requires careful oversight and anticipation of threats to the study design that stem from: (a) social situations that are particular to specific study sites; and (b) physical, functional, and social challenges pertaining to the elder population.
Yang, Mingxiao; Feng, Yue; Pei, Hong; Deng, Shufang; Wang, Minyu; Xiao, Xianjun; Zheng, Hui; Lai, Zhenhong; Chen, Jiao; Li, Xiang; He, Xiaoguo; Liang, Fanrong
2014-10-29
Low back pain is a common, disabling musculoskeletal disorder in both developing and developed countries. Although often recommended, the potential efficacy of massage therapy in general, and Chinese massage (tuina) in particular, for relief of chronic low back pain (CLBP) has not been fully established due to inadequate sample sizes, low methodological quality, and subclinical dosing regimens of trials to date. Thus, the purpose of this randomized controlled trial (RCT) is to evaluate the comparative effectiveness of tuina massage therapy versus conventional analgesics for CLBP. The present study is a single center, two-arm, open-label RCT. A total of 150 eligible CLBP patients will be randomly assigned to either a tuina treatment group or a conventional drug control group in a 1:1 ratio. Patients in the tuina group receive a 20 minutes, 4-step treatment protocol which includes both structural and relaxation massage, administered in 20 sessions over a period of 4 weeks. Patients in the conventional drug control group are instructed to take a specific daily dose of ibuprofen. The primary outcome measure is the change from baseline back pain and function, measured by Roland-Morris Disability Questionnaire, at two months. Secondary outcome measures include the visual analogue scale, Japanese orthopedic association score (JOAS), and McGill pain questionnaire. The design and methodological rigor of this trial will allow for collection of valuable data to evaluate the efficacy of a specific tuina protocol for treating CLBP. This trial will therefore contribute to providing a solid foundation for clinical treatment of CLBP, as well as future research in massage therapy. This trial was registered with ClinicalTrials.gov of the National Institute of Health on 22 October 2013 (http://NCT01973010).
Effectiveness of befriending interventions: a systematic review and meta-analysis
Siette, Joyce; Cassidy, Megan; Priebe, Stefan
2017-01-01
Objective Befriending is an emotional supportive relationship in which one-to-one companionship is provided on a regular basis by a volunteer. It is commonly and increasingly offered by the voluntary sector for individuals with distressing physical and mental conditions. However, the effectiveness of this intervention on health outcomes is largely unknown. We aim to conduct a systematic review of the benefits of befriending. Design Systematic review. Methods A systematic search of electronic databases was conducted to identify randomised controlled trials and quasi-experimental trials of befriending for a range of physical and mental health indications including depression, anxiety, mental illness, cancer, physical illness and dementia. Main outcomes included patient-relevant and disease-specific outcomes, such as depression, loneliness, quality of life, self-esteem, social support and well-being. Results A total of 14 trials (2411 participants) were included; 7 were judged at low risk of bias. Most trials showed improvement in symptoms associated with befriending but these associations did not reach statistical significance in all trials. Befriending was significantly associated with better patient-reported outcomes across primary measures (standardised mean difference 0.18 (95% CI, −0.002 to 0.36, I2=26%, seven trials)). However, there was no significant benefit on single outcomes, including depression, quality of life, loneliness ratings, self-esteem measures, social support structures and well-being. Conclusions There was moderate quality evidence to support the use of befriending for the treatment of individuals with different physical and mental health conditions. This evidence refers to an overall improvement benefit in patient-reported primary outcomes, although with a rather small effect size. The current evidence base does not allow for firm conclusions on more specific outcomes. Future trials should hypothesise a model for the precise effects of befriending and use specified inclusion and outcome criteria. PMID:28446525
2012-01-01
Background Women with cancer are significantly more likely to fall than women without cancer placing them at higher risk of fall-related fractures, other injuries and disability. Currently, no evidence-based fall prevention strategies exist that specifically target female cancer survivors. The purpose of the GET FIT (Group Exercise Training for Functional Improvement after Treatment) trial is to compare the efficacy of two distinct types of exercise, tai chi versus strength training, to prevent falls in women who have completed treatment for cancer. The specific aims of this study are to: 1) Determine and compare the efficacy of both tai chi training and strength training to reduce falls in older female cancer survivors, 2) Determine the mechanism(s) by which tai chi and strength training each reduces falls and, 3) Determine whether or not the benefits of each intervention last after structured training stops. Methods/Design We will conduct a three-group, single-blind, parallel design, randomized controlled trial in women, aged 50–75 years old, who have completed chemotherapy for cancer comparing 1) tai chi 2) strength training and 3) a placebo control group of seated stretching exercise. Women will participate in supervised study programs twice per week for six months and will be followed for an additional six months after formal training stops. The primary outcome in this study is falls, which will be prospectively tracked by monthly self-report. Secondary outcomes are maximal leg strength measured by isokinetic dynamometry, postural stability measured by computerized dynamic posturography and physical function measured by the Physical Performance Battery, all measured at baseline, 3, 6 and 12 months. The sample for this trial (N=429, assuming 25% attrition) will provide adequate statistical power to detect at least a 47% reduction in the fall rate over 1 year by being in either of the 2 exercise groups versus the control group. Discussion The GET FIT trial will provide important new knowledge about preventing falls using accessible and implementable exercise interventions for women following chemotherapy for cancer. ClinicalTrials.gov NCT01635413 PMID:23217054
A perspective on B-cell-targeting therapy for SLE.
Looney, R John; Anolik, Jennifer; Sanz, Inaki
2010-02-01
In recent years, large controlled trials have tested several new agents for systemic lupus erythematosus (SLE). Unfortunately, none of these trials has met its primary outcome. This does not mean progress has not been made. In fact, a great deal has been learned about doing clinical trials in lupus and about the biological and clinical effects of the drugs being tested. Many of these drugs were designed to target B cells directly, e.g., rituximab, belimumab, epratuzumab, and transmembrane activator and calcium modulator and cyclophilin ligand interactor-immunoglobulin (TACI-Ig). The enthusiasm for targeting B cells derives from substantial evidence showing the critical role of B cells in murine models of SLE, as well promising results from multiple open trials with rituximab, a chimeric anti-CD20 monoclonal antibody that specifically depletes B cells (Martin and Chan in Immunity 20(5):517-527, 2004; Sobel et al. in J Exp Med 173:1441-1449, 1991; Silverman and Weisman in Arthritis Rheum 48:1484-1492, 2003; Silverman in Arthritis Rheum 52(4):1342, 2005; Shlomchik et al. in Nat Rev Immunol 1:147-153, 2001; Looney et al. in Arthritis Rheum 50:2580-2589, 2004; Lu et al. in Arthritis Rheum 61(4):482-487, 2009; Saito et al. in Lupus 12(10):798-800, 2003; van Vollenhoven et al. in Scand J Rheumatol 33(6):423-427, 2004; Sfikakis et al. Arthritis Rheum 52(2):501-513, 2005). Why have the controlled trials of B-cell-targeting therapies failed to demonstrate efficacy? Were there flaws in design or execution of these trials? Or, were promising animal studies and open trials misleading, as so often happens? This perspective discusses the current state of B-cell-targeting therapies for human lupus and the future development of these therapies.
Carney, Patricia A.; Tucker, Erin K.; Newby, Timothy A.; Beer, Tomasz M.
2014-01-01
Objective To assess the feasibility, acceptability and changes in knowledge among cancer patients assigned to receive a 160 page book on experimental cancer therapies and clinical trials. Methods We enrolled 20 patients with cancer who had never participated in a clinical trial, and randomly assigned them to receive the book either during Week 1or Week 4 of the study. We collected baseline patient demographic and cancer related information as well as knowledge about cancer clinical trials at Week 0. Follow-up surveys were administered at Weeks 3 and 6 for both study groups. Comparisons were made within and between groups randomized to receive the book Early (at Week 1) to those who received it Later (at Week 4). Results One hundred percent of data were captured in both groups at baseline, which decreased to 77.8% by Week 6. The vast majority of participants found the book moderately or very useful (89% in the Early Group at Week 3 and 95.5% in the Late Group at Week 6). Within group pair-wise comparisons found significant difference between baseline and Week 6 in content-specific knowledge scores among participants in the Late Group (79% vs. 92.1%, p=0.01). Global knowledge scores increased significantly for variables reflecting knowledge that promotes decisions to participate in clinical trials. Conclusions Providing published reading material to patients with cancer is both feasible and acceptable. Offering information to patients about cancer clinical trials, using a book designed for patients with cancer may influence knowledge related to decision to participate in clinical trials. PMID:24127249
Carney, Patricia A; Tucker, Erin K; Newby, Timothy A; Beer, Tomasz M
2014-03-01
This study was conducted to assess the feasibility, acceptability, and changes in knowledge among cancer patients assigned to receive a 160-page book on experimental cancer therapies and clinical trials. We enrolled 20 patients with cancer who had never participated in a clinical trial and randomly assigned them to receive the book either during week 1 or week 4 of the study. We collected baseline patient demographic and cancer-related information as well as knowledge about cancer clinical trials at week 0. Follow-up surveys were administered at weeks 3 and 6 for both study groups. Comparisons were made within and between groups randomized to receive the book early (at week 1) to those who received it later (at week 4). One hundred percent of data were captured in both groups at baseline, which decreased to 77.8% by week 6. The vast majority of participants found the book moderately or very useful (89% in the Early Group at week 3 and 95.5% in the Late Group at week 6). Within group pairwise comparisons found significant difference between baseline and week 6 in content-specific knowledge scores among participants in the Late Group [79% versus 92.1%, p = 0.01). Global knowledge scores increased significantly for variables reflecting knowledge that promotes decisions to participate in clinical trials. Providing published reading material to patients with cancer is both feasible and acceptable. Offering information to patients about cancer clinical trials, using a book designed for patients with cancer may influence knowledge related to decision to participate in clinical trials.
Gerardo, Charles J; Lavonas, Eric J; McKinney, Ross E
2014-10-01
In 2000, the US Food and Drug Administration approved CroFab(®) Crotalidae Polyvalent Immune Fab, ovine (FabAV), which had received orphan drug designation, for use in patients with minimal to moderate North American crotaline envenomations including copperhead snakes. As existing evidence on the effectiveness of FabAV for this indication is limited, wide practice variation in its use exists. In order to provide more definitive clinical evidence as to the role of this treatment, a new randomized, placebo-controlled trial of FabAV specifically for copperhead bites was initiated. In light of the existing US Food and Drug Administration approval, ethical considerations of participation in this trial have been raised. We discuss the ethical principles pertinent to this randomized, placebo-controlled trial with placebo arm. We apply an accepted framework for ethical research to this trial. Due to the evidence gap in the literature, wide-ranging treatment recommendations by medical experts, and broad practice variation, clinical equipoise exists in the treatment of copperhead envenomation with FabAV. The impact of this clinical equipoise on the value and scientific validity of the trial is discussed. The trial's risk-benefit ratio is also considered. Potential risks to the patients are minimized as the protocol includes a plan for rescue therapy in the event that patients progress to severe envenomation symptoms. Overall, risks are further minimized by the inclusion of an interim analysis with stopping rules based on demonstrated efficacy should the therapy clearly prove to be beneficial. Although a post-marketing clinical study of this nature is unusual for an approved indication, this trial adheres to all ethical preconditions found in existing guidelines for clinical research involving human subjects. © The Author(s) 2014.
Taylor, J; Scott, L J; Rogers, C A; Muldrew, A; O'Reilly, D; Wordsworth, S; Mills, N; Hogg, R; Violato, M; Harding, S P; Peto, T; Townsend, D; Chakravarthy, U; Reeves, B C
2016-01-01
Introduction Standard treatment for neovascular age-related macular degeneration (nAMD) is intravitreal injections of anti-VEGF drugs. Following multiple injections, nAMD lesions often become quiescent but there is a high risk of reactivation, and regular review by hospital ophthalmologists is the norm. The present trial examines the feasibility of community optometrists making lesion reactivation decisions. Methods The Effectiveness of Community vs Hospital Eye Service (ECHoES) trial is a virtual trial; lesion reactivation decisions were made about vignettes that comprised clinical data, colour fundus photographs, and optical coherence tomograms displayed on a web-based platform. Participants were either hospital ophthalmologists or community optometrists. All participants were provided with webinar training on the disease, its management, and assessment of the retinal imaging outputs. In a balanced design, 96 participants each assessed 42 vignettes; a total of 288 vignettes were assessed seven times by each professional group. The primary outcome is a participant's judgement of lesion reactivation compared with a reference standard. Secondary outcomes are the frequency of sight threatening errors; judgements about specific lesion components; participant-rated confidence in their decisions about the primary outcome; cost effectiveness of follow-up by optometrists rather than ophthalmologists. Discussion This trial addresses an important question for the NHS, namely whether, with appropriate training, community optometrists can make retreatment decisions for patients with nAMD to the same standard as hospital ophthalmologists. The trial employed a novel approach as participation was entirely through a web-based application; the trial required very few resources compared with those that would have been needed for a conventional randomised controlled clinical trial. PMID:26449197
Gaus, Wilhelm; Muche, Rainer
2013-05-01
Clinical studies provide formalised experience for evidence-based medicine (EBM). Many people consider a controlled randomised trial (CRT, identical to a randomised controlled trial RCT) to be the non-plus-ultra design. However, CRTs also have limitations. The problem is not randomisation itself but informed consent for randomisation and masking of therapies according to today's legal and ethical standards. We do not want to de-rate CRTs, but we would like to contribute to the discussion on clinical research methodology. Informed consent to a CRT and masking of therapies plainly select patients. The excellent internal validity of CRTs can be counterbalanced by poor external validity, because internal and external validity act as antagonists. In a CRT, patients may feel like guinea pigs, this can decrease compliance, cause protocol violations, reduce self-healing properties, suppress unspecific therapeutic effects and possibly even modify specific efficacy. A control group (comparative study) is most important for the degree of evidence achieved by a trial. Study control by detailed protocol and good clinical practice (controlled study) is second in importance and randomisation and masking is third (thus the sequence CRT instead of RCT). Controlled non-randomised trials are just as ambitious and detailed as CRTs. We recommend clinicians and biometricians to take high quality controlled non-randomised trials into consideration more often. They combine good internal and external validity, better suit daily medical practice, show better patient compliance and fewer protocol violations, deliver estimators unbiased by alienated patients, and perhaps provide a clearer explanation of the achieved success. Copyright © 2013 Elsevier Inc. All rights reserved.
Taylor, J; Scott, L J; Rogers, C A; Muldrew, A; O'Reilly, D; Wordsworth, S; Mills, N; Hogg, R; Violato, M; Harding, S P; Peto, T; Townsend, D; Chakravarthy, U; Reeves, B C
2016-01-01
IntroductionStandard treatment for neovascular age-related macular degeneration (nAMD) is intravitreal injections of anti-VEGF drugs. Following multiple injections, nAMD lesions often become quiescent but there is a high risk of reactivation, and regular review by hospital ophthalmologists is the norm. The present trial examines the feasibility of community optometrists making lesion reactivation decisions.MethodsThe Effectiveness of Community vs Hospital Eye Service (ECHoES) trial is a virtual trial; lesion reactivation decisions were made about vignettes that comprised clinical data, colour fundus photographs, and optical coherence tomograms displayed on a web-based platform. Participants were either hospital ophthalmologists or community optometrists. All participants were provided with webinar training on the disease, its management, and assessment of the retinal imaging outputs. In a balanced design, 96 participants each assessed 42 vignettes; a total of 288 vignettes were assessed seven times by each professional group.The primary outcome is a participant's judgement of lesion reactivation compared with a reference standard. Secondary outcomes are the frequency of sight threatening errors; judgements about specific lesion components; participant-rated confidence in their decisions about the primary outcome; cost effectiveness of follow-up by optometrists rather than ophthalmologists.DiscussionThis trial addresses an important question for the NHS, namely whether, with appropriate training, community optometrists can make retreatment decisions for patients with nAMD to the same standard as hospital ophthalmologists. The trial employed a novel approach as participation was entirely through a web-based application; the trial required very few resources compared with those that would have been needed for a conventional randomised controlled clinical trial.
Meinzer, Caitlyn; Martin, Renee; Suarez, Jose I
2017-09-08
In phase II trials, the most efficacious dose is usually not known. Moreover, given limited resources, it is difficult to robustly identify a dose while also testing for a signal of efficacy that would support a phase III trial. Recent designs have sought to be more efficient by exploring multiple doses through the use of adaptive strategies. However, the added flexibility may potentially increase the risk of making incorrect assumptions and reduce the total amount of information available across the dose range as a function of imbalanced sample size. To balance these challenges, a novel placebo-controlled design is presented in which a restricted Bayesian response adaptive randomization (RAR) is used to allocate a majority of subjects to the optimal dose of active drug, defined as the dose with the lowest probability of poor outcome. However, the allocation between subjects who receive active drug or placebo is held constant to retain the maximum possible power for a hypothesis test of overall efficacy comparing the optimal dose to placebo. The design properties and optimization of the design are presented in the context of a phase II trial for subarachnoid hemorrhage. For a fixed total sample size, a trade-off exists between the ability to select the optimal dose and the probability of rejecting the null hypothesis. This relationship is modified by the allocation ratio between active and control subjects, the choice of RAR algorithm, and the number of subjects allocated to an initial fixed allocation period. While a responsive RAR algorithm improves the ability to select the correct dose, there is an increased risk of assigning more subjects to a worse arm as a function of ephemeral trends in the data. A subarachnoid treatment trial is used to illustrate how this design can be customized for specific objectives and available data. Bayesian adaptive designs are a flexible approach to addressing multiple questions surrounding the optimal dose for treatment efficacy within the context of limited resources. While the design is general enough to apply to many situations, future work is needed to address interim analyses and the incorporation of models for dose response.
Dunn, Graham; Emsley, Richard; Liu, Hanhua; Landau, Sabine; Green, Jonathan; White, Ian; Pickles, Andrew
2015-11-01
The development of the capability and capacity to evaluate the outcomes of trials of complex interventions is a key priority of the National Institute for Health Research (NIHR) and the Medical Research Council (MRC). The evaluation of complex treatment programmes for mental illness (e.g. cognitive-behavioural therapy for depression or psychosis) not only is a vital component of this research in its own right but also provides a well-established model for the evaluation of complex interventions in other clinical areas. In the context of efficacy and mechanism evaluation (EME) there is a particular need for robust methods for making valid causal inference in explanatory analyses of the mechanisms of treatment-induced change in clinical outcomes in randomised clinical trials. The key objective was to produce statistical methods to enable trial investigators to make valid causal inferences about the mechanisms of treatment-induced change in these clinical outcomes. The primary objective of this report is to disseminate this methodology, aiming specifically at trial practitioners. The three components of the research were (1) the extension of instrumental variable (IV) methods to latent growth curve models and growth mixture models for repeated-measures data; (2) the development of designs and regression methods for parallel trials; and (3) the evaluation of the sensitivity/robustness of findings to the assumptions necessary for model identifiability. We illustrate our methods with applications from psychological and psychosocial intervention trials, keeping the technical details to a minimum, leaving the reporting of the more theoretical and mathematically demanding results for publication in appropriate specialist journals. We show how to estimate treatment effects and introduce methods for EME. We explain the use of IV methods and principal stratification to evaluate the role of putative treatment effect mediators and therapeutic process measures. These results are extended to the analysis of longitudinal data structures. We consider the design of EME trials. We focus on designs to create convincing IVs, bearing in mind assumptions needed to attain model identifiability. A key area of application that has become apparent during this work is the potential role of treatment moderators (predictive markers) in the evaluation of treatment effect mechanisms for personalised therapies (stratified medicine). We consider the role of targeted therapies and multiarm trials and the use of parallel trials to help elucidate the evaluation of mediators working in parallel. In order to demonstrate both efficacy and mechanism, it is necessary to (1) demonstrate a treatment effect on the primary (clinical) outcome, (2) demonstrate a treatment effect on the putative mediator (mechanism) and (3) demonstrate a causal effect from the mediator to the outcome. Appropriate regression models should be applied for (3) or alternative IV procedures, which account for unmeasured confounding, provided that a valid instrument can be identified. Stratified medicine may provide a setting where such instruments can be designed into the trial. This work could be extended by considering improved trial designs, sample size considerations and measurement properties. The project presents independent research funded under the MRC-NIHR Methodology Research Programme (grant reference G0900678).
Hein, Alexander; Gass, Paul; Walter, Christina Barbara; Taran, Florin-Andrei; Hartkopf, Andreas; Overkamp, Friedrich; Kolberg, Hans-Christian; Hadji, Peyman; Tesch, Hans; Ettl, Johannes; Wuerstlein, Rachel; Lounsbury, Debra; Lux, Michael P; Lüftner, Diana; Wallwiener, Markus; Müller, Volkmar; Belleville, Erik; Janni, Wolfgang; Fehm, Tanja N; Wallwiener, Diethelm; Ganslandt, Thomas; Ruebner, Matthias; Beckmann, Matthias W; Schneeweiss, Andreas; Fasching, Peter A; Brucker, Sara Y
2016-07-01
As breast cancer is a diverse disease, clinical trials are becoming increasingly diversified and are consequently being conducted in very small subgroups of patients, making study recruitment increasingly difficult. The aim of this study was to assess the use of data from a remote data entry system that serves a large national registry for metastatic breast cancer. The PRAEGNANT network is a real-time registry with an integrated biomaterials bank that was designed as a scientific study and as a means of identifying patients who are eligible for clinical trials, based on clinical and molecular information. Here, we report on the automated use of the clinical data documented to identify patients for a clinical trial (EMBRACA) for patients with metastatic breast cancer. The patients' charts were assessed by two independent physicians involved in the clinical trial and also by a computer program that tested patients for eligibility using a structured query language script. In all, 326 patients from two study sites in the PRAEGNANT network were included in the analysis. Using expert assessment, 120 of the 326 patients (37 %) appeared to be eligible for inclusion in the EMBRACA study; with the computer algorithm assessment, a total of 129 appeared to be eligible. The sensitivity of the computer algorithm was 0.87 and its specificity was 0.88. Using computer-based identification of patients for clinical trials appears feasible. With the instrument's high specificity, its application in a large cohort of patients appears to be feasible, and the workload for reassessing the patients is limited.
Sales, Myrla Patricia Reis; Polman, Remco; Hill, Keith D; Karaharju-Huisman, Tuire; Levinger, Pazit
2015-06-24
Exercise is an important and effective approach to preventing falls in older people, but adherence to exercise participation remains a persistent problem. A unique purpose-built exercise park was designed to provide a fun but physically challenging environment to support exercise in a community setting. This project is a randomised controlled trial designed to evaluate the effectiveness of an exercise intervention using an exercise park specifically designed for older people in reducing the risk of falls. This study will be a parallel randomised control trial with pre and post intervention design. One hundred and twenty people aged between 60 and 90 years old will be recruited from Melbourne suburbs and will be randomly allocated to either an exercise park intervention group (EPIG) or a control group (CG). The CG will receive social activities and an educational booklet on falls prevention. The BOOMER balance test will be used as the primary outcome measure. Secondary outcome measures will include hand grip strength, two minute walk test, lower limb strength test, spatio-temporal walking parameters, health related quality of life, feasibility, adherence, safety, and a number of other psychosocial measures. Outcome assessment will be conducted at baseline and at 18 and 26 weeks after intervention commencement. Participants will inform their falls and physical activity history for a 12-month period via monthly calendars. Mixed linear modelling incorporating intervention and control groups at the baseline and two follow up time points (18 weeks and 26 weeks after intervention commencement) will be used to assess outcomes. This planned trial will be the first to provide evidence if the exercise park can improve functional and physiological health, psychological and well-being. In addition, this study will provide empirical evidence for effectiveness and explore the barriers to participation and the acceptability of the senior exercise park in the Australian older community. This trial is registered with the Australian New Zealand Clinical Trials Registry-Registry No. ACTRN12614000700639 registered on Jul 3rd 2014.
2014-01-01
Background Osteoporosis and vertebral fracture can have a considerable impact on an individual’s quality of life. There is increasing evidence that physiotherapy including manual techniques and exercise interventions may have an important treatment role. This pragmatic randomised controlled trial will investigate the clinical and cost-effectiveness of two different physiotherapy approaches for people with osteoporosis and vertebral fracture, in comparison to usual care. Methods/Design Six hundred people with osteoporosis and a clinically diagnosed vertebral fracture will be recruited and randomly allocated to one of three management strategies, usual care (control - A), an exercise-based physiotherapy intervention (B) or a manual therapy-based physiotherapy intervention (C). Those in the usual care arm will receive a single session of education and advice, those in the active treatment arms (B + C) will be offered seven individual physiotherapy sessions over 12 weeks. The trial is designed as a prospective, adaptive single-blinded randomised controlled trial. An interim analysis will be completed and if one intervention is clearly superior the trial will be adapted at this point to continue with just one intervention and the control. The primary outcomes are quality of life measured by the disease specific QUALLEFO 41 and the Timed Loaded Standing test measured at 1 year. Discussion There are a variety of different physiotherapy packages used to treat patients with osteoporotic vertebral fracture. At present, the indication for each different therapy is not well defined, and the effectiveness of different modalities is unknown. Trial registration Reference number ISRCTN49117867. PMID:24422876
Smith, Shannon M; Jones, Judith K; Katz, Nathaniel P; Roland, Carl L; Setnik, Beatrice; Trudeau, Jeremiah J; Wright, Stephen; Burke, Laurie B; Comer, Sandra D; Dart, Richard C; Dionne, Raymond; Haddox, J David; Jaffe, Jerome H; Kopecky, Ernest A; Martell, Bridget A; Montoya, Ivan D; Stanton, Marsha; Wasan, Ajay D; Turk, Dennis C; Dworkin, Robert H
2017-11-01
Accurate assessment of inappropriate medication use events (ie, misuse, abuse, and related events) occurring in clinical trials is an important component in evaluating a medication's abuse potential. A meeting was convened to review all instruments measuring such events in clinical trials according to previously published standardized terminology and definitions. Only 2 approaches have been reported that are specifically designed to identify and classify misuse, abuse, and related events occurring in clinical trials, rather than to measure an individual's risk of using a medication inappropriately: the Self-Reported Misuse, Abuse, and Diversion (SR-MAD) instrument and the Misuse, Abuse, and Diversion Drug Event Reporting System (MADDERS). The conceptual basis, strengths, and limitations of these methods are discussed. To our knowledge, MADDERS is the only system available to comprehensively evaluate inappropriate medication use events prospectively to determine the underlying intent. MADDERS can also be applied retrospectively to completed trial data. SR-MAD can be used prospectively; additional development may be required to standardize its implementation and fully appraise the intent of inappropriate use events. Additional research is needed to further demonstrate the validity and utility of MADDERS as well as SR-MAD. Identifying a medication's abuse potential requires assessing inappropriate medication use events in clinical trials on the basis of a standardized event classification system. The strengths and limitations of the 2 published methods designed to evaluate inappropriate medication use events are reviewed, with recommended considerations for further development and current implementation. Copyright © 2017 American Pain Society. Published by Elsevier Inc. All rights reserved.
Current challenges for clinical trials of cardiovascular medical devices.
Zannad, Faiez; Stough, Wendy Gattis; Piña, Ileana L; Mehran, Roxana; Abraham, William T; Anker, Stefan D; De Ferrari, Gaetano M; Farb, Andrew; Geller, Nancy L; Kieval, Robert S; Linde, Cecilia; Redberg, Rita F; Stein, Kenneth; Vincent, Alphons; Woehrle, Holger; Pocock, Stuart J
2014-07-15
Several features of cardiovascular devices raise considerations for clinical trial conduct. Prospective, randomized, controlled trials remain the highest quality evidence for safety and effectiveness assessments, but, for instance, blinding may be challenging. In order to avoid bias and not confound data interpretation, the use of objective endpoints and blinding patients, study staff, core labs, and clinical endpoint committees to treatment assignment are helpful approaches. Anticipation of potential bias should be considered and planned for prospectively in a cardiovascular device trial. Prospective, single-arm studies (often referred to as registry studies) can provide additional data in some cases. They are subject to selection bias even when carefully designed; thus, they are generally not acceptable as the sole basis for pre-market approval of high risk cardiovascular devices. However, they complement the evidence base and fill the gaps unanswered by randomized trials. Registry studies present device safety and effectiveness in day-to-day clinical practice settings and detect rare adverse events in the post-market period. No single research design will be appropriate for every cardiovascular device or target patient population. The type of trial, appropriate control group, and optimal length of follow-up will depend on the specific device, its potential clinical benefits, the target patient population and the existence (or lack) of effective therapies, and its anticipated risks. Continued efforts on the part of investigators, the device industry, and government regulators are needed to reach the optimal approach for evaluating the safety and performance of innovative devices for the treatment of cardiovascular disease. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.
Biomarker-Guided Adaptive Trial Designs in Phase II and Phase III: A Methodological Review
Antoniou, Miranta; Jorgensen, Andrea L; Kolamunnage-Dona, Ruwanthi
2016-01-01
Background Personalized medicine is a growing area of research which aims to tailor the treatment given to a patient according to one or more personal characteristics. These characteristics can be demographic such as age or gender, or biological such as a genetic or other biomarker. Prior to utilizing a patient’s biomarker information in clinical practice, robust testing in terms of analytical validity, clinical validity and clinical utility is necessary. A number of clinical trial designs have been proposed for testing a biomarker’s clinical utility, including Phase II and Phase III clinical trials which aim to test the effectiveness of a biomarker-guided approach to treatment; these designs can be broadly classified into adaptive and non-adaptive. While adaptive designs allow planned modifications based on accumulating information during a trial, non-adaptive designs are typically simpler but less flexible. Methods and Findings We have undertaken a comprehensive review of biomarker-guided adaptive trial designs proposed in the past decade. We have identified eight distinct biomarker-guided adaptive designs and nine variations from 107 studies. Substantial variability has been observed in terms of how trial designs are described and particularly in the terminology used by different authors. We have graphically displayed the current biomarker-guided adaptive trial designs and summarised the characteristics of each design. Conclusions Our in-depth overview provides future researchers with clarity in definition, methodology and terminology for biomarker-guided adaptive trial designs. PMID:26910238
Wingo, Jonathan E.; Berger, Erik M.; Dellis, William O.; Knight, J. Chad; McClung, Joseph M.
2004-01-01
Objective: To determine if pre-exercise hydration with and without glycerol differentially affects physiologic and performance responses during mountain-bike races in the heat. Design and Setting: Testing (random, crossover, double-blind design) included the following 3 treatments administered in conjunction with a 30-mile mountain-bike race consisting of three 10-mile (16-km) loops: (1) no water during exercise (NE): water consumed before the race and no water consumed during the race, (2) glycerol (G): mixture of water and glycerol consumed before the race and water via 2 water bottles consumed during the race, and (3) water (W): water consumed before the race and water via 2 water bottles consumed during the race. Subjects stopped for 8 minutes after each 10-mile loop for collection of data. Subjects: Twelve heat-acclimated male mountain bikers with age = 24.5 ± 1.1 years, percentage of body fat = 14.3 ± 1.0%, mass = 76.9 ± 1.9 kg, height = 179 ± 2 cm. Measurements: We measured body weight, percentage of body fat, rectal temperature, blood lactate, blood glucose, urine volume, urine color, urine specific gravity, thirst sensation, thermal sensation, rating of perceived exertion, fluid consumption, heart rate, and sweat rate. Each subject completed the Environmental Symptoms Questionnaire. Results: The G trial was less dehydrated than the NE and W trials postexercise. Pre-exercise urine volume was less in the G trial than in the NE and W trials, and postexercise thirst was less in the G trial than the NE and W trials. Postexercise Environmental Symptoms Questionnaire scores were lower in the G trial than the NE or W trials. It is noteworthy that, although not significant, the G trial performed 5 minutes faster on loop 3 than the NE and W trials. Conclusions: Lower Environmental Symptoms Questionnaire scores and percentage of dehydration may indicate decreased signs and symptoms of heat strain in the G trial. Based on the NE trial performance, adequate pre-exercise hydration, even without glycerol, may limit the detrimental effects of dehydration. PMID:15173869
A method and technical equipment for an acute human trial to evaluate retinal implant technology
NASA Astrophysics Data System (ADS)
Hornig, Ralf; Laube, Thomas; Walter, Peter; Velikay-Parel, Michaela; Bornfeld, Norbert; Feucht, Matthias; Akguel, Harun; Rössler, Gernot; Alteheld, Nils; Lütke Notarp, Dietmar; Wyatt, John; Richard, Gisbert
2005-03-01
This paper reports on methods and technical equipment to investigate the epiretinal stimulation of the retina in blind human subjects in acute trials. Current is applied to the retina through a thin, flexible microcontact film (microelectrode array) with electrode diameters ranging from 50 to 360 µm. The film is mounted in a custom-designed surgical tool that is hand-held by the surgeon during stimulation. The eventual goal of the work is the development of a chronically implantable retinal prosthesis to restore a useful level of vision to patients who are blind with outer retinal degenerations, specifically retinitis pigmentosa and macular degeneration.
Redesigning TRACER trial after TRITON.
Serebruany, Victor L
2015-10-15
Designing of smart clinical trials is critical for regulatory approval and future drug utilization. Importantly, trial design should be reconsidered if the interim analyses suggest unexpected harm, or conflicting results were yielded from the other trials within the same therapeutic area. With regard to antiplatelet agents, the perfect example is redesigning of the ongoing PRoFESS trial by eliminating aspirin from clopidogrel arm after the earlier MATCH trial results became available. The goal was to aseess the unchanged TRACER trial design in light of the evidence yielded from the earlier completed TRITON trial. TRACER was designed as a triple versus dual antiplatelet trial in NSTEMI patients with no previous long-term outcome data supporting such aggressive strategy. TRITON data represented dual versus dual antiplatelet therapy, and became available before TRACER enrollment starts revealing prasugrel front-loaded early vascular benefit predominantly in STEMI patients with the growing over time bleeding and cancer risks. Moreover, large prasugrel NSTEMI TRITON cohort exhibited trend towards excess mortality in experimental arm warning against aggressive TRACER design. The long-term TRITON results in general, and especially in the NSTEMI patients challenge unchanged TRACER trial design. Applying dual, rather than triple antiplatelet therapy protocol modification should be considered in TRACER to minimize bleeding, cancer, and non-cardiovascular death risks. Copyright © 2015. Published by Elsevier Ireland Ltd.
Guetterman, Timothy C.; Fetters, Michael D.; Legocki, Laurie J.; Mawocha, Samkeliso; Barsan, William G.; Lewis, Roger J.; Berry, Donald A.; Meurer, William J.
2015-01-01
Context The context for this study was the Adaptive Designs Advancing Promising Treatments Into Trials (ADAPT-IT) project, which aimed to incorporate flexible adaptive designs into pivotal clinical trials and to conduct an assessment of the trial development process. Little research provides guidance to academic institutions in planning adaptive trials. Objectives The purpose of this qualitative study was to explore the perspectives and experiences of stakeholders as they reflected back about the interactive ADAPT-IT adaptive design development process, and to understand their perspectives regarding lessons learned about the design of the trials and trial development. Materials and methods We conducted semi-structured interviews with ten key stakeholders and observations of the process. We employed qualitative thematic text data analysis to reduce the data into themes about the ADAPT-IT project and adaptive clinical trials. Results The qualitative analysis revealed four themes: education of the project participants, how the process evolved with participant feedback, procedures that could enhance the development of other trials, and education of the broader research community. Discussion and conclusions While participants became more likely to consider flexible adaptive designs, additional education is needed to both understand the adaptive methodology and articulate it when planning trials. PMID:26622163
Tuffaha, Haitham W; Reynolds, Heather; Gordon, Louisa G; Rickard, Claire M; Scuffham, Paul A
2014-12-01
Value of information analysis has been proposed as an alternative to the standard hypothesis testing approach, which is based on type I and type II errors, in determining sample sizes for randomized clinical trials. However, in addition to sample size calculation, value of information analysis can optimize other aspects of research design such as possible comparator arms and alternative follow-up times, by considering trial designs that maximize the expected net benefit of research, which is the difference between the expected cost of the trial and the expected value of additional information. To apply value of information methods to the results of a pilot study on catheter securement devices to determine the optimal design of a future larger clinical trial. An economic evaluation was performed using data from a multi-arm randomized controlled pilot study comparing the efficacy of four types of catheter securement devices: standard polyurethane, tissue adhesive, bordered polyurethane and sutureless securement device. Probabilistic Monte Carlo simulation was used to characterize uncertainty surrounding the study results and to calculate the expected value of additional information. To guide the optimal future trial design, the expected costs and benefits of the alternative trial designs were estimated and compared. Analysis of the value of further information indicated that a randomized controlled trial on catheter securement devices is potentially worthwhile. Among the possible designs for the future trial, a four-arm study with 220 patients/arm would provide the highest expected net benefit corresponding to 130% return-on-investment. The initially considered design of 388 patients/arm, based on hypothesis testing calculations, would provide lower net benefit with return-on-investment of 79%. Cost-effectiveness and value of information analyses were based on the data from a single pilot trial which might affect the accuracy of our uncertainty estimation. Another limitation was that different follow-up durations for the larger trial were not evaluated. The value of information approach allows efficient trial design by maximizing the expected net benefit of additional research. This approach should be considered early in the design of randomized clinical trials. © The Author(s) 2014.
Boland, Mary Regina; Miotto, Riccardo; Gao, Junfeng; Weng, Chunhua
2013-01-01
Summary Background When standard therapies fail, clinical trials provide experimental treatment opportunities for patients with drug-resistant illnesses or terminal diseases. Clinical Trials can also provide free treatment and education for individuals who otherwise may not have access to such care. To find relevant clinical trials, patients often search online; however, they often encounter a significant barrier due to the large number of trials and in-effective indexing methods for reducing the trial search space. Objectives This study explores the feasibility of feature-based indexing, clustering, and search of clinical trials and informs designs to automate these processes. Methods We decomposed 80 randomly selected stage III breast cancer clinical trials into a vector of eligibility features, which were organized into a hierarchy. We clustered trials based on their eligibility feature similarities. In a simulated search process, manually selected features were used to generate specific eligibility questions to filter trials iteratively. Results We extracted 1,437 distinct eligibility features and achieved an inter-rater agreement of 0.73 for feature extraction for 37 frequent features occurring in more than 20 trials. Using all the 1,437 features we stratified the 80 trials into six clusters containing trials recruiting similar patients by patient-characteristic features, five clusters by disease-characteristic features, and two clusters by mixed features. Most of the features were mapped to one or more Unified Medical Language System (UMLS) concepts, demonstrating the utility of named entity recognition prior to mapping with the UMLS for automatic feature extraction. Conclusions It is feasible to develop feature-based indexing and clustering methods for clinical trials to identify trials with similar target populations and to improve trial search efficiency. PMID:23666475
Boland, M R; Miotto, R; Gao, J; Weng, C
2013-01-01
When standard therapies fail, clinical trials provide experimental treatment opportunities for patients with drug-resistant illnesses or terminal diseases. Clinical Trials can also provide free treatment and education for individuals who otherwise may not have access to such care. To find relevant clinical trials, patients often search online; however, they often encounter a significant barrier due to the large number of trials and in-effective indexing methods for reducing the trial search space. This study explores the feasibility of feature-based indexing, clustering, and search of clinical trials and informs designs to automate these processes. We decomposed 80 randomly selected stage III breast cancer clinical trials into a vector of eligibility features, which were organized into a hierarchy. We clustered trials based on their eligibility feature similarities. In a simulated search process, manually selected features were used to generate specific eligibility questions to filter trials iteratively. We extracted 1,437 distinct eligibility features and achieved an inter-rater agreement of 0.73 for feature extraction for 37 frequent features occurring in more than 20 trials. Using all the 1,437 features we stratified the 80 trials into six clusters containing trials recruiting similar patients by patient-characteristic features, five clusters by disease-characteristic features, and two clusters by mixed features. Most of the features were mapped to one or more Unified Medical Language System (UMLS) concepts, demonstrating the utility of named entity recognition prior to mapping with the UMLS for automatic feature extraction. It is feasible to develop feature-based indexing and clustering methods for clinical trials to identify trials with similar target populations and to improve trial search efficiency.
Systematic Review of Plant-Based Homeopathic Basic Research: An Update.
Ücker, Annekathrin; Baumgartner, Stephan; Sokol, Anezka; Huber, Roman; Doesburg, Paul; Jäger, Tim
2018-05-01
Plant-based test systems have been described as a useful tool for investigating possible effects of homeopathic preparations. The last reviews of this research field were published in 2009/2011. Due to recent developments in the field, an update is warranted. Publications on plant-based test systems were analysed with regard to publication quality, reproducibility and potential for further research. A literature search was conducted in online databases and specific journals, including publications from 2008 to 2017 dealing with plant-based test systems in homeopathic basic research. To be included, they had to contain statistical analysis and fulfil quality criteria according to a pre-defined manuscript information score (MIS). Publications scoring at least 5 points (maximum 10 points) were assumed to be adequate. They were analysed for the use of adequate controls, outcome and reproducibility. Seventy-four publications on plant-based test systems were found. Thirty-nine publications were either abstracts or proceedings of conferences and were excluded. From the remaining 35 publications, 26 reached a score of 5 or higher in the MIS. Adequate controls were used in 13 of these publications. All of them described specific effects of homeopathic preparations. The publication quality still varied: a substantial number of publications (23%) did not adequately document the methods used. Four reported on replication trials. One replication trial found effects of homeopathic preparations comparable to the original study. Three replication trials failed to confirm the original study but identified possible external influencing factors. Five publications described novel plant-based test systems. Eight trials used systematic negative control experiments to document test system stability. Regarding research design, future trials should implement adequate controls to identify specific effects of homeopathic preparations and include systematic negative control experiments. Further external and internal replication trials, and control of influencing factors, are needed to verify results. Standardised test systems should be developed. The Faculty of Homeopathy.
Fourcade, Lola; Boutron, Isabelle; Moher, David; Ronceray, Lucie; Baron, Gabriel; Ravaud, Philippe
2007-01-01
Objective: The aim of this study was to develop and evaluate a pedagogical tool to enhance the understanding of a checklist that evaluates reports of nonpharmacological trials (CLEAR NPT). Design: Paired randomised controlled trial. Participants: Clinicians and systematic reviewers. Interventions: We developed an Internet-based computer learning system (ICLS). This pedagogical tool used many examples from published randomised controlled trials to demonstrate the main coding difficulties encountered when using this checklist. Randomised participants received either a specific Web-based training with the ICLS (intervention group) or no specific training. Outcome measures: The primary outcome was the rate of correct answers compared to a criterion standard for coding a report of randomised controlled trials with the CLEAR NPT. Results: Between April and June 2006, 78 participants were randomly assigned to receive training with the ICLS (39) or no training (39). Participants trained by the ICLS did not differ from the control group in performance on the CLEAR NPT. The mean paired difference and corresponding 95% confidence interval was 0.5 (−5.1 to 6.1). The rate of correct answers did not differ between the two groups regardless of the CLEAR NPT item. Combining both groups, the rate of correct answers was high or items related to allocation sequence (79.5%), description of the intervention (82.0%), blinding of patients (79.5%), and follow-up schedule (83.3%). The rate of correct answers was low for items related to allocation concealment (46.1%), co-interventions (30.3%), blinding of outcome assessors (53.8%), specific measures to avoid ascertainment bias (28.6%), and intention-to-treat analysis (60.2%). Conclusions: Although we showed no difference in effect between the intervention and control groups, our results highlight the gap in knowledge and urgency for education on important aspects of trial conduct. PMID:17479163
ERIC Educational Resources Information Center
Hartung, Doreen; Hahlweg, Kurt
2011-01-01
Workplace Triple P (WPTP) is a group-based parenting skills training specifically designed to meet the needs of employed parents. Several randomized controlled trials have demonstrated the training's efficacy. This study examined possible mechanisms of change that account for the stress reduction effects of this parenting skills training at the…
A Body Image and Disordered Eating Intervention for Women in Midlife: A Randomized Controlled Trial
ERIC Educational Resources Information Center
McLean, Sian A.; Paxton, Susan J.; Wertheim, Eleanor H.
2011-01-01
Objective: This study examined the outcome of a body image and disordered eating intervention for midlife women. The intervention was specifically designed to address risk factors that are pertinent in midlife. Method: Participants were 61 women aged 30 to 60 years (M = 43.92, SD = 8.22) randomly assigned to intervention (n = 32) or (delayed…
Federal Register 2010, 2011, 2012, 2013, 2014
2011-04-21
... research study to assess the efficacy of a specific interactive Web-based teaching module in the field of... directly to the public to survey customers to determine the kind and quality of services they want and... controlled trial design that compares the group that receives educational exposure to the set of new...
ERIC Educational Resources Information Center
Herbert, Sharonne D.; Harvey, Elizabeth A.; Roberts, Jasmin L.; Wichowski, Kayla; Lugo-Candelas, Claudia I.
2013-01-01
The present study evaluated the effectiveness of a parent training and emotion socialization program designed specifically for hyperactive preschoolers. Participants were 31 preschool-aged children whose parents were randomly assigned to a parent training (PT) or waitlist (WL) control group. PT parents took part in a 14-week parenting program that…
USDA-ARS?s Scientific Manuscript database
Four evaluation plots were planted at the Michigan State University Saginaw Valley Bean and Beet Research Farm in 2008. Test 08BB01 was specifically designed to evaluate a number of non-traditional yield and physiological measures that had been suggested from earlier trials, in addition to the more ...
Vaccines for preventing enterotoxigenic Escherichia coli (ETEC) diarrhoea.
Ahmed, Tanvir; Bhuiyan, Taufiqur R; Zaman, K; Sinclair, David; Qadri, Firdausi
2013-07-05
Infection with enterotoxigenic Escherichia coli (ETEC) bacteria is a common cause of diarrhoea in adults and children in developing countries and is a major cause of 'travellers' diarrhoea' in people visiting or returning from endemic regions. A killed whole cell vaccine (Dukoral®), primarily designed and licensed to prevent cholera, has been recommended by some groups to prevent travellers' diarrhoea in people visiting endemic regions. This vaccine contains a recombinant B subunit of the cholera toxin that is antigenically similar to the heat labile toxin of ETEC. This review aims to evaluate the clinical efficacy of this vaccine and other vaccines designed specifically to protect people against diarrhoea caused by ETEC infection. To evaluate the efficacy, safety, and immunogenicity of vaccines for preventing ETEC diarrhoea. We searched the Cochrane Infectious Disease Group Specialized Register, the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, LILACS, and http://clinicaltrials.gov up to December 2012. Randomized controlled trials (RCTs) and quasi-RCTs comparing use of vaccines to prevent ETEC with use of no intervention, a control vaccine (either an inert vaccine or a vaccine normally given to prevent an unrelated infection), an alternative ETEC vaccine, or a different dose or schedule of the same ETEC vaccine in healthy adults and children living in endemic regions, intending to travel to endemic regions, or volunteering to receive an artificial challenge of ETEC bacteria. Two authors independently assessed each trial for eligibility and risk of bias. Two independent reviewers extracted data from the included studies and analyzed the data using Review Manager (RevMan) software. We reported outcomes as risk ratios (RR) with 95% confidence intervals (CI). We assessed the quality of the evidence using the GRADE approach. Twenty-four RCTs, including 53,247 participants, met the inclusion criteria. Four studies assessed the protective efficacy of oral cholera vaccines when used to prevent diarrhoea due to ETEC and seven studies assessed the protective efficacy of ETEC-specific vaccines. Of these 11 studies, seven studies presented efficacy data from field trials and four studies presented efficacy data from artificial challenge studies. An additional 13 trials contributed safety and immunological data only. Cholera vaccinesThe currently available, oral cholera killed whole cell vaccine (Dukoral®) was evaluated for protection of people against 'travellers' diarrhoea' in a single RCT in people arriving in Mexico from the USA. We did not identify any statistically significant effects on ETEC diarrhoea or all-cause diarrhoea (one trial, 502 participants, low quality evidence).Two earlier trials, one undertaken in an endemic population in Bangladesh and one undertaken in people travelling from Finland to Morocco, evaluated a precursor of this vaccine containing purified cholera toxin B subunit rather than the recombinant subunit in Dukoral®. Short term protective efficacy against ETEC diarrhoea was demonstrated, lasting for around three months (RR 0.43, 95% CI 0.26 to 0.71; two trials, 50,227 participants). This vaccine is no longer available. ETEC vaccinesAn ETEC-specific, killed whole cell vaccine, which also contains the recombinant cholera toxin B-subunit, was evaluated in people travelling from the USA to Mexico or Guatemala, and from Austria to Latin America, Africa, or Asia. We did not identify any statistically significant differences in ETEC-specific diarrhoea or all-cause diarrhoea (two trials, 799 participants), and the vaccine was associated with increased vomiting (RR 2.0, 95% CI 1.16 to 3.45; nine trials, 1528 participants). The other ETEC-specific vaccines in development have not yet demonstrated clinically important benefits. There is currently insufficient evidence from RCTs to support the use of the oral cholera vaccine Dukoral® for protecting travellers against ETEC diarrhoea. Further research is needed to develop safe and effective vaccines to provide both short and long-term protection against ETEC diarrhoea.
Improving Memory and Cognition in Individuals with Down Syndrome.
Rafii, Michael S
2016-07-01
Down syndrome (DS), often due to trisomy 21, is the most common genetic cause of intellectual disability (ID). In addition, virtually all individuals with DS develop the neuropathology of Alzheimer's disease (AD) by the age of 40 years and almost 60 % will manifest symptoms of AD dementia by the age of 65 years. Currently, there are no pharmacological treatments available for ID in individuals with DS and only limited symptomatic treatments for AD dementia. Advances in our understanding in both the molecular basis of ID and the pathogenesis of AD have created opportunities to study potential therapeutic targets. Recent studies in animal models of DS continue to provide a rational basis for translating specific compounds into human clinical trials. However, target and compound selection are only initial steps in the drug development pathway. Other necessary considerations include appropriate study designs to assess efficacy in the DS population, as well as operational aspects specifically tailored to assess cognition in this population. We discuss recent progress in the development of compounds for both ID and AD in individuals with DS, as well as concepts for the design and conduct of clinical trials with such compounds.
Fernández, Óscar; Arnal-García, Carmen; Arroyo-González, Rafael; Brieva, Lluís; Calles-Hernández, M Carmen; Casanova-Estruch, Bonaventura; Comabella, Manuel; de las Heras, Virginia; García-Merino, Juan A; Hernández-Pérez, Miguel A; Izquierdo, Guillermo; Matas, Elisabet; Meca-Lallana, José E; Mendibe-Bilbao, María del Mar; Muñoz-García, Delicias; Olascoaga, Javier; Oreja-Guevara, Celia; Prieto, José M; Ramió-Torrentà, Lluís; Rodríguez-Antigüedad, Alfredo; Saiz, Albert; Téllez, Nieves; Villar, Luisa M; Tintoré, Mar
2013-10-01
The most significant data presented at the 28th Congress of the European Committee for Treatment and Research in Multiple Sclerosis (ECTRIMS), held in France in October 2012, have been summarised in the fifth edition of the Post-ECTRIMS Experts Meeting, held in Madrid in October 2012. This led to the drafting of this review, which has been published in three parts. This third part of the Post-ECTRIMS review presents the findings from the latest studies conducted with disease-modifying treatments, more specifically with glatiramer acetate, laquinimod, ponesimod, BG-12, teriflunomide, daclizumab, natalizumab and secukinumab (AIN457). Likewise, we also address the reasons that justify the search for innovative treatments for multiple sclerosis, with antigen-specific therapy, cell therapy and therapy aimed at promoting remyelination being highlighted among other future therapeutic strategies. Access to new pharmacological agents and the complexity of the therapy of multiple sclerosis in the future will require new design strategies and directions in clinical trials, including the use of surrogate markers, new statistical applications, superiority, inferiority or equivalence clinical trials and adaptable designs.
Single-arm phase II trial design under parametric cure models.
Wu, Jianrong
2015-01-01
The current practice of designing single-arm phase II survival trials is limited under the exponential model. Trial design under the exponential model may not be appropriate when a portion of patients are cured. There is no literature available for designing single-arm phase II trials under the parametric cure model. In this paper, a test statistic is proposed, and a sample size formula is derived for designing single-arm phase II trials under a class of parametric cure models. Extensive simulations showed that the proposed test and sample size formula perform very well under different scenarios. Copyright © 2015 John Wiley & Sons, Ltd.
2011-01-01
Background Approximately one third of New Zealand children and young people are overweight or obese. A similar proportion (33%) do not meet recommendations for physical activity, and 70% do not meet recommendations for screen time. Increased time being sedentary is positively associated with being overweight. There are few family-based interventions aimed at reducing sedentary behavior in children. The aim of this trial is to determine the effects of a 24 week home-based, family oriented intervention to reduce sedentary screen time on children's body composition, sedentary behavior, physical activity, and diet. Methods/Design The study design is a pragmatic two-arm parallel randomized controlled trial. Two hundred and seventy overweight children aged 9-12 years and primary caregivers are being recruited. Participants are randomized to intervention (family-based screen time intervention) or control (no change). At the end of the study, the control group is offered the intervention content. Data collection is undertaken at baseline and 24 weeks. The primary trial outcome is child body mass index (BMI) and standardized body mass index (zBMI). Secondary outcomes are change from baseline to 24 weeks in child percentage body fat; waist circumference; self-reported average daily time spent in physical and sedentary activities; dietary intake; and enjoyment of physical activity and sedentary behavior. Secondary outcomes for the primary caregiver include change in BMI and self-reported physical activity. Discussion This study provides an excellent example of a theory-based, pragmatic, community-based trial targeting sedentary behavior in overweight children. The study has been specifically designed to allow for estimation of the consistency of effects on body composition for Māori (indigenous), Pacific and non-Māori/non-Pacific ethnic groups. If effective, this intervention is imminently scalable and could be integrated within existing weight management programs. Trial Registration ACTRN12611000164998 PMID:21718543
2012-01-01
Background Hand eczema has a one-year prevalence of approximately 10 % in the general Danish population. Often the disease becomes chronic with numerous implications for the individual’s daily life, occupation and quality of life. However, no guidelines of self-management recommendations beyond the acute stage are given. Self-management of the disease is pivotal and involves self-monitoring of the condition, medication adherence, and preventive behaviour. Interventions best to support the individual in this ongoing process need to be developed. Methods/design This paper describes the design of a randomised clinical trial to test a newly developed intervention of individual counselling versus conventional information. 300 patients consecutively referred to dermatologic treatment at two different settings are individually randomised to either the intervention programme, named ‘The Healthy Skin Clinic’ or to the control group. Block-wise randomisation according to setting and gender is carried out. The intervention offers a tool for self-monitoring; basic and specific individual counselling; the possibility of asynchronous communication with the intervention team; and an electronic patient dialogue forum. Primary outcome variable is objective assessment of the hand eczema severity performed at baseline prior to randomisation, and repeated at six months follow-up. Secondary outcome variables are dermatology related life quality and perceived global burden of disease. Discussion The trial aims at evaluating a newly developed guidance programme which is expected to support self-management of patients referred to dermatology treatment due to chronic hand eczema. The design of the protocol is pragmatic with blinding of neither participants nor the investigator. Thus, in the interpretation of the results, the investigator takes into account effects that may be attributed to actors of the interventions rather than the intervention per se as well of potential observer bias. Inclusion criterions are wide in order to increase transferability of the results. Trial registration The trial is registered in ClinicalTrials.Gov with registration number NCT01482663. PMID:22691871
Group sequential designs for stepped-wedge cluster randomised trials
Grayling, Michael J; Wason, James MS; Mander, Adrian P
2017-01-01
Background/Aims: The stepped-wedge cluster randomised trial design has received substantial attention in recent years. Although various extensions to the original design have been proposed, no guidance is available on the design of stepped-wedge cluster randomised trials with interim analyses. In an individually randomised trial setting, group sequential methods can provide notable efficiency gains and ethical benefits. We address this by discussing how established group sequential methodology can be adapted for stepped-wedge designs. Methods: Utilising the error spending approach to group sequential trial design, we detail the assumptions required for the determination of stepped-wedge cluster randomised trials with interim analyses. We consider early stopping for efficacy, futility, or efficacy and futility. We describe first how this can be done for any specified linear mixed model for data analysis. We then focus on one particular commonly utilised model and, using a recently completed stepped-wedge cluster randomised trial, compare the performance of several designs with interim analyses to the classical stepped-wedge design. Finally, the performance of a quantile substitution procedure for dealing with the case of unknown variance is explored. Results: We demonstrate that the incorporation of early stopping in stepped-wedge cluster randomised trial designs could reduce the expected sample size under the null and alternative hypotheses by up to 31% and 22%, respectively, with no cost to the trial’s type-I and type-II error rates. The use of restricted error maximum likelihood estimation was found to be more important than quantile substitution for controlling the type-I error rate. Conclusion: The addition of interim analyses into stepped-wedge cluster randomised trials could help guard against time-consuming trials conducted on poor performing treatments and also help expedite the implementation of efficacious treatments. In future, trialists should consider incorporating early stopping of some kind into stepped-wedge cluster randomised trials according to the needs of the particular trial. PMID:28653550
Patients' preferences for selection of endpoints in cardiovascular clinical trials.
Chow, Robert D; Wankhedkar, Kashmira P; Mete, Mihriye
2014-01-01
To reduce the duration and overall costs of cardiovascular trials, use of the combined endpoints in trial design has become commonplace. Though this methodology may serve the needs of investigators and trial sponsors, the preferences of patients or potential trial subjects in the trial design process has not been studied. To determine the preferences of patients in the design of cardiovascular trials. Participants were surveyed in a pilot study regarding preferences among various single endpoints commonly used in cardiovascular trials, preference for single vs. composite endpoints, and the likelihood of compliance with a heart medication if patients similar to them participated in the trial design process. One hundred adult English-speaking patients, 38% male, from a primary care ambulatory practice located in an urban setting. Among single endpoints, participants rated heart attack as significantly more important than death from other causes (4.53 vs. 3.69, p=0.004) on a scale of 1-6. Death from heart disease was rated as significantly more important than chest pain (4.73 vs. 2.47, p<0.001), angioplasty/PCI/CABG (4.73 vs. 2.43, p<0.001), and stroke (4.73 vs. 2.43, p<0.001). Participants also expressed a slight preference for combined endpoints over single endpoint (43% vs. 57%), incorporation of the opinions of the study patient population into the design of trials (48% vs. 41% for researchers), and a greater likelihood of medication compliance if patient preferences were considered during trial design (67% indicated a significant to major effect). Patients are able to make judgments and express preferences regarding trial design. They prefer that the opinions of the study population rather than the general population be incorporated into the design of the study. This novel approach to study design would not only incorporate patient preferences into medical decision making, but it also has the potential to improve compliance with cardiovascular medications.
Maxwell, Russell; Luksik, Andrew S; Garzon-Muvdi, Tomas; Lim, Michael
2017-06-01
Malignant gliomas, including glioblastoma and anaplastic astrocytoma, are the most frequent primary brain tumors and present with many treatment challenges. In this review, we discuss the potential of cellular- and viral-based immunotherapies in the treatment of malignant glioma, specifically focusing on dendritic cell vaccines, adoptive cell therapy, and oncolytic viruses. Diverse cellular- and viral-based strategies have been engineered and optimized to generate either a specific or broad antitumor immune response in malignant glioma. Due to their successes in the preclinical arena, many of these therapies have undergone phase I and II clinical testing. These early clinical trials have demonstrated the feasibility, safety, and efficacy of these immunotherapies. Dendritic cell vaccines, adoptive cell transfer, and oncolytic viruses may have a potential role in the treatment of malignant glioma. However, these modalities must be investigated in well-designed phase III trials to prove their efficacy.
Measurement and valuation of quality of life in economic appraisal of cancer treatment.
Uyl-de Groot, C A; Rutten, F F; Bonsel, G J
1994-01-01
In the economic evaluation (EE) of technologies in cancer treatment at least three endpoints are relevant: costs, survival and quality of life (QoL). This article is focused on QoL. EE requires the use of generic and valuation QoL instruments at a disease non-specific level, but the inclusion of cancer-specific instruments may be advisable, particularly for reasons of explanation if changes in dimensions are small or conflicting. Given the pros and cons of the available questionnaires, we advocate the use of the Nottingham Health Profile, the EuroQol and the Rotterdam Symptom Checklist. In our experience the QoL issue in EE linked with cancer trials is associated with practical problems like questionnaire composition, follow-up time, interviewing schedule, patients' compliance and doctors' acceptance. These problems are discussed and some practical guidelines for the design of QoL measurement in cancer trials are given.
Designing malaria vaccines to circumvent antigen variability✩
Ouattara, Amed; Barry, Alyssa E.; Dutta, Sheetij; Remarque, Edmond J.; Beeson, James G.; Plowe, Christopher V.
2016-01-01
Prospects for malaria eradication will be greatly enhanced by an effective vaccine, but parasite genetic diversity poses a major impediment to malaria vaccine efficacy. In recent pre-clinical and field trials, vaccines based on polymorphic Plasmodium falciparum antigens have shown efficacy only against homologous strains, raising the specter of allele-specific immunity such as that which plagues vaccines against influenza and HIV. The most advanced malaria vaccine, RTS,S, targets relatively conserved epitopes on the P. falciparum circumsporozoite protein. After more than 40 years of development and testing, RTS,S, has shown significant but modest efficacy against clinical malaria in phase 2 and 3 trials. Ongoing phase 2 studies of an irradiated sporozoite vaccine will ascertain whether the full protection against homologous experimental malaria challenge conferred by high doses of a whole organism vaccine can provide protection against diverse strains in the field. Here we review and evaluate approaches being taken to design broadly cross-protective malaria vaccines. PMID:26475447
Frye, Victoria; Henny, Kirk; Bonner, Sebastian; Williams, Kim; Bond, Keosha T; Hoover, Donald R; Lucy, Debbie; Greene, Emily; Koblin, Beryl A
2013-01-01
In the United States, heterosexual transmission is the second leading cause of HIV/AIDS, and two-thirds of all heterosexually acquired cases diagnosed between 2005 and 2008 occurred among African-Americans. Few HIV prevention interventions have been designed specifically for African-American heterosexual men not seeking clinical treatment. Here we report results of a single-arm intervention trial of a theory-based HIV prevention intervention designed to increase condom use, reduce concurrent partnering and increase HIV testing among heterosexually active African-American men living in high HIV prevalence areas of New York City. We tested our hypothesis using McNemar discordant pairs exact test for binary variables and paired t-tests for continuous variables. We observed statistically significant declines in mean number of total and new female partners, unprotected sex partners, and partner concurrency in both primary and nonprimary sex partnerships between baseline and 3 months postintervention.
Weissberg-Benchell, Jill; Rausch, Joseph; Iturralde, Esti; Jedraszko, Aneta; Hood, Korey
2016-01-01
Adolescents with type 1 diabetes have an increased risk for a variety of emotional and behavioral challenges as well as negative diabetes outcomes. This study was designed to compare the effectiveness of a depression-prevention, resilience promotion program with an advanced diabetes education program. Each program consisted of 9 group-based sessions. There were 264 adolescents enrolled in this multi-site randomized clinical trial. The primary outcomes were depressive symptoms and glycemic control; secondary outcomes included resilience skills, diabetes management and adherence, and diabetes-specific distress. The goal of the present paper is to describe the study design, the intervention, and the baseline characteristics of the sample. Preliminary data suggests that enrollment, randomization and retention were successful. Longitudinal follow-up and examination of mechanisms of action as they relate to psychosocial and glycemic outcomes will be explored in the future. PMID:27267154
Statistical challenges in a regulatory review of cardiovascular and CNS clinical trials.
Hung, H M James; Wang, Sue-Jane; Yang, Peiling; Jin, Kun; Lawrence, John; Kordzakhia, George; Massie, Tristan
2016-01-01
There are several challenging statistical problems identified in the regulatory review of large cardiovascular (CV) clinical outcome trials and central nervous system (CNS) trials. The problems can be common or distinct due to disease characteristics and the differences in trial design elements such as endpoints, trial duration, and trial size. In schizophrenia trials, heavy missing data is a big problem. In Alzheimer trials, the endpoints for assessing symptoms and the endpoints for assessing disease progression are essentially the same; it is difficult to construct a good trial design to evaluate a test drug for its ability to slow the disease progression. In CV trials, reliance on a composite endpoint with low event rate makes the trial size so large that it is infeasible to study multiple doses necessary to find the right dose for study patients. These are just a few typical problems. In the past decade, adaptive designs were increasingly used in these disease areas and some challenges occur with respect to that use. Based on our review experiences, group sequential designs (GSDs) have borne many successful stories in CV trials and are also increasingly used for developing treatments targeting CNS diseases. There is also a growing trend of using more advanced unblinded adaptive designs for producing efficacy evidence. Many statistical challenges with these kinds of adaptive designs have been identified through our experiences with the review of regulatory applications and are shared in this article.
2011-01-01
Background Dutch construction workers are offered periodic health examinations. This care can be improved by tailoring this workers health surveillance (WHS) to the demands of the job and adjust the preventive actions to the specific health risks of a worker in a particular job. To improve the quality of the WHS for construction workers and stimulate relevant job-specific preventive actions by the occupational physician, we have developed a job-specific WHS. The job-specific WHS consists of modules assessing both physical and psychological requirements. The selected measurement instruments chosen, are based on their appropriateness to measure the workers' capacity and health requirements. They include a questionnaire and biometrical tests, and physical performance tests that measure physical functional capabilities. Furthermore, our job-specific WHS provides occupational physicians with a protocol to increase the worker-behavioural effectiveness of their counselling and to stimulate job-specific preventive actions. The objective of this paper is to describe and clarify our study to evaluate the behavioural effects of this job-specific WHS on workers and occupational physicians. Methods/Design The ongoing study of bricklayers and supervisors is a nonrandomised trial to compare the outcome of an intervention (job-specific WHS) group (n = 206) with that of a control (WHS) group (n = 206). The study includes a three-month follow-up. The primary outcome measure is the proportion of participants who have undertaken one or more of the preventive actions advised by their occupational physician in the three months after attending the WHS. A process evaluation will be carried out to determine context, reach, dose delivered, dose received, fidelity, and satisfaction. The present study is in accordance with the TREND Statement. Discussion This study will allow an evaluation of the behaviour of both the workers and occupational physician regarding the preventive actions undertaken by them within the scope of a job-specific WHS. Trial registration NTR3012 PMID:21958019
Apovian, C M; Singer, M R; Campbell, W W; Bhasin, S; McCarthy, A C; Shah, M; Basaria, S; Moore, L L
2017-01-01
Nutrition impacts the development of sarcopenia and protein intake is an important modulator of skeletal muscle mass loss in older people. The Optimizing Protein Intake in Older Men with Mobility Limitation (OPTIMEN) Trial was designed to assess the independent and combined effects of higher protein intake and a promyogenic agent, testosterone, on lean body mass, muscle strength and physical function in older men with mobility disability. The purpose of this paper is to describe the experimental design and nutrition intervention, including techniques used by research dietitians to develop and deliver energy and protein-specific meals to the homes of community-dwelling participants. Strategies to enhance long-term dietary compliance are detailed. Randomized, double-blind, placebo-controlled six-month intervention trial. Participants were recruited from Boston MA USA and surrounding communities. Older men who were mobility-limited (Short Physical Performance Battery (SPPB) 3-10) and consuming less protein (<0.83 g/kg/day) were recruited for this study. Here we report the successful implementation of a double-blind, placebo-controlled, parallel group, randomized controlled trial with a 6-month intervention period among community-living men, age 65 years and older with a mobility limitation. A controlled feeding plan was used to deliver required energy intakes and prescribed protein quantities of 0.8 or 1.3 grams/kilogram/day (g/kg/d) in three meals plus snacks and supplements. A 2x2 factorial design was used to assess the effects of protein level alone and in combination with testosterone (vs. placebo) on changes in lean body mass (primary outcome), muscle strength, and physical function. A total of 154 men met the eligibility criteria; 112 completed a 2-week run-in period designed to evaluate compliance with the nutrition intervention. Of these, 92 subjects met compliance eligibility criteria and agreed to be randomized; 85% completed the full trial. The study successfully delivered three meals per day to subjects, with a high degree of compliance and subject satisfaction. Overall self-reported compliance rates were 80% and 93% for the meals and supplements, respectively. Details of compliance strategies are discussed. This community-based study design may serve as a model for longer-term nutritional interventions requiring monitoring of dietary compliance in a home-based feeding and supplementation trial.
The development of an innovative music therapy treatment method: trial competency through music.
Sammons, Andrew
2014-01-01
Competence to stand trial is necessary for a defendant in criminal adjudication. Recent estimates indicate that between 50,000 and 60,000 defendants in the United States raise the question of competence each year, with approximately 20 percent found incompetent to stand trial (IST). Most of these defendants are committed to an inpatient facility for competence restoration. Although psychopharmacological intervention is a critical component of restoration, as most defendants are found incompetent because of a psychotic disorder, many other modalities of treatment are used. Traditional treatment methods include the use of standardized testing and psychoeducational group sessions. This article discusses the development of an innovative intervention using music therapy. Music as the catalyst provides a forum in which psychiatric patients are engaged and observed within a structured environment designed to address both their factual and rational knowledge and abilities to assist their attorneys in their defense. Trial competency training through a specific music therapy method called Competency Through Music (CTM) is presented, including examples of how music can be used to educate patients and assess trial competence. © 2014 American Academy of Psychiatry and the Law.
Holbrook, Janet T; Kempen, John H; Prusakowski, Nancy A; Altaweel, Michael M; Jabs, Douglas A
2011-12-01
Randomized clinical trials (RCTs) are an important component of comparative effectiveness (CE) research because they are the optimal design for head-to-head comparisons of different treatment options. To describe decisions made in the design of the Multicenter Uveitis Steroid Treatment (MUST) Trial to ensure that the results would be widely generalizable. Review of design and implementation decisions and their rationale for the trial. The MUST Trial is a multicenter randomized controlled CE trial evaluating a novel local therapy (intraocular fluocinolone acetonide implant) versus the systemic therapy standard of care for noninfectious uveitis. Decisions made in protocol design in order to broaden enrollment included allowing patients with very poor vision and media opacity to enroll and including clinical sites outside the United States. The treatment protocol was designed to follow standard care. The primary outcome, visual acuity, is important to patients and can be evaluated in all eyes with uveitis. Other outcomes include patient-reported visual function, quality of life, and disease and treatment related complications. The trial population is too small for subgroup analyses that are of interest and the trial is being conducted at tertiary medical centers. CE trials require greater emphasis on generalizability than many RCTs but otherwise face similar challenges for design choices as any RCT. The increase in heterogeneity in patients and treatment required to ensure generalizability can be balanced with a rigorous approach to implementation, outcome assessment, and statistical design. This approach requires significant resources that may limit implementation in many RCTs, especially in clinical practice settings.
Ensuring Quality in AFRINEST and SATT
2013-01-01
Background: Three randomized open-label clinical trials [Simplified Antibiotic Therapy Trial (SATT) Bangladesh, SATT Pakistan and African Neonatal Sepsis Trial (AFRINEST)] were developed to test the equivalence of simplified antibiotic regimens compared with the standard regimen of 7 days of parenteral antibiotics. These trials were originally conceived and designed separately; subsequently, significant efforts were made to develop and implement a common protocol and approach. Previous articles in this supplement briefly describe the specific quality control methods used in the individual trials; this article presents additional information about the systematic approaches used to minimize threats to validity and ensure quality across the trials. Methods: A critical component of quality control for AFRINEST and SATT was striving to eliminate variation in clinical assessments and decisions regarding eligibility, enrollment and treatment outcomes. Ensuring appropriate and consistent clinical judgment was accomplished through standardized approaches applied across the trials, including training, assessment of clinical skills and refresher training. Standardized monitoring procedures were also applied across the trials, including routine (day-to-day) internal monitoring of performance and adherence to protocols, systematic external monitoring by funding agencies and external monitoring by experienced, independent trial monitors. A group of independent experts (Technical Steering Committee/Technical Advisory Group) provided regular monitoring and technical oversight for the trials. Conclusions: Harmonization of AFRINEST and SATT have helped to ensure consistency and quality of implementation, both internally and across the trials as a whole, thereby minimizing potential threats to the validity of the trials’ results. PMID:23945575
Saver, Jeffrey L; Jovin, Tudor G; Smith, Wade S; Albers, Gregory W; Baron, Jean-Claude; Boltze, Johannes; Broderick, Joseph P; Davis, Lisa A; Demchuk, Andrew M; DeSena, Salvatore; Fiehler, Jens; Gorelick, Philip B; Hacke, Werner; Holt, Bill; Jahan, Reza; Jing, Hui; Khatri, Pooja; Kidwell, Chelsea S; Lees, Kennedy R; Lev, Michael H; Liebeskind, David S; Luby, Marie; Lyden, Patrick; Megerian, J Thomas; Mocco, J; Muir, Keith W; Rowley, Howard A; Ruedy, Richard M; Savitz, Sean I; Sipelis, Vitas J; Shimp, Samuel K; Wechsler, Lawrence R; Wintermark, Max; Wu, Ona; Yavagal, Dileep R; Yoo, Albert J
2013-12-01
The goal of the Stroke Treatment Academic Industry Roundtable (STAIR) meetings is to advance the development of stroke therapies. At STAIR VIII, consensus recommendations were developed for clinical trial strategies to demonstrate the benefit of endovascular reperfusion therapies for acute ischemic stroke. Prospects for success with forthcoming endovascular trials are robust, because new neurothrombectomy devices have superior reperfusion efficacy compared with earlier-generation interventions. Specific recommendations are provided for trial designs in 3 populations: (1) patients undergoing intravenous fibrinolysis, (2) early patients ineligible for or having failed intravenous fibrinolysis, and (3) wake-up and other late-presenting patients. Among intravenous fibrinolysis-eligible patients, key principles are that CT or MRI confirmation of target arterial occlusions should precede randomization; endovascular intervention should be pursued with the greatest rapidity possible; and combined intravenous and neurothrombectomy therapy is more promising than neurothrombectomy alone. Among patients ineligible for or having failed intravenous fibrinolysis, scientific equipoise was affirmed and the need to randomize all eligible patients emphasized. Vessel imaging to confirm occlusion is mandatory, and infarct core and penumbral imaging is desirable in later time windows. Additional STAIR VIII recommendations include approaches to test multiple devices in a single trial, utility weighting of disability end points, and adaptive designs to delineate time and tissue injury thresholds at which benefits from intervention no longer accrue. Endovascular research priorities in acute ischemic stroke are to perform trials testing new, highly effective neuro thrombectomy devices rapidly deployed in patients confirmed to have target vessel occlusions.
Lin, Yunzhi
2016-08-15
Responder analysis is in common use in clinical trials, and has been described and endorsed in regulatory guidance documents, especially in trials where "soft" clinical endpoints such as rating scales are used. The procedure is useful, because responder rates can be understood more intuitively than a difference in means of rating scales. However, two major issues arise: 1) such dichotomized outcomes are inefficient in terms of using the information available and can seriously reduce the power of the study; and 2) the results of clinical trials depend considerably on the response cutoff chosen, yet in many disease areas there is no consensus as to what is the most appropriate cutoff. This article addresses these two issues, offering a novel approach for responder analysis that could both improve the power of responder analysis and explore different responder cutoffs if an agreed-upon common cutoff is not present. Specifically, we propose a statistically rigorous clinical trial design that pre-specifies multiple tests of responder rates between treatment groups based on a range of pre-specified responder cutoffs, and uses the minimum of the p-values for formal inference. The critical value for hypothesis testing comes from permutation distributions. Simulation studies are carried out to examine the finite sample performance of the proposed method. We demonstrate that the new method substantially improves the power of responder analysis, and in certain cases, yields power that is approaching the analysis using the original continuous (or ordinal) measure.
Expanding the Intertrial Interval During Extinction: Response Cessation and Recovery
Orinstein, Alyssa J.; Urcelay, Gonzalo P.; Miller, Ralph R.
2010-01-01
We examined trial spacing during extinction following a human contingency learning task. Specifically, we assessed if an expanding retrieval practice schedule (Bjork & Bjork, 1992, 2006), in which the spacing between extinction trials was progressively increased, would result in faster immediate extinction and less recovery from extinction than uniformly spaced extinction trials. We used an ABB vs. ABA renewal design and observed that, whereas the expanding group extinguished faster during extinction treatment, the expanding and constant groups showed the same level of extinction with an immediate test in the extinction context (ABB) and the two groups showed equivalent ABA renewal at test in the training context. We conclude that the faster extinction observed in the expanding groups could be misleading in clinical treatment, if the therapist used the absence of fear during extinction as the basis for terminating treatment. PMID:20171324
2011-01-01
Background Poor adherence to treatment is common in patients on hemodialysis which may increase risk for poor clinical outcomes and mortality. Self management interventions have been shown to be effective in improving compliance in other chronic populations. The aim of this trial is to evaluate the effectiveness of a recently developed group based self management intervention for hemodialysis patients compared to standard care. Methods/Design This is a multicentre parallel arm block randomized controlled trial (RCT) of a four session group self management intervention for hemodialysis patients delivered by health care professionals compared to standard care. A total of 176 consenting adults maintained on hemodialysis for a minimum of 6 months will be randomized to receive the self management intervention or standard care. Primary outcomes are biochemical markers of clinical status and adherence. Secondary outcomes include general health related quality of life, disease-specific quality of life, mood, self efficacy and self-reported adherence. Outcomes will be measured at baseline, immediately post-intervention and at 3 and 9 months post-intervention by an independent assessor and analysed on intention to treat principles with linear mixed-effects models across all time points. A qualitative component will examine which aspects of program participants found particularly useful and any barriers to change. Discussion The NKF-NUS intervention builds upon previous research emphasizing the importance of empowering patients in taking control of their treatment management. The trial design addresses weaknesses of previous research by use of an adequate sample size to detect clinically significant changes in biochemical markers, recruitment of a sufficiently large representative sample, a theory based intervention and careful assessment of both clinical and psychological endpoints at various follow up points. Inclusion of multiple dependent variables allows us to assess the broader impact on the intervention including both hard end points as well as patient reported outcomes. This program, if found to be effective, has the potential to be implemented within the existing renal services delivery model in Singapore, particularly as this is being delivered by health care professionals already working with hemodialysis patients in these settings who are specifically trained in facilitating self management in renal patients. Trial registration Current Controlled Trials ISRTN31434033 PMID:21272382
Uyei, Jennifer; Braithwaite, R Scott
2016-01-01
Despite the benefits of the placebo-controlled trial design, it is limited by its inability to quantify total benefits and harms. Such trials, for example, are not designed to detect an intervention's placebo or nocebo effects, which if detected could alter the benefit-to-harm balance and change a decision to adopt or reject an intervention. In this article, we explore scenarios in which alternative experimental trial designs, which differ in the type of control used, influence expected value across a range of pretest assumptions and study sample sizes. We developed a decision model to compare 3 trial designs and their implications for decision making: 2-arm placebo-controlled trial ("placebo-control"), 2-arm intervention v. do nothing trial ("null-control"), and an innovative 3-arm trial design: intervention v. do nothing v. placebo trial ("novel design"). Four scenarios were explored regarding particular attributes of a hypothetical intervention: 1) all benefits and no harm, 2) no biological effect, 3) only biological effects, and 4) surreptitious harm (no biological benefit or nocebo effect). Scenario 1: When sample sizes were very small, the null-control was preferred, but as sample sizes increased, expected value of all 3 designs converged. Scenario 2: The null-control was preferred regardless of sample size when the ratio of placebo to nocebo effect was >1; otherwise, the placebo-control was preferred. Scenario 3: When sample size was very small, the placebo-control was preferred when benefits outweighed harms, but the novel design was preferred when harms outweighed benefits. Scenario 4: The placebo-control was preferred when harms outweighed placebo benefits; otherwise, preference went to the null-control. Scenarios are hypothetical, study designs have not been tested in a real-world setting, blinding is not possible in all designs, and some may argue the novel design poses ethical concerns. We identified scenarios in which alternative experimental study designs would confer greater expected value than the placebo-controlled trial design. The likelihood and prevalence of such situations warrant further study. © The Author(s) 2015.
El-Damanawi, Ragada; Lee, Michael; Harris, Tess; Mader, Laura B; Bond, Simon; Pavey, Holly; Sandford, Richard N; Wilkinson, Ian B; Burrows, Alison; Woznowski, Przemyslaw; Ben-Shlomo, Yoav; Karet Frankl, Fiona E; Hiemstra, Thomas F
2018-01-01
Introduction Vasopressin stimulates cyst growth in autosomal dominant polycystic kidney disease (ADPKD) leading to enlarged kidneys, hypertension and renal failure. Vasopressin receptor blockade slows disease progression. Physiological suppression of vasopressin secretion through high water (HW) intake could achieve a similar effect, necessitating a definitive large-scale trial of HW intake in ADPKD. The objective of the DRINK trial is to answer the key design and feasibility questions required to deliver a successful definitive water intake trial. Methods and analysis We describe the design of a single-centre, open-label, prospective, randomised controlled trial. The "Determining feasibility of R andomisation to high vs. ad libitum water In take in Polycystic K idney Disease" (DRINK) trial aims to enrol 50 patients with ADPKD, over the age of 16 years with an estimated glomerular filtration rate (eGFR) ≥20 mL/min/1.73 m2. Participants will be randomised 1:1 to HW intake based on an individualised water intake prescription, or to ad libitum (AW) water intake. The HW group will aim for a dilute urine (urine osmolality ≤270 mOsm/kg) as a surrogate marker of vasopressin suppression, and those in the AW group will target more concentrated urine. Participants will have an 8-week treatment period, and will be seen at weeks 0, 2, 4 and 8, undergoing assessments of fluid status, renal function and serum and urine osmolalities. They will receive dietary advice, and self-monitor urine specific gravity and fluid intake. The trial employs smartphone technology to permit home monitoring and remote direct data capture. The primary feasibility end points are recruitment rate and separation between arms in measured urinary osmolality. Key secondary assessments include acceptability, adherence, health-related quality of life, acute effects of HW intake on measured (51Cr-EDTA) and eGFR and ADPKD-related pain. Ethics and dissemination Ethical approval was awarded by the East of England Essex Research Ethics Committee (16/EE/0026). The results of DRINK will be submitted to peer-reviewed journals, and presented to patients via the PKD Charity. Trial registration number NCT02933268 and ISCRTN16794957 PMID:29743334
Interpreting clinical trial results by deductive reasoning: In search of improved trial design.
Kurbel, Sven; Mihaljević, Slobodan
2017-10-01
Clinical trial results are often interpreted by inductive reasoning, in a trial design-limited manner, directed toward modifications of the current clinical practice. Deductive reasoning is an alternative in which results of relevant trials are combined in indisputable premises that lead to a conclusion easily testable in future trials. © 2017 WILEY Periodicals, Inc.
Specific barriers to the conduct of randomised clinical trials on medical devices.
Neugebauer, Edmund A M; Rath, Ana; Antoine, Sunya-Lee; Eikermann, Michaela; Seidel, Doerthe; Koenen, Carsten; Jacobs, Esther; Pieper, Dawid; Laville, Martine; Pitel, Séverine; Martinho, Cecilia; Djurisic, Snezana; Demotes-Mainard, Jacques; Kubiak, Christine; Bertele, Vittorio; Jakobsen, Janus C; Garattini, Silvio; Gluud, Christian
2017-09-13
Medical devices play an important role in the diagnosis, prevention, treatment and care of diseases. However, compared to pharmaceuticals, there is no rigorous formal regulation for demonstration of benefits and exclusion of harms to patients. The medical device industry argues that the classical evidence hierarchy cannot be applied for medical devices, as randomised clinical trials are impossible to perform. This article aims to identify the barriers for randomised clinical trials on medical devices. Systematic literature searches without meta-analysis and internal European Clinical Research Infrastructure Network (ECRIN) communications taking place during face-to-face meetings and telephone conferences from 2013 to 2017 within the context of the ECRIN Integrating Activity (ECRIN-IA) project. In addition to the barriers that exist for all trials, we identified three major barriers for randomised clinical trials on medical devices, namely: (1) randomisation, including timing of assessment, acceptability, blinding, choice of the comparator group and considerations on the learning curve; (2) difficulties in determining appropriate outcomes; and (3) the lack of scientific advice, regulations and transparency. The present review offers potential solutions to break down the barriers identified, and argues for applying the randomised clinical trial design when assessing the benefits and harms of medical devices.
Yao, N; Zeng, Q; Zhong, N X; Li, D X; Huang, L A; Shao, M Y; Ruan, H Y
2015-09-01
To investigate the willingness of Chinese female sex workers (FSWs) to participate (WTP) in a clinical trial of microbicides; to explore the potential hindrances and facilitating factors; and to provide support for future microbicide clinical trials by tailoring their design to better meet the specific needs of FSWs. Cross-sectional study. In total, 404 FSWs were investigated using structured questionnaires. Exploratory factor analysis and partial least squares path modelling were used to explore the correlations between several influencing factors and WTP. The WTP of FSWs enrolled in this study was high (53.47%, 216/404). Possible benefits from enrolment in the trial were positively associated with WTP, while concern about a hypothetical microbicide, potential physical harm, economic loss from participation, and fear of family or social isolation were negatively associated with WTP. FSWs are appropriate participants in microbicide clinical trials, and are likely to benefit from effective microbicides. In a microbicide clinical trial, it is imperative to ensure protection of the rights, dignity, safety, confidentiality and welfare of FSW participants. Copyright © 2015 The Royal Society for Public Health. Published by Elsevier Ltd. All rights reserved.
Quality of clinical trials: A moving target
Bhatt, Arun
2011-01-01
Quality of clinical trials depends on data integrity and subject protection. Globalization, outsourcing and increasing complexicity of clinical trials have made the target of achieving global quality challenging. The quality, as judged by regulatory inspections of the investigator sites, sponsors/contract research organizations and Institutional Review Board, has been of concern to the US Food and Drug Administration, as there has been hardly any change in frequency and nature of common deficiencies. To meet the regulatory expectations, the sponsors need to improve quality by developing systems with specific standards for each clinical trial process. The quality systems include: personnel roles and responsibilities, training, policies and procedures, quality assurance and auditing, document management, record retention, and reporting and corrective and preventive action. With an objective to improve quality, the FDA has planned new inspection approaches such as risk-based inspections, surveillance inspections, real-time oversight, and audit of sponsor quality systems. The FDA has partnered with Duke University for Clinical Trials Transformation Initiative, which will conduct research projects on design principles, data quality and quantity including monitoring, study start-up, and adverse event reporting. These recent initiatives will go a long way in improving quality of clinical trials. PMID:22145122
Osteoarthritis subpopulations and implications for clinical trial design
2011-01-01
Treatment guidelines for osteoarthritis have stressed the need for research on clinical predictors of response to different treatments. However, identifying such clinical predictors of response is less easy than it seems, and there is not a given classification of osteoarthritis subpopulations. This review article highlights the key methodical issues when analyzing and designing clinical studies to detect important subgroups with respect to treatment effect. In addition, we discuss the main osteoarthritis subpopulations and give examples of how specific treatment effects in these subpopulations have been assessed. PMID:21470393
Huhmann, Maureen B; Smith, Kristen N; Schwartz, Sherwyn L; Haller, Stacie K; Irvin, Sarah; Cohen, Sarah S
2016-01-01
The purpose of this clinical trial was to compare the glucose usage of two oral nutritional supplement (ONS) products and to assess whether a diabetes-specific formulation provides improved glucose stabilization and management compared with a standard formula. A total of 12 subjects with type 2 diabetes (7 males and 5 females) completed a randomized, cross-over design trial. Each subject consumed isocaloric amounts of either the standard ONS or the diabetes-specific formula ONS on different dates, 1 week apart. Glucose and insulin measures were recorded at baseline, and 10, 20, 30, 60, 90, 120, 150, 180, 210 and 240 min after the beverage was consumed and then used to calculate area under the curve (AUC) for each subject. The mean glucose AUC was lower in the diabetes-specific ONS group than in the standard group (p<0.0001), but there was not a significant difference observed for mean insulin AUC (p=0.068). A sensitivity analysis of the mean insulin AUC measures was performed by removing a potential outlier from the analysis, and this resulted in a significant difference between the groups (p=0.012). First-phase insulin measures and an insulinogenic index calculated for the beverages showed no significant differences. On the basis of the results of this trial of 12 subjects, the diabetes-specific ONS appears to provide better glucose maintenance in persons with type 2 diabetes when compared to the standard formula ONS. NCT02612675.
Bernstein, Judith A; Bernstein, Edward; Heeren, Timothy C
2010-09-01
Reductions in control group consumption over time that are possibly related to research design affect the impact of brief alcohol interventions (BAI) in clinical settings. We conducted a systematic review to identify research design factors that may contribute to control group change, strategies to limit these effects and implications for researchers. Studies with control group n > 30 were selected if they published baseline and outcome consumption data, conducted trials in clinical settings in Anglophone countries and did not censor gender or age. Among 38 studies cited in 20 reviews through October 2009, 16 met criteria (n = 31-370). In 54%, controls received alcohol specific handouts, advice and/or referral. Both the number and depth of assessments were highly variable. The percentage change in consumption ranged from-0.10 to-0.84 (mean-0.32), and effect size from 0.04 to 0.70 (mean 0.37). Published data were insufficient for meta-analysis. Researchers should consider strategies to reduce the impact of research design factors, such as procedures to enhance sample diversity, blind subjects to study purpose to limit social desirability bias, reduce the number and depth of instruments (assessment reactivity), and finally, analytic techniques to decrease the impact of outliers and regression to the mean. This review identifies problems with retrospective analysis of predictors of control group change, and underscores the need to design prospective studies to permit identification, quantification and adjustment for potential sources of bias in BAI trials.
Emery, C A; Roos, E M; Verhagen, E; Finch, C F; Bennell, K L; Story, B; Spindler, K; Kemp, J; Lohmander, L S
2015-05-01
The risk of post-traumatic osteoarthritis (PTOA) substantially increases following joint injury. Research efforts should focus on investigating the efficacy of preventative strategies in high quality randomized controlled trials (RCT). The objective of these OARSI RCT recommendations is to inform the design, conduct and analytical approaches to RCTs evaluating the preventative effect of joint injury prevention strategies. Recommendations regarding the design, conduct, and reporting of RCTs evaluating injury prevention interventions were established based on the consensus of nine researchers internationally with expertise in epidemiology, injury prevention and/or osteoarthritis (OA). Input and resultant consensus was established through teleconference, face to face and email correspondence over a 1 year period. Recommendations for injury prevention RCTs include context specific considerations regarding the research question, research design, study participants, randomization, baseline characteristics, intervention, outcome measurement, analysis, implementation, cost evaluation, reporting and future considerations including the impact on development of PTOA. Methodological recommendations for injury prevention RCTs are critical to informing evidence-based practice and policy decisions in health care, public health and the community. Recommendations regarding the interpretation and conduct of injury prevention RCTs will inform the highest level of evidence in the field. These recommendations will facilitate between study comparisons to inform best practice in injury prevention that will have the greatest public health impact. Copyright © 2015 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.
Sjoding, Michael W; Schoenfeld, David A; Brown, Samuel M; Hough, Catherine L; Yealy, Donald M; Moss, Marc; Angus, Derek C; Iwashyna, Theodore J
2017-01-01
After the sample size of a randomized clinical trial (RCT) is set by the power requirement of its primary endpoint, investigators select secondary endpoints while unable to further adjust sample size. How the sensitivity and specificity of an instrument used to measure these outcomes, together with their expected underlying event rates, affect an RCT's power to measure significant differences in these outcomes is poorly understood. Motivated by the design of an RCT of neuromuscular blockade in acute respiratory distress syndrome, we examined how power to detect a difference in secondary endpoints varies with the sensitivity and specificity of the instrument used to measure such outcomes. We derived a general formula and Stata code for calculating an RCT's power to detect differences in binary outcomes when such outcomes are measured with imperfect sensitivity and specificity. The formula informed the choice of instrument for measuring post-traumatic stress-like symptoms in the Reevaluation of Systemic Early Neuromuscular Blockade RCT ( www.clinicaltrials.gov identifier NCT02509078). On the basis of published sensitivities and specificities, the Impact of Events Scale-Revised was predicted to measure a 36% symptom rate, whereas the Post-Traumatic Stress Symptoms instrument was predicted to measure a 23% rate, if the true underlying rate of post-traumatic stress symptoms were 25%. Despite its lower sensitivity, the briefer Post-Traumatic Stress Symptoms instrument provided superior power to detect a difference in rates between trial arms, owing to its higher specificity. Examining instruments' power to detect differences in outcomes may guide their selection when multiple instruments exist, each with different sensitivities and specificities.
Schoenfeld, David A.; Brown, Samuel M.; Hough, Catherine L.; Yealy, Donald M.; Moss, Marc; Angus, Derek C.; Iwashyna, Theodore J.
2017-01-01
Rationale: After the sample size of a randomized clinical trial (RCT) is set by the power requirement of its primary endpoint, investigators select secondary endpoints while unable to further adjust sample size. How the sensitivity and specificity of an instrument used to measure these outcomes, together with their expected underlying event rates, affect an RCT’s power to measure significant differences in these outcomes is poorly understood. Objectives: Motivated by the design of an RCT of neuromuscular blockade in acute respiratory distress syndrome, we examined how power to detect a difference in secondary endpoints varies with the sensitivity and specificity of the instrument used to measure such outcomes. Methods: We derived a general formula and Stata code for calculating an RCT’s power to detect differences in binary outcomes when such outcomes are measured with imperfect sensitivity and specificity. The formula informed the choice of instrument for measuring post-traumatic stress–like symptoms in the Reevaluation of Systemic Early Neuromuscular Blockade RCT (www.clinicaltrials.gov identifier NCT02509078). Measurements and Main Results: On the basis of published sensitivities and specificities, the Impact of Events Scale-Revised was predicted to measure a 36% symptom rate, whereas the Post-Traumatic Stress Symptoms instrument was predicted to measure a 23% rate, if the true underlying rate of post-traumatic stress symptoms were 25%. Despite its lower sensitivity, the briefer Post-Traumatic Stress Symptoms instrument provided superior power to detect a difference in rates between trial arms, owing to its higher specificity. Conclusions: Examining instruments’ power to detect differences in outcomes may guide their selection when multiple instruments exist, each with different sensitivities and specificities. PMID:27788018
Lipman, Paula Darby; Loudon, Kirsty; Dluzak, Leanora; Moloney, Rachael; Messner, Donna; Stoney, Catherine M
2017-11-10
There continues to be debate about what constitutes a pragmatic trial and how it is distinguished from more traditional explanatory trials. The NIH Pragmatic Trials Collaborative Project, which includes five trials and a coordinating unit, has adopted the Pragmatic-Explanatory Continuum Indicator Summary (PRECIS-2) instrument. The purpose of the study was to collect PRECIS-2 ratings at two points in time to assess whether the tool was sensitive to change in trial design, and to explore with investigators the rationale for rating shifts. A mixed-methods design included sequential collection and analysis of quantitative data (PRECIS-2 ratings) and qualitative data. Ratings were collected at two annual, in-person project meetings, and subsequent interviews conducted with investigators were recorded, transcribed, and coded using NVivo 11 Pro for Windows. Rating shifts were coded as either (1) actual change (reflects a change in procedure or protocol), (2) primarily a rating shift reflecting rater variability, or (3) themes that reflect important concepts about the tool and/or pragmatic trial design. Based on PRECIS-2 ratings, each trial was highly pragmatic at the planning phase and remained so 1 year later in the early phases of trial implementation. Over half of the 45 paired ratings for the nine PRECIS-2 domains indicated a rating change from Time 1 to Time 2 (N = 24, 53%). Of the 24 rating changes, only three represented a true change in the design of the trial. Analysis of rationales for rating shifts identified critical themes associated with the tool or pragmatic trial design more generally. Each trial contributed one or more relevant comments, with Eligibility, Flexibility of Adherence, and Follow-up each accounting for more than one. PRECIS-2 has proved useful for "framing the conversation" about trial design among members of the Pragmatic Trials Collaborative Project. Our findings suggest that design elements assessed by the PRECIS-2 tool may represent mostly stable decisions. Overall, there has been a positive response to using PRECIS-2 to guide conversations around trial design, and the project's focus on the use of the tool by this group of early adopters has provided valuable feedback to inform future trainings on the tool.
Prostate biopsies assisted by comanipulated probe-holder: first in man.
Vitrani, Marie-Aude; Baumann, Michael; Reversat, David; Morel, Guillaume; Moreau-Gaudry, Alexandre; Mozer, Pierre
2016-06-01
A comanipulator for assisting endorectal prostate biopsies is evaluated through a first-in-man clinical trial. This lightweight system, based on conventional robotic components, possesses six degrees of freedom. It uses three electric motors and three brakes. It features a free mode, where its low friction and inertia allow for natural manipulation of the probe and a locked mode, exhibiting both a very low stiffness and a high steady-state precision. Clinical trials focusing on the free mode and the locked mode of the robot are presented. The objective was to evaluate the practical usability and performance of the robot during clinical procedures. A research protocol for a prospective randomized clinical trial has been designed. Its specific goal was to compare the accuracy of biopsies performed with and without the assistance of the comanipulator. The accuracy is compared between biopsies performed with and without the assistance of the comanipulator, across the 10 first patients included in the trial. Results show a statistically significant increase in the precision.
Do children with reading delay benefit from the use of personal FM systems in the classroom?
Purdy, Suzanne C; Smart, Jennifer L; Baily, Melissa; Sharma, Mridula
2009-12-01
FM systems have been used to compensate for poor signal-to-noise ratios in classrooms. This study evaluates benefits of a 6-week trial of personal FM systems used during the school day for children with reading delay aged 6-11 years, using a randomized control design. Teachers and children completed the LIFE-UK questionnaire. Test-retest reliability of the LIFE-UK children's version was confirmed in a separate group of 18 children from the same school. The 23 children in the FM group had significantly improved teacher ratings, and the children's ratings of classroom listening for difficult situations were significantly better after the trial. These changes did not occur for the 23 control-group children. Most children (92%) commented positively about the FM after the trial. It is likely that a longer FM trial or a specific reading intervention combined with FM will be required for the benefits of enhanced listening to affect performance on standardized reading tests.
Targeted polymeric nanoparticles for cancer gene therapy
Kim, Jayoung; Wilson, David R.; Zamboni, Camila G.; Green, Jordan J.
2015-01-01
In this article, advances in designing polymeric nanoparticles for targeted cancer gene therapy are reviewed. Characterization and evaluation of biomaterials, targeting ligands, and transcriptional elements are each discussed. Advances in biomaterials have driven improvements to nanoparticle stability and tissue targeting, conjugation of ligands to the surface of polymeric nanoparticles enable binding to specific cancer cells, and the design of transcriptional elements has enabled selective DNA expression specific to the cancer cells. Together, these features have improved the performance of polymeric nanoparticles as targeted non-viral gene delivery vectors to treat cancer. As polymeric nanoparticles can be designed to be biodegradable, non-toxic, and to have reduced immunogenicity and tumorigenicity compared to viral platforms, they have significant potential for clinical use. Results of polymeric gene therapy in clinical trials and future directions for the engineering of nanoparticle systems for targeted cancer gene therapy are also presented. PMID:26061296
NASA Astrophysics Data System (ADS)
Lançon, F.
2011-06-01
The Anti-ship Missile (ASM) threat to be faced by ships will become more diverse and difficult. Intelligence, rules of engagement constraints, fast reaction-time for effective softkill solution require specific tools to design Electronic Warfare (EW) systems and to integrate it onboard ship. SAGEM Company provides decoy launcher system [1] and its associated Naval Electronic Warfare Simulation tool (NEWS) to permit softkill effectiveness analysis for anti-ship missile defence. NEWS tool generates virtual environment for missile-ship engagement and counter-measure simulator over a wide spectrum: RF, IR, EO. It integrates EW Command & Control (EWC2) process which is implemented in decoy launcher system and performs Monte-Carlo batch processing to evaluate softkill effectiveness in different engagement situations. NEWS is designed to allow immediate EWC2 process integration from simulation to real decoy launcher system. By design, it allows the final operator to be able to program, test and integrate its own EWC2 module and EW library onboard, so intelligence of each user is protected and evolution of threat can be taken into account through EW library update. The objectives of NEWS tool are also to define a methodology for trial definition and trial data reduction. Growth potential would permit to design new concept for EWC2 programmability and real time effectiveness estimation in EW system. This tool can also be used for operator training purpose. This paper presents the architecture design, the softkill programmability facility concept and the flexibility for onboard integration on ship. The concept of this operationally focused simulation, which is to use only one tool for design, development, trial validation and operational use, will be demonstrated.
Bayesian adaptive phase II screening design for combination trials.
Cai, Chunyan; Yuan, Ying; Johnson, Valen E
2013-01-01
Trials of combination therapies for the treatment of cancer are playing an increasingly important role in the battle against this disease. To more efficiently handle the large number of combination therapies that must be tested, we propose a novel Bayesian phase II adaptive screening design to simultaneously select among possible treatment combinations involving multiple agents. Our design is based on formulating the selection procedure as a Bayesian hypothesis testing problem in which the superiority of each treatment combination is equated to a single hypothesis. During the trial conduct, we use the current values of the posterior probabilities of all hypotheses to adaptively allocate patients to treatment combinations. Simulation studies show that the proposed design substantially outperforms the conventional multiarm balanced factorial trial design. The proposed design yields a significantly higher probability for selecting the best treatment while allocating substantially more patients to efficacious treatments. The proposed design is most appropriate for the trials combining multiple agents and screening out the efficacious combination to be further investigated. The proposed Bayesian adaptive phase II screening design substantially outperformed the conventional complete factorial design. Our design allocates more patients to better treatments while providing higher power to identify the best treatment at the end of the trial.
2011-01-01
Background Crew resource management (CRM) has the potential to enhance patient safety in intensive care units (ICU) by improving the use of non-technical skills. However, CRM evaluation studies in health care are inconclusive with regard to the effect of this training on behaviour and organizational outcomes, due to weak study designs and the scarce use of direct observations. Therefore, the aim of this study is to determine the effectiveness and cost-effectiveness of CRM training on attitude, behaviour and organization after one year, using a multi-method approach and matched control units. The purpose of the present article is to describe the study protocol and the underlying choices of this evaluation study of CRM in the ICU in detail. Methods/Design Six ICUs participated in a paired controlled trial, with one pre-test and two post test measurements (respectively three months and one year after the training). Three ICUs were trained and compared to matched control ICUs. The 2-day classroom-based training was delivered to multidisciplinary groups. Typical CRM topics on the individual, team and organizational level were discussed, such as situational awareness, leadership and communication. All levels of Kirkpatrick's evaluation framework (reaction, learning, behaviour and organisation) were assessed using questionnaires, direct observations, interviews and routine ICU administration data. Discussion It is expected that the CRM training acts as a generic intervention that stimulates specific interventions. Besides effectiveness and cost-effectiveness, the assessment of the barriers and facilitators will provide insight in the implementation process of CRM. Trial registration Netherlands Trial Register (NTR): NTR1976 PMID:22073981
Bekelman, David B; Allen, Larry A; Peterson, Jamie; Hattler, Brack; Havranek, Edward P; Fairclough, Diane L; McBryde, Connor F; Meek, Paula M
2016-11-01
While contemporary heart failure management has led to some improvements in morbidity and mortality, patients continue to report poor health status (i.e., burdensome symptoms, impaired function, and poor quality of life). The Collaborative Care to Alleviate Symptoms and Adjust to Illness (CASA) trial is a NIH-funded, three-site, randomized clinical trial that examines the effect of the CASA intervention compared to usual care on the primary outcome of patient-reported health status at 6months in patients with heart failure and poor health status. The CASA intervention involves a nurse who works with patients to treat symptoms (e.g., shortness of breath, fatigue, pain) using disease-specific and palliative approaches, and a social worker who provides psychosocial care targeting depression and adjustment to illness. The intervention uses a collaborative care team model of health care delivery and is structured and primarily phone-based to enhance reproducibility and scalability. This article describes the rationale and design of the CASA trial, including several decision points: (1) how to design a patient-centered intervention to improve health status; (2) how to structure the intervention so that it is reproducible and scalable; and (3) how to systematically identify outpatients with heart failure most likely to need and benefit from the intervention. The results should provide valuable information to providers and health systems about the use of team care to manage symptoms and provide psychosocial care in chronic illness. Published by Elsevier Inc.
Hilgers, Ralf-Dieter; Bogdan, Malgorzata; Burman, Carl-Fredrik; Dette, Holger; Karlsson, Mats; König, Franz; Male, Christoph; Mentré, France; Molenberghs, Geert; Senn, Stephen
2018-05-11
IDeAl (Integrated designs and analysis of small population clinical trials) is an EU funded project developing new statistical design and analysis methodologies for clinical trials in small population groups. Here we provide an overview of IDeAl findings and give recommendations to applied researchers. The description of the findings is broken down by the nine scientific IDeAl work packages and summarizes results from the project's more than 60 publications to date in peer reviewed journals. In addition, we applied text mining to evaluate the publications and the IDeAl work packages' output in relation to the design and analysis terms derived from in the IRDiRC task force report on small population clinical trials. The results are summarized, describing the developments from an applied viewpoint. The main result presented here are 33 practical recommendations drawn from the work, giving researchers a comprehensive guidance to the improved methodology. In particular, the findings will help design and analyse efficient clinical trials in rare diseases with limited number of patients available. We developed a network representation relating the hot topics developed by the IRDiRC task force on small population clinical trials to IDeAl's work as well as relating important methodologies by IDeAl's definition necessary to consider in design and analysis of small-population clinical trials. These network representation establish a new perspective on design and analysis of small-population clinical trials. IDeAl has provided a huge number of options to refine the statistical methodology for small-population clinical trials from various perspectives. A total of 33 recommendations developed and related to the work packages help the researcher to design small population clinical trial. The route to improvements is displayed in IDeAl-network representing important statistical methodological skills necessary to design and analysis of small-population clinical trials. The methods are ready for use.
Wang, Zihao; Lorin, Clarisse; Koutsoukos, Marguerite; Franco, David; Bayat, Babak; Zhang, Ying; Carfi, Andrea; Barnett, Susan W.; Porter, Frederick
2016-01-01
Two HIV-1 subtype C gp120 protein candidates were the selected antigens for several experimental vaccine regimens now under evaluation in HVTN 100 Phase I/II clinical trial aiming to support the start of the HVTN 702 Phase IIb/III trial in southern Africa, which is designed to confirm and extend the partial protection seen against HIV-1 infection in the RV144 Thai trial. Here, we report the comprehensive physicochemical characterization of the gp120 reference materials that are representative of the clinical trial materials. Gp120 proteins were stably expressed in Chinese Hamster Ovary (CHO) cells and subsequently purified and formulated. A panel of analytical techniques was used to characterize the physicochemical properties of the two protein molecules. When formulated in the AS01 Adjuvant System, the bivalent subtype C gp120 antigens elicited 1086.C- and TV1.C-specific binding antibody and CD4+ T cell responses in mice. All the characteristics were highly representative of the Clinical Trial Materials (CTM). Data from this report demonstrate the immunogenicity of the gp120 antigens, provide comprehensive characterization of the molecules, set the benchmark for assessment of current and future CTM lots, and lay the physicochemical groundwork for interpretation of future clinical trial data. PMID:27187483
Design of a cluster-randomized minority recruitment trial: RECRUIT.
Tilley, Barbara C; Mainous, Arch G; Smith, Daniel W; McKee, M Diane; Amorrortu, Rossybelle P; Alvidrez, Jennifer; Diaz, Vanessa; Ford, Marvella E; Fernandez, Maria E; Hauser, Robert A; Singer, Carlos; Landa, Veronica; Trevino, Aron; DeSantis, Stacia M; Zhang, Yefei; Daniels, Elvan; Tabor, Derrick; Vernon, Sally W
2017-06-01
Racial/ethnic minority groups remain underrepresented in clinical trials. Many strategies to increase minority recruitment focus on minority communities and emphasize common diseases such as hypertension. Scant literature focuses on minority recruitment to trials of less common conditions, often conducted in specialty clinics and dependent on physician referrals. We identified trust/mistrust of specialist physician investigators and institutions conducting medical research and consequent participant reluctance to participate in clinical trials as key-shared barriers across racial/ethnic groups. We developed a trust-based continuous quality improvement intervention to build trust between specialist physician investigators and community minority-serving physicians and ultimately potential trial participants. To avoid the inherent biases of non-randomized studies, we evaluated the intervention in the national Randomized Recruitment Intervention Trial (RECRUIT). This report presents the design of RECRUIT. Specialty clinic follow-up continues through April 2017. We hypothesized that specialist physician investigators and coordinators trained in the trust-based continuous quality improvement intervention would enroll a greater proportion of minority participants in their specialty clinics than specialist physician investigators in control specialty clinics. Specialty clinic was the unit of randomization. Using continuous quality improvement, the specialist physician investigators and coordinators tailored recruitment approaches to their specialty clinic characteristics and populations. Primary analyses were adjusted for clustering by specialty clinic within parent trial and matching covariates. RECRUIT was implemented in four multi-site clinical trials (parent trials) supported by three National Institutes of Health institutes and included 50 associated specialty clinics from these parent trials. Using current data, we have 88% power or greater to detect a 0.15 or greater difference from the currently observed control proportion adjusting for clustering. We detected no differences in baseline matching criteria between intervention and control specialty clinics (all p values > 0.17). RECRUIT was the first multi-site randomized control trial to examine the effectiveness of a trust-based continuous quality improvement intervention to increase minority recruitment into clinical trials. RECRUIT's innovations included its focus on building trust between specialist investigators and minority-serving physicians, the use of continuous quality improvement to tailor the intervention to each specialty clinic's specific racial/ethnic populations and barriers to minority recruitment, and the use of specialty clinics from more than one parent multi-site trial to increase generalizability. The effectiveness of the RECRUIT intervention will be determined after the completion of trial data collection and planned analyses.
Mistry, Pankaj; Dunn, Janet A; Marshall, Andrea
2017-07-18
The application of adaptive design methodology within a clinical trial setting is becoming increasingly popular. However the application of these methods within trials is not being reported as adaptive designs hence making it more difficult to capture the emerging use of these designs. Within this review, we aim to understand how adaptive design methodology is being reported, whether these methods are explicitly stated as an 'adaptive design' or if it has to be inferred and to identify whether these methods are applied prospectively or concurrently. Three databases; Embase, Ovid and PubMed were chosen to conduct the literature search. The inclusion criteria for the review were phase II, phase III and phase II/III randomised controlled trials within the field of Oncology that published trial results in 2015. A variety of search terms related to adaptive designs were used. A total of 734 results were identified, after screening 54 were eligible. Adaptive designs were more commonly applied in phase III confirmatory trials. The majority of the papers performed an interim analysis, which included some sort of stopping criteria. Additionally only two papers explicitly stated the term 'adaptive design' and therefore for most of the papers, it had to be inferred that adaptive methods was applied. Sixty-five applications of adaptive design methods were applied, from which the most common method was an adaptation using group sequential methods. This review indicated that the reporting of adaptive design methodology within clinical trials needs improving. The proposed extension to the current CONSORT 2010 guidelines could help capture adaptive design methods. Furthermore provide an essential aid to those involved with clinical trials.
Sunderland, John J; Christian, Paul E
2015-01-01
The Clinical Trials Network (CTN) of the Society of Nuclear Medicine and Molecular Imaging (SNMMI) operates a PET/CT phantom imaging program using the CTN's oncology clinical simulator phantom, designed to validate scanners at sites that wish to participate in oncology clinical trials. Since its inception in 2008, the CTN has collected 406 well-characterized phantom datasets from 237 scanners at 170 imaging sites covering the spectrum of commercially available PET/CT systems. The combined and collated phantom data describe a global profile of quantitative performance and variability of PET/CT data used in both clinical practice and clinical trials. Individual sites filled and imaged the CTN oncology PET phantom according to detailed instructions. Standard clinical reconstructions were requested and submitted. The phantom itself contains uniform regions suitable for scanner calibration assessment, lung fields, and 6 hot spheric lesions with diameters ranging from 7 to 20 mm at a 4:1 contrast ratio with primary background. The CTN Phantom Imaging Core evaluated the quality of the phantom fill and imaging and measured background standardized uptake values to assess scanner calibration and maximum standardized uptake values of all 6 lesions to review quantitative performance. Scanner make-and-model-specific measurements were pooled and then subdivided by reconstruction to create scanner-specific quantitative profiles. Different makes and models of scanners predictably demonstrated different quantitative performance profiles including, in some cases, small calibration bias. Differences in site-specific reconstruction parameters increased the quantitative variability among similar scanners, with postreconstruction smoothing filters being the most influential parameter. Quantitative assessment of this intrascanner variability over this large collection of phantom data gives, for the first time, estimates of reconstruction variance introduced into trials from allowing trial sites to use their preferred reconstruction methodologies. Predictably, time-of-flight-enabled scanners exhibited less size-based partial-volume bias than non-time-of-flight scanners. The CTN scanner validation experience over the past 5 y has generated a rich, well-curated phantom dataset from which PET/CT make-and-model and reconstruction-dependent quantitative behaviors were characterized for the purposes of understanding and estimating scanner-based variances in clinical trials. These results should make it possible to identify and recommend make-and-model-specific reconstruction strategies to minimize measurement variability in cancer clinical trials. © 2015 by the Society of Nuclear Medicine and Molecular Imaging, Inc.
Effects of environmental design on patient outcome: a systematic review.
Laursen, Jannie; Danielsen, Anne; Rosenberg, Jacob
2014-01-01
The aim of this systematic review was to assess how inpatients were affected by the built environment design during their hospitalization. Over the last decade, the healthcare system has become increasingly aware of how focus on healthcare environment might affect patient satisfaction. The focus on environmental design has become a field with great potential because of its possible impact on cost control while improving quality of care. A systematic literature search was conducted to identify current and past studies about evidence-based healthcare design. The following databases were searched: Medline/PubMed, Cinahl, and Embase. Inclusion criteria were randomized clinical trials (RCTs) investigating the effect of built environment design interventions such as music, natural murals, and plants in relation to patients' health outcome. Built environment design aspects such as audio environment and visual environment had a positive influence on patients' health outcomes. Specifically the studies indicated a decrease in patients' anxiety, pain, and stress levels when exposed to certain built environment design interventions. The built environment, especially specific audio and visual aspects, seems to play an important role in patients' outcomes, making hospitals a better healing environment for patients. Built environment, evidence-based design, healing environments, hospitals, literature review.
How individual participant data meta-analyses have influenced trial design, conduct, and analysis.
Tierney, Jayne F; Pignon, Jean-Pierre; Gueffyier, Francois; Clarke, Mike; Askie, Lisa; Vale, Claire L; Burdett, Sarah
2015-11-01
To demonstrate how individual participant data (IPD) meta-analyses have impacted directly on the design and conduct of trials and highlight other advantages IPD might offer. Potential examples of the impact of IPD meta-analyses on trials were identified at an international workshop, attended by individuals with experience in the conduct of IPD meta-analyses and knowledge of trials in their respective clinical areas. Experts in the field who did not attend were asked to provide any further examples. We then examined relevant trial protocols, publications, and Web sites to verify the impacts of the IPD meta-analyses. A subgroup of workshop attendees sought further examples and identified other aspects of trial design and conduct that may inform IPD meta-analyses. We identified 52 examples of IPD meta-analyses thought to have had a direct impact on the design or conduct of trials. After screening relevant trial protocols and publications, we identified 28 instances where IPD meta-analyses had clearly impacted on trials. They have influenced the selection of comparators and participants, sample size calculations, analysis and interpretation of subsequent trials, and the conduct and analysis of ongoing trials, sometimes in ways that would not possible with systematic reviews of aggregate data. We identified additional potential ways that IPD meta-analyses could be used to influence trials. IPD meta-analysis could be better used to inform the design, conduct, analysis, and interpretation of trials. Crown Copyright © 2015. Published by Elsevier Inc. All rights reserved.
Poutanen, Kaisa S; Dussort, Pierre; Erkner, Alfrun; Fiszman, Susana; Karnik, Kavita; Kristensen, Mette; Marsaux, Cyril Fm; Miquel-Kergoat, Sophie; Pentikäinen, Saara P; Putz, Peter; Slavin, Joanne L; Steinert, Robert E; Mela, David J
2017-09-01
Background: Many intervention studies have tested the effect of dietary fibers (DFs) on appetite-related outcomes, with inconsistent results. However, DFs comprise a wide range of compounds with diverse properties, and the specific contribution of these to appetite control is not well characterized. Objective: The influence of specific DF characteristics [i.e., viscosity, gel-forming capacity, fermentability, or molecular weight (MW)] on appetite-related outcomes was assessed in healthy humans. Design: Controlled human intervention trials that tested the effects of well-characterized DFs on appetite ratings or energy intake were identified from a systematic search of literature. Studies were included only if they reported 1 ) DF name and origin and 2 ) data on viscosity, gelling properties, fermentability, or MW of the DF materials or DF-containing matrixes. Results: A high proportion of the potentially relevant literature was excluded because of lack of adequate DF characterization. In total, 49 articles that met these criteria were identified, which reported 90 comparisons of various DFs in foods, beverages, or supplements in acute or sustained-exposure trials. In 51 of the 90 comparisons, the DF-containing material of interest was efficacious for ≥1 appetite-related outcome. Reported differences in material viscosity, MW, or fermentability did not clearly correspond to differences in efficacy, whereas gel-forming DF sources were consistently efficacious (but with very few comparisons). Conclusions: The overall inconsistent relations of DF properties with respect to efficacy may reflect variation in measurement methodology, nature of the DF preparation and matrix, and study designs. Methods of DF characterization, incorporation, and study design are too inconsistent to allow generalized conclusions about the effects of DF properties on appetite and preclude the development of reliable, predictive, structure-function relations. Improved standards for characterization and reporting of DF sources and DF-containing materials are strongly recommended for future studies on the effects of DF on human physiology. This trial was registered at http://www.crd.york.ac.uk/PROSPERO as CRD42015015336. © 2017 American Society for Nutrition.
Connor, Jason T; Elm, Jordan J; Broglio, Kristine R
2013-08-01
We present a novel Bayesian adaptive comparative effectiveness trial comparing three treatments for status epilepticus that uses adaptive randomization with potential early stopping. The trial will enroll 720 unique patients in emergency departments and uses a Bayesian adaptive design. The trial design is compared to a trial without adaptive randomization and produces an efficient trial in which a higher proportion of patients are likely to be randomized to the most effective treatment arm while generally using fewer total patients and offers higher power than an analogous trial with fixed randomization when identifying a superior treatment. When one treatment is superior to the other two, the trial design provides better patient care, higher power, and a lower expected sample size. Copyright © 2013 Elsevier Inc. All rights reserved.
Simon, S; Higginson, I J
2009-01-01
Hospital palliative care teams (HPCTs) are well established as multi-professional services to provide palliative care in an acute hospital setting and are increasing in number. However, there is still limited evaluation of them, in terms of efficacy and effectiveness. The gold standard method of evaluation is a randomised control trial, but because of methodological (e.g., randomisation), ethical and practical difficulties such trials are often not possible. HPCT is a complex intervention, and the specific situation in palliative care makes it challenging to evaluate (e.g., distress and cognitive impairment of patients). The quasi-experimental before-after study design has the advantage of enabling an experimental character without randomisation. But this has other weaknesses and is prone to bias, for example, temporal trends and selection bias. As for every study design, avoidance and minimisation of bias is important to improve validity. Therefore, strategies of selecting an appropriate control group or time series and applying valid outcomes and measurement tools help reducing bias and strengthen the methods. Special attention is needed to plan and define the design and applied method.
Karkar, Ravi; Schroeder, Jessica; Epstein, Daniel A; Pina, Laura R; Scofield, Jeffrey; Fogarty, James; Kientz, Julie A; Munson, Sean A; Vilardaga, Roger; Zia, Jasmine
2017-05-02
Diagnostic self-tracking, the recording of personal information to diagnose or manage a health condition, is a common practice, especially for people with chronic conditions. Unfortunately, many who attempt diagnostic self-tracking have trouble accomplishing their goals. People often lack knowledge and skills needed to design and conduct scientifically rigorous experiments, and current tools provide little support. To address these shortcomings and explore opportunities for diagnostic self-tracking, we designed, developed, and evaluated a mobile app that applies a self-experimentation framework to support patients suffering from irritable bowel syndrome (IBS) in identifying their personal food triggers. TummyTrials aids a person in designing, executing, and analyzing self-experiments to evaluate whether a specific food triggers their symptoms. We examined the feasibility of this approach in a field study with 15 IBS patients, finding that participants could use the tool to reliably undergo a self-experiment. However, we also discovered an underlying tension between scientific validity and the lived experience of self-experimentation. We discuss challenges of applying clinical research methods in everyday life, motivating a need for the design of self-experimentation systems to balance rigor with the uncertainties of everyday life.
Aoun, Samar M; Nekolaichuk, Cheryl
2014-12-01
The adoption of evidence-based hierarchies and research methods from other disciplines may not completely translate to complex palliative care settings. The heterogeneity of the palliative care population, complexity of clinical presentations, and fluctuating health states present significant research challenges. The aim of this narrative review was to explore the debate about the use of current evidence-based approaches for conducting research, such as randomized controlled trials and other study designs, in palliative care, and more specifically to (1) describe key myths about palliative care research; (2) highlight substantive challenges of conducting palliative care research, using case illustrations; and (3) propose specific strategies to address some of these challenges. Myths about research in palliative care revolve around evidence hierarchies, sample heterogeneity, random assignment, participant burden, and measurement issues. Challenges arise because of the complex physical, psychological, existential, and spiritual problems faced by patients, families, and service providers. These challenges can be organized according to six general domains: patient, system/organization, context/setting, study design, research team, and ethics. A number of approaches for dealing with challenges in conducting research fall into five separate domains: study design, sampling, conceptual, statistical, and measures and outcomes. Although randomized controlled trials have their place whenever possible, alternative designs may offer more feasible research protocols that can be successfully implemented in palliative care. Therefore, this article highlights "outside the box" approaches that would benefit both clinicians and researchers in the palliative care field. Ultimately, the selection of research designs is dependent on a clearly articulated research question, which drives the research process. Copyright © 2014 American Academy of Hospice and Palliative Medicine. Published by Elsevier Inc. All rights reserved.
Emerging innovations in clinical trial design.
Berry, D A
2016-01-01
Designs of clinical trials have changed little since the advent of randomization in the 1940s. Modern innovations in designs are being driven by the increasing recognition in clinical research that diseases are heterogeneous and patients who apparently have the same disease require different therapies. This article describes some innovations in clinical trial design across therapeutic areas but with a focus on oncology. No one knows what the future holds for clinical trial design but the status quo of large trials that pretend the patient population is homogeneous is not sustainable, either economically or scientifically/medically. No one knows what the eventual business model and regulatory model will be, but they will be very different from today's. © 2015 American Society for Clinical Pharmacology and Therapeutics.
Mitochondrial dysfunction and sarcopenia of aging: from signaling pathways to clinical trials
Marzetti, Emanuele; Calvani, Riccardo; Cesari, Matteo; Buford, Thomas W.; Lorenzi, Maria; Behnke, Bradley J.; Leeuwenburgh, Christiaan
2013-01-01
Sarcopenia, the age-related loss of muscle mass and function, imposes a dramatic burden on individuals and society. The development of preventive and therapeutic strategies against sarcopenia is therefore perceived as an urgent need by health professionals and has instigated intensive research on the pathophysiology of this syndrome. The pathogenesis of sarcopenia is multifaceted and encompasses lifestyle habits, systemic factors (e.g., chronic inflammation and hormonal alterations), local environment perturbations (e.g., vascular dysfunction), and intramuscular specific processes. In this scenario, derangements in skeletal myocyte mitochondrial function are recognized as major factors contributing to the age-dependent muscle degeneration. In this review, we summarize prominent findings and controversial issues on the contribution of specific mitochondrial processes – including oxidative stress, quality control mechanisms and apoptotic signaling – on the development of sarcopenia. Extramuscular alterations accompanying the aging process with a potential impact on myocyte mitochondrial function are also discussed. We conclude with presenting methodological and safety considerations for the design of clinical trials targeting mitochondrial dysfunction to treat sarcopenia. Special emphasis is placed on the importance of monitoring the effects of an intervention on muscle mitochondrial function and identifying the optimal target population for the trial. PMID:23845738
Assaré, Rufin K.; Hürlimann, Eveline; Ouattara, Mamadou; N'Guessan, Nicaise A.; Tian-Bi, Yves-Nathan T.; Yapi, Ahoua; Yao, Patrick K.; Coulibaly, Jean T.; Knopp, Stefanie; N'Goran, Eliézer K.; Utzinger, Jürg
2016-01-01
We report baseline findings before the implementation of a 4-year intervention trial designed to assess the impact of three different school-based treatment schedules with praziquantel to sustain the control of intestinal schistosomiasis. The baseline survey was conducted in 75 schools of western Côte d'Ivoire previously identified with moderate Schistosoma mansoni endemicity (prevalence: 10–24% in children aged 13–14 years). Three stool samples collected over consecutive days were subjected to duplicate Kato-Katz thick smears each. A questionnaire was administered to collect village-specific information that is relevant for schistosomiasis transmission. Overall, 4,953 first graders (aged 5–8 years) and 7,011 school children (aged 9–12 years) had complete parasitologic data. The overall prevalence of S. mansoni was 5.4% among first graders and 22.1% in 9- to 12-year-old children. Open defecation was practiced in all villages. The current baseline findings will be important to better understand the dynamics of S. mansoni prevalence and intensity over the course of this trial that might be governed by village characteristics and specific treatment interventions. PMID:26598571
Yusen, Roger D; Criner, Gerard J; Sternberg, Alice L; Au, David H; Fuhlbrigge, Anne L; Albert, Richard K; Casaburi, Richard; Stoller, James K; Harrington, Kathleen F; Cooper, J Allen D; Diaz, Philip; Gay, Steven; Kanner, Richard; MacIntyre, Neil; Martinez, Fernando J; Piantadosi, Steven; Sciurba, Frank; Shade, David; Stibolt, Thomas; Tonascia, James; Wise, Robert; Bailey, William C
2018-01-01
The Long-Term Oxygen Treatment Trial demonstrated that long-term supplemental oxygen did not reduce time to hospital admission or death for patients who have stable chronic obstructive pulmonary disease and resting and/or exercise-induced moderate oxyhemoglobin desaturation, nor did it provide benefit for any other outcome measured in the trial. Nine months after initiation of patient screening, after randomization of 34 patients to treatment, a trial design amendment broadened the eligible population, expanded the primary outcome, and reduced the goal sample size. Within a few years, the protocol underwent minor modifications, and a second trial design amendment lowered the required sample size because of lower than expected treatment group crossover rates. After 5.5 years of recruitment, the trial met its amended sample size goal, and 1 year later, it achieved its follow-up goal. The process of publishing the trial results brought renewed scrutiny of the study design and the amendments. This article expands on the previously published design and methods information, provides the rationale for the amendments, and gives insight into the investigators' decisions about trial conduct. The story of the Long-Term Oxygen Treatment Trial may assist investigators in future trials, especially those that seek to assess the efficacy and safety of long-term oxygen therapy. Clinical trial registered with clinicaltrials.gov (NCT00692198).
Planning multi-arm screening studies within the context of a drug development program
Wason, James M S; Jaki, Thomas; Stallard, Nigel
2013-01-01
Screening trials are small trials used to decide whether an intervention is sufficiently promising to warrant a large confirmatory trial. Previous literature examined the situation where treatments are tested sequentially until one is considered sufficiently promising to take forward to a confirmatory trial. An important consideration for sponsors of clinical trials is how screening trials should be planned to maximize the efficiency of the drug development process. It has been found previously that small screening trials are generally the most efficient. In this paper we consider the design of screening trials in which multiple new treatments are tested simultaneously. We derive analytic formulae for the expected number of patients until a successful treatment is found, and propose methodology to search for the optimal number of treatments, and optimal sample size per treatment. We compare designs in which only the best treatment proceeds to a confirmatory trial and designs in which multiple treatments may proceed to a multi-arm confirmatory trial. We find that inclusion of a large number of treatments in the screening trial is optimal when only one treatment can proceed, and a smaller number of treatments is optimal when more than one can proceed. The designs we investigate are compared on a real-life set of screening designs. Copyright © 2013 John Wiley & Sons, Ltd. PMID:23529936
Harms, benefits, and the nature of interventions in pragmatic clinical trials.
Ali, Joseph; Andrews, Joseph E; Somkin, Carol P; Rabinovich, C Egla
2015-10-01
To produce evidence capable of informing healthcare decision making at all critical levels, pragmatic clinical trials are diverse both in terms of the type of intervention (medical, behavioral, and/or technological) and the target of intervention (patients, clinicians, and/or healthcare system processes). Patients and clinicians may be called on to participate as designers, investigators, intermediaries, or subjects of pragmatic clinical trials. Other members of the healthcare team, as well as the healthcare system itself, also may be affected directly or indirectly before, during, or after study implementation. This diversity in the types and targets of pragmatic clinical trial interventions has brought into focus the need to consider whether existing ethics and regulatory principles, policies, and procedures are appropriate for pragmatic clinical trials. Specifically, further examination is needed to identify how the types and targets of pragmatic clinical trial interventions may influence the assessment of net potential risk, understood as the balance of potential harms and benefits. In this article, we build on scholarship seeking to align ethics and regulatory requirements with potential research risks and propose an approach to the assessment of net risks that is sensitive to the diverse nature of pragmatic clinical trial interventions. We clarify the potential harms, burdens, benefits, and advantages of common types of pragmatic clinical trial interventions and discuss implications for patients, clinicians, and healthcare systems. © The Author(s) 2015.
Gros, Daniel F
2015-07-01
To address the limitations of disorder-specific approaches, newer transdiagnostic approaches to psychotherapy have been developed to provide a single treatment that is capable of addressing several, related disorders. However, the recruitment of multiple diagnoses presents many challenges to the traditional design of psychotherapy randomized controlled trials (RCTs). The goal of the manuscript is to present the challenges and rationale for designing a RCT for transdiagnostic treatment to inform and aid in the development of future investigations. A recently funded and ongoing RCT for Transdiagnostic Behavior Therapy (TBT) is used as an example to discuss the related design challenges. The TBT study involves the recruitment of 96 veteran participants with any of the following eight principal diagnoses: posttraumatic stress disorder, panic disorder, social anxiety disorder, obsessive compulsive disorder, generalized anxiety disorder, specific phobia, major depressive disorder, or persistent depressive disorder. Within the TBT study, participants will complete a semi-structured diagnostic interview and a series of transdiagnostic self-report measures to determine eligibility and assess baseline symptomatology. Qualifying participants will be randomized to TBT or control psychotherapy. Additional assessments will be completed at post-treatment and 6-month follow-up. Due to the transdiagnostic nature of the sample, adjustments to the recruitment and randomization procedures, selection of measures, selection of control psychotherapy, and analysis plan were required. These adjustments have implications to future trials on transdiagnostic psychotherapy protocols as well as future research in line with the transdiagnostic focus of the National Institute of Mental Health's Research Domain Criteria (RDoC) funding strategy. Published by Elsevier Inc.
Goldfeld, Sharon; Snow, Pamela; Eadie, Patricia; Munro, John; Gold, Lisa; Le, Ha N D; Orsini, Francesca; Shingles, Beth; Lee, Katherine; Connell, Judy; Watts, Amy
2017-01-01
Introduction Oral language and literacy competence are major influences on children’s developmental pathways and life success. Children who do not develop the necessary language and literacy skills in the early years of school then go on to face long-term difficulties. Improving teacher effectiveness may be a critical step in lifting oral language and literacy outcomes. The Classroom Promotion of Oral Language trial aims to determine whether a specifically designed teacher professional learning programme focusing on promoting oral language can lead to improved teacher knowledge and practice, and advance outcomes in oral language and literacy for early years school children, compared with usual practice. Methods and analysis This is a two-arm cluster multisite randomised controlled trial conducted within Catholic and Government primary schools across Victoria, Australia. The intervention comprises 4 days of face-to-face professional learning for teachers and ongoing implementation support via a specific worker. The primary outcome is reading ability of the students at grade 3, and the secondary outcomes are teacher knowledge and practice, student mental health, reading comprehension and language ability at grade 1; and literacy, writing and numeracy at grade 3. Economic evaluation will compare the incremental costs of the intervention to the measured primary and secondary outcomes. Ethics and dissemination This trial was approved by the Monash University Human Research Ethics Committee #CF13/2634-2013001403 and later transferred to the University of Melbourne #1545540. The investigators (including Government and Catholic partners) will communicate trial results to stakeholders, collaborators and participating schools and teachers via appropriate presentations and publications. Trial registration number ISRCTN77681972; Pre-results. PMID:29162571
Dispositional Optimism and Therapeutic Expectations in Early Phase Oncology Trials
Jansen, Lynn A.; Mahadevan, Daruka; Appelbaum, Paul S.; Klein, William MP; Weinstein, Neil D.; Mori, Motomi; Daffé, Racky; Sulmasy, Daniel P.
2016-01-01
Purpose Prior research has identified unrealistic optimism as a bias that might impair informed consent among patient-subjects in early phase oncology trials. Optimism, however, is not a unitary construct – it can also be defined as a general disposition, or what is called dispositional optimism. We assessed whether dispositional optimism would be related to high expectations for personal therapeutic benefit reported by patient-subjects in these trials but not to the therapeutic misconception. We also assessed how dispositional optimism related to unrealistic optimism. Methods Patient-subjects completed questionnaires designed to measure expectations for therapeutic benefit, dispositional optimism, unrealistic optimism, and the therapeutic misconception. Results Dispositional optimism was significantly associated with higher expectations for personal therapeutic benefit (Spearman r=0.333, p<0.0001), but was not associated with the therapeutic misconception. (Spearman r=−0.075, p=0.329). Dispositional optimism was weakly associated with unrealistic optimism (Spearman r=0.215, p=0.005). In multivariate analysis, both dispositional optimism (p=0.02) and unrealistic optimism (p<0.0001) were independently associated with high expectations for personal therapeutic benefit. Unrealistic optimism (p=.0001), but not dispositional optimism, was independently associated with the therapeutic misconception. Conclusion High expectations for therapeutic benefit among patient-subjects in early phase oncology trials should not be assumed to result from misunderstanding of specific information about the trials. Our data reveal that these expectations are associated with either a dispositionally positive outlook on life or biased expectations about specific aspects of trial participation. Not all manifestations of optimism are the same, and different types of optimism likely have different consequences for informed consent in early phase oncology research. PMID:26882017
Dispositional optimism and therapeutic expectations in early-phase oncology trials.
Jansen, Lynn A; Mahadevan, Daruka; Appelbaum, Paul S; Klein, William M P; Weinstein, Neil D; Mori, Motomi; Daffé, Racky; Sulmasy, Daniel P
2016-04-15
Prior research has identified unrealistic optimism as a bias that might impair informed consent among patient-subjects in early-phase oncology trials. However, optimism is not a unitary construct; it also can be defined as a general disposition, or what is called dispositional optimism. The authors assessed whether dispositional optimism would be related to high expectations for personal therapeutic benefit reported by patient-subjects in these trials but not to the therapeutic misconception. The authors also assessed how dispositional optimism related to unrealistic optimism. Patient-subjects completed questionnaires designed to measure expectations for therapeutic benefit, dispositional optimism, unrealistic optimism, and the therapeutic misconception. Dispositional optimism was found to be significantly associated with higher expectations for personal therapeutic benefit (Spearman rank correlation coefficient [r], 0.333; P<.0001), but was not associated with the therapeutic misconception (Spearman r, -0.075; P = .329). Dispositional optimism was found to be weakly associated with unrealistic optimism (Spearman r, 0.215; P = .005). On multivariate analysis, both dispositional optimism (P = .02) and unrealistic optimism (P<.0001) were found to be independently associated with high expectations for personal therapeutic benefit. Unrealistic optimism (P = .0001), but not dispositional optimism, was found to be independently associated with the therapeutic misconception. High expectations for therapeutic benefit among patient-subjects in early-phase oncology trials should not be assumed to result from misunderstanding of specific information regarding the trials. The data from the current study indicate that these expectations are associated with either a dispositionally positive outlook on life or biased expectations concerning specific aspects of trial participation. Not all manifestations of optimism are the same, and different types of optimism likely have different consequences for informed consent in early-phase oncology research. © 2016 American Cancer Society.
Some practical problems in implementing randomization.
Downs, Matt; Tucker, Kathryn; Christ-Schmidt, Heidi; Wittes, Janet
2010-06-01
While often theoretically simple, implementing randomization to treatment in a masked, but confirmable, fashion can prove difficult in practice. At least three categories of problems occur in randomization: (1) bad judgment in the choice of method, (2) design and programming errors in implementing the method, and (3) human error during the conduct of the trial. This article focuses on these latter two types of errors, dealing operationally with what can go wrong after trial designers have selected the allocation method. We offer several case studies and corresponding recommendations for lessening the frequency of problems in allocating treatment or for mitigating the consequences of errors. Recommendations include: (1) reviewing the randomization schedule before starting a trial, (2) being especially cautious of systems that use on-demand random number generators, (3) drafting unambiguous randomization specifications, (4) performing thorough testing before entering a randomization system into production, (5) maintaining a dataset that captures the values investigators used to randomize participants, thereby allowing the process of treatment allocation to be reproduced and verified, (6) resisting the urge to correct errors that occur in individual treatment assignments, (7) preventing inadvertent unmasking to treatment assignments in kit allocations, and (8) checking a sample of study drug kits to allow detection of errors in drug packaging and labeling. Although we performed a literature search of documented randomization errors, the examples that we provide and the resultant recommendations are based largely on our own experience in industry-sponsored clinical trials. We do not know how representative our experience is or how common errors of the type we have seen occur. Our experience underscores the importance of verifying the integrity of the treatment allocation process before and during a trial. Clinical Trials 2010; 7: 235-245. http://ctj.sagepub.com.
Kyte, Derek G.; Draper, Heather; Ives, Jonathan; Liles, Clive; Gheorghe, Adrian; Calvert, Melanie
2013-01-01
Background Patient reported outcomes (PROs) are increasingly assessed in clinical trials, and guidelines are available to inform the design and reporting of such trials. However, researchers involved in PRO data collection report that specific guidance on ‘in-trial’ activity (recruitment, data collection and data inputting) and the management of ‘concerning’ PRO data (i.e., data which raises concern for the well-being of the trial participant) appears to be lacking. The purpose of this review was to determine the extent and nature of published guidelines addressing these areas. Methods and Findings Systematic review of 1,362 articles identified 18 eligible papers containing ‘in-trial’ guidelines. Two independent authors undertook a qualitative content analysis of the selected papers. Guidelines presented in each of the articles were coded according to an a priori defined coding frame, which demonstrated reliability (pooled Kappa 0.86–0.97), and validity (<2% residual category coding). The majority of guidelines present were concerned with ‘pre-trial’ activities (72%), for example, outcome measure selection and study design issues, or ‘post-trial’ activities (16%) such as data analysis, reporting and interpretation. ‘In-trial’ guidelines represented 9.2% of all guidance across the papers reviewed, with content primarily focused on compliance, quality control, proxy assessment and reporting of data collection. There were no guidelines surrounding the management of concerning PRO data. Conclusions The findings highlight there are minimal in-trial guidelines in publication regarding PRO data collection and management in clinical trials. No guidance appears to exist for researchers involved with the handling of concerning PRO data. Guidelines are needed, which support researchers to manage all PRO data appropriately and which facilitate unbiased data collection. PMID:23560103
Kuhns, Lisa M; Mimiaga, Matthew J; Reisner, Sari L; Biello, Katie; Garofalo, Robert
2017-09-16
Transgender women in the U.S. have an alarmingly high incidence rate of HIV infection; condomless anal and vaginal sex is the primary risk behavior driving transmission. Young transgender women are the subpopulation at the highest risk for HIV. Despite this, there are no published randomized controlled efficacy trials testing interventions to reduce sexual risk for HIV among this group. This paper describes the design of a group-based intervention trial to reduce sexual risk for HIV acquisition and transmission in young transgender women. This study, funded by the National Institutes of Health, is a randomized controlled trial of a culturally-specific, empowerment-based, and group-delivered six-session HIV prevention intervention, Project LifeSkills, among sexually active young transgender women, ages 16-29 years in Boston and Chicago. Participants are randomized (2:2:1) to either the LifeSkills intervention, standard of care only, or a diet and nutrition time- and attention-matched control. At enrollment, all participants receive standardized HIV pre- and post-test counseling and screening for HIV and urogenital gonorrhea and chlamydia infections. The primary outcome is difference in the rate of change in the number of self-reported condomless anal or vaginal sex acts during the prior 4-months, assessed at baseline, 4-, 8-, and 12-month follow-up visits. Behavioral interventions to reduce sexual risk for HIV acquisition and transmission are sorely needed for young transgender women. This study will provide evidence to determine feasibility and efficacy in one of the first rigorously designed trials for this population. ClinicalTrials.gov number, NCT01575938 , registered March 29, 2012.
Pinto, Daniel; Robertson, M Clare; Hansen, Paul; Abbott, J Haxby
2011-06-17
Clinical guidelines for the treatment of hip and knee osteoarthritis recommend non-pharmacological and non-surgical treatments. Exercise treatments are recommended as primary strategies, but specific exercise programme components have not been specified. Early evidence indicates that manual physiotherapy is effective for hip and knee osteoarthritis. The Management of Osteoarthritis (MOA) Trial was designed to evaluate the effectiveness and cost-effectiveness of physiotherapist-led, individualised exercise, manual physiotherapy and a combination of these two interventions in the treatment of adults with hip or knee osteoarthrits. This paper describes the methods that will be used to conduct the economic evaluation of these interventions within the MOA Trial. This comprehensive economic evaluation will assess the incremental cost-effectiveness of physiotherapy plus usual care versus usual care alone from a societal perspective. The authors will conduct a cost-consequences analysis using end-points such as Outcomes Measures in Rheumatology Clinical Trials-Osteoarthritis Research Society International responder criteria and quality-adjusted life years. The evaluation will have a time horizon of 1 year (and so discounting will not be necessary). All costs will be reported in 2009 New Zealand dollars. The authors will address uncertainty via bootstrapping to calculate CIs for the mean incremental cost-effectiveness ratios and by performing sensitivity analyses. Ethical approval was granted by the Lower South Regional Ethics Committee of the New Zealand Ministry of Health (ethics reference: LRS/07/11/044). All participants of the MOA Trial provided written informed consent for the capture of their healthcare costs. We will submit the results of the study for publication irrespective of outcome. Clinical trials registration number ACTRN12608000130369.
Funding source and the quality of reports of chronic wounds trials: 2004 to 2011
2014-01-01
Background Critical commentaries suggest that wound care randomised controlled trials (RCTs) are often poorly reported with many methodological flaws. Furthermore, interventions in chronic wounds, rather than being drugs, are often medical devices for which there are no requirements for RCTs to bring products to market. RCTs in wounds trials therefore potentially represent a form of marketing. This study presents a methodological overview of chronic wound trials published between 2004 and 2011 and investigates the influence of industry funding on methodological quality. Methods A systematic search for RCTs for the treatment of chronic wounds published in the English language between 2004 and 2011 (inclusive) in the Cochrane Wounds Group Specialised Register of Trials was carried out. Data were extracted on aspects of trial design, conduct and quality including sample size, duration of follow-up, specification of a primary outcome, use of surrogate outcomes, and risks of bias. In addition, the prevalence of industry funding was assessed and its influence on the above aspects of trial design, conduct and quality was assessed. Results A total of 167 RCTs met our inclusion criteria. We found chronic wound trials often have short durations of follow-up (median 12 weeks), small sample sizes (median 63), fail to define a primary outcome in 41% of cases, and those that do define a primary outcome, use surrogate measures of healing in 40% of cases. Only 40% of trials used appropriate methods of randomisation, 25% concealed allocation and 34% blinded outcome assessors. Of the included trials, 41% were wholly or partially funded by industry, 33% declared non-commercial funding and 26% did not report a funding source. Industry funding was not statistically significantly associated with any measure of methodological quality, though this analysis was probably underpowered. Conclusions This overview confirms concerns raised about the methodological quality of RCTs in wound care and illustrates that greater efforts must be made to follow international standards for conducting and reporting RCTs. There is currently minimal evidence of an influence of industry funding on methodological quality although analyses had limited power and funding source was not reported for a quarter of studies. PMID:24422753
Funding source and the quality of reports of chronic wounds trials: 2004 to 2011.
Hodgson, Robert; Allen, Richard; Broderick, Ellen; Bland, J Martin; Dumville, Jo C; Ashby, Rebecca; Bell-Syer, Sally; Foxlee, Ruth; Hall, Jill; Lamb, Karen; Madden, Mary; O'Meara, Susan; Stubbs, Nikki; Cullum, Nicky
2014-01-14
Critical commentaries suggest that wound care randomised controlled trials (RCTs) are often poorly reported with many methodological flaws. Furthermore, interventions in chronic wounds, rather than being drugs, are often medical devices for which there are no requirements for RCTs to bring products to market. RCTs in wounds trials therefore potentially represent a form of marketing. This study presents a methodological overview of chronic wound trials published between 2004 and 2011 and investigates the influence of industry funding on methodological quality. A systematic search for RCTs for the treatment of chronic wounds published in the English language between 2004 and 2011 (inclusive) in the Cochrane Wounds Group Specialised Register of Trials was carried out.Data were extracted on aspects of trial design, conduct and quality including sample size, duration of follow-up, specification of a primary outcome, use of surrogate outcomes, and risks of bias. In addition, the prevalence of industry funding was assessed and its influence on the above aspects of trial design, conduct and quality was assessed. A total of 167 RCTs met our inclusion criteria. We found chronic wound trials often have short durations of follow-up (median 12 weeks), small sample sizes (median 63), fail to define a primary outcome in 41% of cases, and those that do define a primary outcome, use surrogate measures of healing in 40% of cases. Only 40% of trials used appropriate methods of randomisation, 25% concealed allocation and 34% blinded outcome assessors. Of the included trials, 41% were wholly or partially funded by industry, 33% declared non-commercial funding and 26% did not report a funding source. Industry funding was not statistically significantly associated with any measure of methodological quality, though this analysis was probably underpowered. This overview confirms concerns raised about the methodological quality of RCTs in wound care and illustrates that greater efforts must be made to follow international standards for conducting and reporting RCTs. There is currently minimal evidence of an influence of industry funding on methodological quality although analyses had limited power and funding source was not reported for a quarter of studies.
Jones, Ashley P; Conroy, Elizabeth; Williamson, Paula R; Clarke, Mike; Gamble, Carrol
2013-03-25
A systematic review, with or without a meta-analysis, should be undertaken to determine if the research question of interest has already been answered before a new trial begins. There has been limited research on how systematic reviews are used within the design of new trials, the aims of this study were to investigate how systematic reviews of earlier trials are used in the planning and design of new randomised trials. Documentation from the application process for all randomised trials funded by the National Institute for Health Research Health Technology Assessment (NIHR HTA) between 2006 and 2008 were obtained. This included the: commissioning brief (if appropriate), outline application, minutes of the Board meeting in which the outline application was discussed, full application, detailed project description, referee comments, investigator response to referee comments, Board minutes on the full application and the trial protocol. Data were extracted on references to systematic reviews and how any such reviews had been used in the planning and design of the trial. 50 randomised trials were funded by NIHR HTA during this period and documentation was available for 48 of these. The cohort was predominately individually randomised parallel trials aiming to detect superiority between two treatments for a single primary outcome. 37 trials (77.1%) referenced a systematic review within the application and 20 of these (i.e. 41.7% of the total) used information contained in the systematic review in the design or planning of the new trial. The main areas in which systematic reviews were used were in the selection or definition of an outcome to be measured in the trial (7 of 37, 18.9%), the sample size calculation (7, 18.9%), the duration of follow up (8, 21.6%) and the approach to describing adverse events (9, 24.3%). Boards did not comment on the presence/absence or use of systematic reviews in any application. Systematic reviews were referenced in most funded applications but just over half of these used the review to inform the design. There is an expectation from funders that applicants will use a systematic review to justify the need for a new trial but no expectation regarding further use of a systematic review to aid planning and design of the trial. Guidelines for applicants and funders should be developed to promote the use of systematic reviews in the design and planning of randomised trials, to optimise delivery of new studies informed by the most up-to-date evidence base and to minimise waste in research.
Recipient design in human communication: simple heuristics or perspective taking?
Blokpoel, Mark; van Kesteren, Marlieke; Stolk, Arjen; Haselager, Pim; Toni, Ivan; van Rooij, Iris
2012-01-01
Humans have a remarkable capacity for tuning their communicative behaviors to different addressees, a phenomenon also known as recipient design. It remains unclear how this tuning of communicative behavior is implemented during live human interactions. Classical theories of communication postulate that recipient design involves perspective taking, i.e., the communicator selects her behavior based on her hypotheses about beliefs and knowledge of the recipient. More recently, researchers have argued that perspective taking is computationally too costly to be a plausible mechanism in everyday human communication. These researchers propose that computationally simple mechanisms, or heuristics, are exploited to perform recipient design. Such heuristics may be able to adapt communicative behavior to an addressee with no consideration for the addressee's beliefs and knowledge. To test whether the simpler of the two mechanisms is sufficient for explaining the "how" of recipient design we studied communicators' behaviors in the context of a non-verbal communicative task (the Tacit Communication Game, TCG). We found that the specificity of the observed trial-by-trial adjustments made by communicators is parsimoniously explained by perspective taking, but not by simple heuristics. This finding is important as it suggests that humans do have a computationally efficient way of taking beliefs and knowledge of a recipient into account.
Blödt, Susanne; Schützler, Lena; Huang, Wenjing; Pach, Daniel; Brinkhaus, Benno; Hummelsberger, Josef; Kirschbaum, Barbara; Kuhlmann, Kirsten; Lao, Lixing; Liang, Fanrong; Mietzner, Anna; Mittring, Nadine; Müller, Sabine; Paul, Anna; Pimpao-Niederle, Carolina; Roll, Stephanie; Wu, Huangan; Zhu, Jiang; Witt, Claudia M
2013-04-11
Self-care acupressure might be successful in treating menstrual pain, which is common among young women. There is a need for comparative effectiveness research with stakeholder engagement in all phases seeking to address the needs of decision-makers. Our aim was to design a study on the effectiveness of additional self-care acupressure for menstrual pain comparing usual care alone using different methods of stakeholder engagement. The study was designed using multiple mixed methods for stakeholder engagement. Based on the results of a survey and focus group discussion, a stakeholder advisory group developed the study design. Stakeholder engagement resulted in a two-arm pragmatic randomized trial. Two hundred and twenty women aged 18 to 25 years with menstrual pain will be included in the study. Outcome measurement will be done using electronic questionnaires provided by a study specific mobile application (App). Primary outcome will be the mean pain intensity at the days of pain during the third menstruation after therapy start. Stakeholder engagement helped to develop a study design that better serves the needs of decision makers, including an App as a modern tool for both intervention and data collection in a young target group. Clinicaltrials.gov identifier http://NCT01582724.
Recipient design in human communication: simple heuristics or perspective taking?
Blokpoel, Mark; van Kesteren, Marlieke; Stolk, Arjen; Haselager, Pim; Toni, Ivan; van Rooij, Iris
2012-01-01
Humans have a remarkable capacity for tuning their communicative behaviors to different addressees, a phenomenon also known as recipient design. It remains unclear how this tuning of communicative behavior is implemented during live human interactions. Classical theories of communication postulate that recipient design involves perspective taking, i.e., the communicator selects her behavior based on her hypotheses about beliefs and knowledge of the recipient. More recently, researchers have argued that perspective taking is computationally too costly to be a plausible mechanism in everyday human communication. These researchers propose that computationally simple mechanisms, or heuristics, are exploited to perform recipient design. Such heuristics may be able to adapt communicative behavior to an addressee with no consideration for the addressee's beliefs and knowledge. To test whether the simpler of the two mechanisms is sufficient for explaining the “how” of recipient design we studied communicators' behaviors in the context of a non-verbal communicative task (the Tacit Communication Game, TCG). We found that the specificity of the observed trial-by-trial adjustments made by communicators is parsimoniously explained by perspective taking, but not by simple heuristics. This finding is important as it suggests that humans do have a computationally efficient way of taking beliefs and knowledge of a recipient into account. PMID:23055960
Bayesian adaptive phase II screening design for combination trials
Cai, Chunyan; Yuan, Ying; Johnson, Valen E
2013-01-01
Background Trials of combination therapies for the treatment of cancer are playing an increasingly important role in the battle against this disease. To more efficiently handle the large number of combination therapies that must be tested, we propose a novel Bayesian phase II adaptive screening design to simultaneously select among possible treatment combinations involving multiple agents. Methods Our design is based on formulating the selection procedure as a Bayesian hypothesis testing problem in which the superiority of each treatment combination is equated to a single hypothesis. During the trial conduct, we use the current values of the posterior probabilities of all hypotheses to adaptively allocate patients to treatment combinations. Results Simulation studies show that the proposed design substantially outperforms the conventional multiarm balanced factorial trial design. The proposed design yields a significantly higher probability for selecting the best treatment while allocating substantially more patients to efficacious treatments. Limitations The proposed design is most appropriate for the trials combining multiple agents and screening out the efficacious combination to be further investigated. Conclusions The proposed Bayesian adaptive phase II screening design substantially outperformed the conventional complete factorial design. Our design allocates more patients to better treatments while providing higher power to identify the best treatment at the end of the trial. PMID:23359875
Critical review, with an optimistic outlook, on Boron Neutron Capture Therapy (BNCT).
Moss, Raymond L
2014-06-01
The first BNCT trials took place in the USA in the early 1960's, yet BNCT is still far from mainstream medicine. Nonetheless, in recent years, reported results in the treatment of head and neck cancer and recurrent glioma, coupled with the progress in developing linear accelerators specifically for BNCT applications, have given some optimism to the future of BNCT. This article provides a brief reminder on the ups and downs of the history of BNCT and supports the view that controlled and prospective clinical trials with a modern design will make BNCT an evidence-based treatment modality within the coming decade. © 2013 Elsevier Ltd. All rights reserved.
Vandelanotte, Corneel; Maher, Carol A
2015-01-01
Despite their popularity and potential to promote health in large populations, the effectiveness of online social networks (e.g., Facebook) to improve health behaviors has been somewhat disappointing. Most of the research examining the effectiveness of such interventions has used randomized controlled trials (RCTs). It is asserted that the modest outcomes may be due to characteristics specific to both online social networks and RCTs. The highly controlled nature of RCTs stifles the dynamic nature of online social networks. Alternative and ecologically valid research designs that evaluate online social networks in real-life conditions are needed to advance the science in this area.
Chang, Ken C N; Galuska, Stefan; Weiner, Russell; Marton, Matthew J
2013-01-01
Somatic mutations identified on genes related to the cancer-developing signaling pathways have drawn attention in the field of personalized medicine in recent years. Treatments developed to target a specific signaling pathway may not be effective when tumor activating mutations occur downstream of the target and bypass the targeted mechanism. For instance, mutations detected in KRAS/BRAF/NRAS genes can lead to EGFR-independent intracellular signaling pathway activation. Most patients with these mutations do not respond well to anti-EGFR treatment. In an effort to detect various mutations in FFPE tissue samples among multiple solid tumor types for patient stratification many mutation assays were evaluated. Since there were more than 30 specific mutations among three targeted RAS/RAF oncogenes that could activate MAPK pathway genes, a custom designed Single Nucleotide Primer Extension (SNPE) multiplexing mutation assay was developed and analytically validated as a clinical trial assay. Throughout the process of developing and validating the assay we overcame many technical challenges which include: the designing of PCR primers for FFPE tumor tissue samples versus normal blood samples, designing of probes for detecting consecutive nucleotide double mutations, the kinetics and thermodynamics aspects of probes competition among themselves and against target PCR templates, as well as validating an assay when positive control tumor tissue or cell lines with specific mutations are not available. We used Next Generation sequencing to resolve discordant calls between the SNPE mutation assay and Sanger sequencing. We also applied a triplicate rule to reduce potential false positives and false negatives, and proposed special considerations including pre-define a cut-off percentage for detecting very low mutant copies in the wild-type DNA background.
A Bayesian-frequentist two-stage single-arm phase II clinical trial design.
Dong, Gaohong; Shih, Weichung Joe; Moore, Dirk; Quan, Hui; Marcella, Stephen
2012-08-30
It is well-known that both frequentist and Bayesian clinical trial designs have their own advantages and disadvantages. To have better properties inherited from these two types of designs, we developed a Bayesian-frequentist two-stage single-arm phase II clinical trial design. This design allows both early acceptance and rejection of the null hypothesis ( H(0) ). The measures (for example probability of trial early termination, expected sample size, etc.) of the design properties under both frequentist and Bayesian settings are derived. Moreover, under the Bayesian setting, the upper and lower boundaries are determined with predictive probability of trial success outcome. Given a beta prior and a sample size for stage I, based on the marginal distribution of the responses at stage I, we derived Bayesian Type I and Type II error rates. By controlling both frequentist and Bayesian error rates, the Bayesian-frequentist two-stage design has special features compared with other two-stage designs. Copyright © 2012 John Wiley & Sons, Ltd.
Chang, Rowland W; Semanik, Pamela A; Lee, Jungwha; Feinglass, Joseph; Ehrlich-Jones, Linda; Dunlop, Dorothy D
2014-11-01
Over 21 million Americans report an arthritis-attributable activity limitation. Knee osteoarthritis (OA) and rheumatoid arthritis (RA) are two of the most common/disabling forms of arthritis. Various forms of physical activity (PA) can improve a variety of health outcomes and reduce health care costs, but the proportion of the US population engaging in the recommended amount of PA is low and even lower among those with arthritis. The Improving Motivation for Physical Activity in Arthritis Clinical Trial (IMPAACT) is a randomized clinical trial that studied the effects of a lifestyle PA promotion intervention on pain and physical function outcomes. The IMPAACT intervention was based on a chronic care/disease management model in which allied health professionals promote patient self-management activities outside of traditional physician office encounters. The program was a motivational interviewing-based, individualized counseling and referral intervention, directed by a comprehensive assessment of individual patient barriers and strengths related to PA performance. The specific aims of IMPAACT were to test the efficacy of the IMPAACT intervention for persons with arthritis (N=185 persons with RA and 155 persons with knee OA) in improving arthritis-specific and generic self-reported pain and Physical Function outcomes, observed measures of function, and objectively measured and self-reported PA levels. Details of the stratified-randomized study design, subject recruitment, and data collection are described. The results from IMPAACT will generate empiric evidence pertaining to increasing PA levels in persons with arthritis and result in widely applicable strategies for health behavior change. Copyright © 2014 Elsevier Inc. All rights reserved.
Huckans, Marilyn; Hutson, Lee; Twamley, Elizabeth; Jak, Amy; Kaye, Jeffrey; Storzbach, Daniel
2013-01-01
Objective To evaluate the efficacy of cognitive rehabilitation therapies (CRTs) for mild cognitive impairment (MCI). Our review revealed a need for evidence-based treatments for MCI and a lack of a theoretical rehabilitation model to guide the development and evaluation of these interventions. We have thus proposed a theoretical rehabilitation model of MCI that yields key intervention targets - cognitive compromise, functional compromise, neuropsychiatric symptoms, and modifiable risk and protective factors known to be associated with MCI and dementia. Our model additionally defines specific cognitive rehabilitation approaches that may directly or indirectly target key outcomes - restorative cognitive training, compensatory cognitive training, lifestyle interventions, and psychotherapeutic techniques. Methods Fourteen randomized controlled trials met inclusion criteria and were reviewed. Results Studies markedly varied in terms of intervention approaches and selected outcome measures and were frequently hampered by design limitations. The bulk of the evidence suggested that CRTs can change targeted behaviors in individuals with MCI and that CRTs are associated with improvements in objective cognitive performance, but the pattern of effects on specific cognitive domains was inconsistent across studies. Other important outcomes (i.e., daily functioning, quality of life, neuropsychiatric symptom severity) were infrequently assessed across studies. Few studies evaluated long-term outcomes or the impact of CRTs on conversion rates from MCI to dementia or normal cognition. Conclusions Overall, results from trials are promising but inconclusive. Additional well-designed and adequately powered trials are warranted and required before CRTs for MCI can be considered evidence based. PMID:23471631
Cho, Hallie S; Tao, Gregory D; Winter, Amos
2012-01-01
In developing world health clinics, incidence of surgical site infection is 2 to 10 times higher than in developed world hospitals. This paper identifies lack of availability of appropriately designed, low-cost autoclaves in developing world health clinics as a major contributing factor to the dramatic gap in surgical site infection rates. The paper describes the process of developing a low-cost autoclave that addresses the unique challenges faced by developing world primary health clinics and discusses how appropriateness of design was determined. The resulting pressure cooker-based autoclave design was fabricated and tested against the CDC specifications. Twelve partnering clinics in Nepal trialed these autoclaves from July until December 2012.
Series: Pragmatic trials and real world evidence: Paper 1. Introduction.
Zuidgeest, Mira G P; Goetz, Iris; Groenwold, Rolf H H; Irving, Elaine; van Thiel, Ghislaine J M W; Grobbee, Diederick E
2017-08-01
This is the introductory paper in a series of eight papers. In this series, we integrate the theoretical design options with the practice of conducting pragmatic trials. For most new market-approved treatments, the clinical evidence is insufficient to fully guide physicians and policy makers in choosing the optimal treatment for their patients. Pragmatic trials can fill this gap, by providing evidence on the relative effectiveness of a treatment strategy in routine clinical practice, already in an early phase of development, while maintaining the strength of randomized controlled trials. Selecting the setting, study population, mode of intervention, comparator, and outcome are crucial in designing pragmatic trials. In combination with monitoring and data collection that does not change routine care, this will enable appropriate generalization to the target patient group in clinical practice. To benefit from the full potential of pragmatic trials, there is a need for guidance and tools in designing these studies while ensuring operational feasibility. This paper introduces the concept of pragmatic trial design. The complex interplay between pragmatic design options, feasibility, stakeholder acceptability, validity, precision, and generalizability will be clarified. In this way, balanced design choices can be made in pragmatic trials with an optimal chance of success in practice. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.
Biomarkers and surrogate endpoints in clinical trials.
Fleming, Thomas R; Powers, John H
2012-11-10
One of the most important considerations in designing clinical trials is the choice of outcome measures. These outcome measures could be clinically meaningful endpoints that are direct measures of how patients feel, function, and survive. Alternatively, indirect measures, such as biomarkers that include physical signs of disease, laboratory measures, and radiological tests, often are considered as replacement endpoints or 'surrogates' for clinically meaningful endpoints. We discuss the definitions of clinically meaningful endpoints and surrogate endpoints, and provide examples from recent clinical trials. We provide insight into why indirect measures such as biomarkers may fail to provide reliable evidence about the benefit-to-risk profile of interventions. We also discuss the nature of evidence that is important in assessing whether treatment effects on a biomarker reliably predict effects on a clinically meaningful endpoint, and provide insights into why this reliability is specific to the context of use of the biomarker. Copyright © 2012 John Wiley & Sons, Ltd.
Biomarkers and Surrogate Endpoints In Clinical Trials
Fleming, Thomas R.; Powers, John H
2012-01-01
One of the most important considerations in designing clinical trials is the choice of outcome measures. These outcome measures could be clinically meaningful endpoints that are direct measures of how patients feel, function and survive. Alternatively, indirect measures, such as biomarkers that include physical signs of disease, laboratory measures and radiological tests, often are considered as replacement endpoints or “surrogates” for clinically meaningful endpoints. We discuss the definitions of clinically meaningful endpoints and surrogate endpoints, and provide examples from recent clinical trials. We provide insight into why indirect measures such as biomarkers may fail to provide reliable evidence about the benefit-to-risk profile of interventions. We also discuss the nature of evidence that is important in assessing whether treatment effects on a biomarker reliably predict effects on a clinically meaningful endpoint, and provide insights into why this reliability is specific to the context of use of the biomarker. . PMID:22711298
A High Precision $3.50 Open Source 3D Printed Rain Gauge Calibrator
NASA Astrophysics Data System (ADS)
Lopez Alcala, J. M.; Udell, C.; Selker, J. S.
2017-12-01
Currently available rain gauge calibrators tend to be designed for specific rain gauges, are expensive, employ low-precision water reservoirs, and do not offer the flexibility needed to test the ever more popular small-aperture rain gauges. The objective of this project was to develop and validate a freely downloadable, open-source, 3D printed rain gauge calibrator that can be adjusted for a wide range of gauges. The proposed calibrator provides for applying low, medium, and high intensity flow, and allows the user to modify the design to conform to unique system specifications based on parametric design, which may be modified and printed using CAD software. To overcome the fact that different 3D printers yield different print qualities, we devised a simple post-printing step that controlled critical dimensions to assure robust performance. Specifically, the three orifices of the calibrator are drilled to reach the three target flow rates. Laboratory tests showed that flow rates were consistent between prints, and between trials of each part, while the total applied water was precisely controlled by the use of a volumetric flask as the reservoir.
Boessen, Ruud; van der Baan, Frederieke; Groenwold, Rolf; Egberts, Antoine; Klungel, Olaf; Grobbee, Diederick; Knol, Mirjam; Roes, Kit
2013-01-01
Two-stage clinical trial designs may be efficient in pharmacogenetics research when there is some but inconclusive evidence of effect modification by a genomic marker. Two-stage designs allow to stop early for efficacy or futility and can offer the additional opportunity to enrich the study population to a specific patient subgroup after an interim analysis. This study compared sample size requirements for fixed parallel group, group sequential, and adaptive selection designs with equal overall power and control of the family-wise type I error rate. The designs were evaluated across scenarios that defined the effect sizes in the marker positive and marker negative subgroups and the prevalence of marker positive patients in the overall study population. Effect sizes were chosen to reflect realistic planning scenarios, where at least some effect is present in the marker negative subgroup. In addition, scenarios were considered in which the assumed 'true' subgroup effects (i.e., the postulated effects) differed from those hypothesized at the planning stage. As expected, both two-stage designs generally required fewer patients than a fixed parallel group design, and the advantage increased as the difference between subgroups increased. The adaptive selection design added little further reduction in sample size, as compared with the group sequential design, when the postulated effect sizes were equal to those hypothesized at the planning stage. However, when the postulated effects deviated strongly in favor of enrichment, the comparative advantage of the adaptive selection design increased, which precisely reflects the adaptive nature of the design. Copyright © 2013 John Wiley & Sons, Ltd.
Hargreaves, James R; Fearon, Elizabeth; Davey, Calum; Phillips, Andrew; Cambiano, Valentina; Cowan, Frances M
2016-01-05
Pragmatic cluster-randomised trials should seek to make unbiased estimates of effect and be reported according to CONSORT principles, and the study population should be representative of the target population. This is challenging when conducting trials amongst 'hidden' populations without a sample frame. We describe a pair-matched cluster-randomised trial of a combination HIV-prevention intervention to reduce the proportion of female sex workers (FSW) with a detectable HIV viral load in Zimbabwe, recruiting via respondent driven sampling (RDS). We will cross-sectionally survey approximately 200 FSW at baseline and at endline to characterise each of 14 sites. RDS is a variant of chain referral sampling and has been adapted to approximate random sampling. Primary analysis will use the 'RDS-2' method to estimate cluster summaries and will adapt Hayes and Moulton's '2-step' method to adjust effect estimates for individual-level confounders and further adjust for cluster baseline prevalence. We will adapt CONSORT to accommodate RDS. In the absence of observable refusal rates, we will compare the recruitment process between matched pairs. We will need to investigate whether cluster-specific recruitment or the intervention itself affects the accuracy of the RDS estimation process, potentially causing differential biases. To do this, we will calculate RDS-diagnostic statistics for each cluster at each time point and compare these statistics within matched pairs and time points. Sensitivity analyses will assess the impact of potential biases arising from assumptions made by the RDS-2 estimation. We are not aware of any other completed pragmatic cluster RCTs that are recruiting participants using RDS. Our statistical design and analysis approach seeks to transparently document participant recruitment and allow an assessment of the representativeness of the study to the target population, a key aspect of pragmatic trials. The challenges we have faced in the design of this trial are likely to be shared in other contexts aiming to serve the needs of legally and/or socially marginalised populations for which no sampling frame exists and especially when the social networks of participants are both the target of intervention and the means of recruitment. The trial was registered at Pan African Clinical Trials Registry (PACTR201312000722390) on 9 December 2013.
A Bayesian adaptive design for biomarker trials with linked treatments.
Wason, James M S; Abraham, Jean E; Baird, Richard D; Gournaris, Ioannis; Vallier, Anne-Laure; Brenton, James D; Earl, Helena M; Mander, Adrian P
2015-09-01
Response to treatments is highly heterogeneous in cancer. Increased availability of biomarkers and targeted treatments has led to the need for trial designs that efficiently test new treatments in biomarker-stratified patient subgroups. We propose a novel Bayesian adaptive randomisation (BAR) design for use in multi-arm phase II trials where biomarkers exist that are potentially predictive of a linked treatment's effect. The design is motivated in part by two phase II trials that are currently in development. The design starts by randomising patients to the control treatment or to experimental treatments that the biomarker profile suggests should be active. At interim analyses, data from treated patients are used to update the allocation probabilities. If the linked treatments are effective, the allocation remains high; if ineffective, the allocation changes over the course of the trial to unlinked treatments that are more effective. Our proposed design has high power to detect treatment effects if the pairings of treatment with biomarker are correct, but also performs well when alternative pairings are true. The design is consistently more powerful than parallel-groups stratified trials. This BAR design is a powerful approach to use when there are pairings of biomarkers with treatments available for testing simultaneously.
Yeh, Hsin-Chieh; Clark, Jeanne M; Emmons, Karen E; Moore, Reneé H; Bennett, Gary G; Warner, Erica T; Sarwer, David B; Jerome, Gerald J; Miller, Edgar R; Volger, Sheri; Louis, Thomas A; Wells, Barbara; Wadden, Thomas A; Colditz, Graham A; Appel, Lawrence J
2010-08-01
The National Heart, Lung, and Blood Institute (NHLBI) funded three institutions to conduct effectiveness trials of weight loss interventions in primary care settings. Unlike traditional multi-center clinical trials, each study was established as an independent trial with a distinct protocol. Still, efforts were made to coordinate and standardize several aspects of the trials. The three trials formed a collaborative group, the 'Practice-based Opportunities for Weight Reduction (POWER) Trials Collaborative Research Group.' We describe the common and distinct features of the three trials, the key characteristics of the collaborative group, and the lessons learned from this novel organizational approach. The Collaborative Research Group consists of three individual studies: 'Be Fit, Be Well' (Washington University in St. Louis/Harvard University), 'POWER Hopkins' (Johns Hopkins), and 'POWER-UP' (University of Pennsylvania). There are a total of 15 participating clinics with ~1100 participants. The common primary outcome is change in weight at 24 months of follow-up, but each protocol has trial-specific elements including different interventions and different secondary outcomes. A Resource Coordinating Unit at Johns Hopkins provides administrative support. The Collaborative Research Group established common components to facilitate potential cross-site comparisons. The main advantage of this approach is to develop and evaluate several interventions, when there is insufficient evidence to test one or two approaches, as would be done in a traditional multi-center trial. The challenges of the organizational design include the complex decision-making process, the extent of potential data pooling, time intensive efforts to standardize reports, and the additional responsibilities of the DSMB to monitor three distinct protocols.
Hierarchical acquisition of visual specificity in spatial contextual cueing.
Lie, Kin-Pou
2015-01-01
Spatial contextual cueing refers to visual search performance's being improved when invariant associations between target locations and distractor spatial configurations are learned incidentally. Using the instance theory of automatization and the reverse hierarchy theory of visual perceptual learning, this study explores the acquisition of visual specificity in spatial contextual cueing. Two experiments in which detailed visual features were irrelevant for distinguishing between spatial contexts found that spatial contextual cueing was visually generic in difficult trials when the trials were not preceded by easy trials (Experiment 1) but that spatial contextual cueing progressed to visual specificity when difficult trials were preceded by easy trials (Experiment 2). These findings support reverse hierarchy theory, which predicts that even when detailed visual features are irrelevant for distinguishing between spatial contexts, spatial contextual cueing can progress to visual specificity if the stimuli remain constant, the task is difficult, and difficult trials are preceded by easy trials. However, these findings are inconsistent with instance theory, which predicts that when detailed visual features are irrelevant for distinguishing between spatial contexts, spatial contextual cueing will not progress to visual specificity. This study concludes that the acquisition of visual specificity in spatial contextual cueing is more plausibly hierarchical, rather than instance-based.
75 FR 73104 - Clinical Development Programs for Sedation Products; Request for Assistance
Federal Register 2010, 2011, 2012, 2013, 2014
2010-11-29
... sedation claims? Would dose-escalation comparative trial designs be useful in studying sedation products? 5... understanding the physiology of sedation and clinical trial design issues related to the development of sedation... to procedural and intensive care unit (ICU) sedation, as well as associated clinical trial design...
Methodological considerations in the design and implementation of clinical trials.
Cirrincione, Constance T; Lavoie Smith, Ellen M; Pang, Herbert
2014-02-01
To review study design issues related to clinical trials led by oncology nurses, with special attention to those conducted within the cooperative group setting; to emphasize the importance of the statistician's role in the process of clinical trials. Studies available at clinicaltrials.gov using experimental designs that have been published in peer-reviewed journals; cooperative group trials are highlighted. The clinical trial is a primary means to test intervention efficacy. A properly designed and powered study with clear and measurable objectives is as important as the intervention itself. Collaboration among the study team, including the statistician, is central in developing and conducting appropriately designed studies. For optimal results, collaboration is an ongoing process that should begin early on. Copyright © 2014 Elsevier Inc. All rights reserved.
Chase, J Geoffrey; Preiser, Jean-Charles; Dickson, Jennifer L; Pironet, Antoine; Chiew, Yeong Shiong; Pretty, Christopher G; Shaw, Geoffrey M; Benyo, Balazs; Moeller, Knut; Safaei, Soroush; Tawhai, Merryn; Hunter, Peter; Desaive, Thomas
2018-02-20
Critical care, like many healthcare areas, is under a dual assault from significantly increasing demographic and economic pressures. Intensive care unit (ICU) patients are highly variable in response to treatment, and increasingly aging populations mean ICUs are under increasing demand and their cohorts are increasingly ill. Equally, patient expectations are growing, while the economic ability to deliver care to all is declining. Better, more productive care is thus the big challenge. One means to that end is personalised care designed to manage the significant inter- and intra-patient variability that makes the ICU patient difficult. Thus, moving from current "one size fits all" protocolised care to adaptive, model-based "one method fits all" personalised care could deliver the required step change in the quality, and simultaneously the productivity and cost, of care. Computer models of human physiology are a unique tool to personalise care, as they can couple clinical data with mathematical methods to create subject-specific models and virtual patients to design new, personalised and more optimal protocols, as well as to guide care in real-time. They rely on identifying time varying patient-specific parameters in the model that capture inter- and intra-patient variability, the difference between patients and the evolution of patient condition. Properly validated, virtual patients represent the real patients, and can be used in silico to test different protocols or interventions, or in real-time to guide care. Hence, the underlying models and methods create the foundation for next generation care, as well as a tool for safely and rapidly developing personalised treatment protocols over large virtual cohorts using virtual trials. This review examines the models and methods used to create virtual patients. Specifically, it presents the models types and structures used and the data required. It then covers how to validate the resulting virtual patients and trials, and how these virtual trials can help design and optimise clinical trial. Links between these models and higher order, more complex physiome models are also discussed. In each section, it explores the progress reported up to date, especially on core ICU therapies in glycemic, circulatory and mechanical ventilation management, where high cost and frequency of occurrence provide a significant opportunity for model-based methods to have measurable clinical and economic impact. The outcomes are readily generalised to other areas of medical care.
Medical Management of Oral Lichen Planus: A Systematic Review
Chokshi, Krunal; Desai, Sachin; Malu, Rahul; Chokshi, Achala
2016-01-01
Introduction Oral Lichen Planus (OLP) is a chronic inflammatory, T-cell-mediated autoimmune oral mucosal disease with unclear aetiology. The clinical management of OLP poses considerable difficulties to the oral physician. Aim The aim was to assess the efficacy of any form of intervention used to medically manage OLP. Materials and Methods We searched and analysed the following databases (from January 1990 to December 2014):- Cochrane Oral Health Group Trials Register, Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE and EMBASE. All Randomised Controlled Trials (RCTs) for the medical management of OLP which compared active treatment with placebo or between active treatments were considered in this systematic review. Participants of any age, gender or race having symptomatic OLP (including mixed forms), unconnected to any identifiable cause (e.g. lichenoid drug reactions) and confirmed by histopathology have been included. Interventions of all types, including topical treatments or systemic drugs of variable dosage, duration & frequency of delivery have been considered. All the trials identified were appraised by five review authors and the data for all the trials were synthesised using specifically designed data extraction form. Binary data has been presented as risk ratios (RR) with 95% confidence intervals (CI) and continuous data as mean differences (MD) with 95% CIs. Results A total of 35 RCTs were included in this systematic review on medical management of OLP. No strong evidence suggesting superiority of any specific intervention in reducing pain and clinical signs of OLP were shown by the RCTs included here. Conclusion Future RCTs on a larger scale, adopting standardized outcome assessing parameters should be considered. PMID:27042598