Download or read book The Use of Restricted Significance Tests in Clinical Trials written by David S. Salsburg and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 183 pages. Available in PDF, EPUB and Kindle. Book excerpt: The reader will soon find that this is more than a "how-to-do-it" book. It describes a philosophical approach to the use of statistics in the analysis of clinical trials. I have come gradually to the position described here, but I have not come that way alone. This approach is heavily influenced by my reading the papers of R.A. Fisher, F.S. Anscombe, F. Mosteller, and J. Neyman. But the most important influences have been those of my medical colleagues, who had important real-life medical questions that needed to be answered. Statistical methods depend on abstract mathematical theorems and often complicated algorithms on the computer. But these are only a means to an end, because in the end the statistical techniques we apply to clinical studies have to provide useful answers. When I was studying martingales and symbolic logic in graduate school, my wife, Fran, had to be left out of the intellectual excitement. But, as she looked on, she kept asking me how is this knowledge useful. That question, what can you do with this? haunted my studies. When I began working in bio statistics, she continued asking me where it was all going, and I had to explain what I was doing in terms of the practical problems that were being ad dressed.

Download or read book The Use of Restricted Significance Tests in Clinical Trials written by David Salsburg and published by . This book was released on 1992-01-01 with total page 173 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Small Clinical Trials written by Institute of Medicine and published by National Academies Press. This book was released on 2001-01-01 with total page 221 pages. Available in PDF, EPUB and Kindle. Book excerpt: Clinical trials are used to elucidate the most appropriate preventive, diagnostic, or treatment options for individuals with a given medical condition. Perhaps the most essential feature of a clinical trial is that it aims to use results based on a limited sample of research participants to see if the intervention is safe and effective or if it is comparable to a comparison treatment. Sample size is a crucial component of any clinical trial. A trial with a small number of research participants is more prone to variability and carries a considerable risk of failing to demonstrate the effectiveness of a given intervention when one really is present. This may occur in phase I (safety and pharmacologic profiles), II (pilot efficacy evaluation), and III (extensive assessment of safety and efficacy) trials. Although phase I and II studies may have smaller sample sizes, they usually have adequate statistical power, which is the committee's definition of a "large" trial. Sometimes a trial with eight participants may have adequate statistical power, statistical power being the probability of rejecting the null hypothesis when the hypothesis is false. Small Clinical Trials assesses the current methodologies and the appropriate situations for the conduct of clinical trials with small sample sizes. This report assesses the published literature on various strategies such as (1) meta-analysis to combine disparate information from several studies including Bayesian techniques as in the confidence profile method and (2) other alternatives such as assessing therapeutic results in a single treated population (e.g., astronauts) by sequentially measuring whether the intervention is falling above or below a preestablished probability outcome range and meeting predesigned specifications as opposed to incremental improvement.

Download or read book The Prevention and Treatment of Missing Data in Clinical Trials written by National Research Council and published by National Academies Press. This book was released on 2010-12-21 with total page 163 pages. Available in PDF, EPUB and Kindle. Book excerpt: Randomized clinical trials are the primary tool for evaluating new medical interventions. Randomization provides for a fair comparison between treatment and control groups, balancing out, on average, distributions of known and unknown factors among the participants. Unfortunately, these studies often lack a substantial percentage of data. This missing data reduces the benefit provided by the randomization and introduces potential biases in the comparison of the treatment groups. Missing data can arise for a variety of reasons, including the inability or unwillingness of participants to meet appointments for evaluation. And in some studies, some or all of data collection ceases when participants discontinue study treatment. Existing guidelines for the design and conduct of clinical trials, and the analysis of the resulting data, provide only limited advice on how to handle missing data. Thus, approaches to the analysis of data with an appreciable amount of missing values tend to be ad hoc and variable. The Prevention and Treatment of Missing Data in Clinical Trials concludes that a more principled approach to design and analysis in the presence of missing data is both needed and possible. Such an approach needs to focus on two critical elements: (1) careful design and conduct to limit the amount and impact of missing data and (2) analysis that makes full use of information on all randomized participants and is based on careful attention to the assumptions about the nature of the missing data underlying estimates of treatment effects. In addition to the highest priority recommendations, the book offers more detailed recommendations on the conduct of clinical trials and techniques for analysis of trial data.

Download or read book Sharing Clinical Trial Data written by Institute of Medicine and published by National Academies Press. This book was released on 2015-04-20 with total page 304 pages. Available in PDF, EPUB and Kindle. Book excerpt: Data sharing can accelerate new discoveries by avoiding duplicative trials, stimulating new ideas for research, and enabling the maximal scientific knowledge and benefits to be gained from the efforts of clinical trial participants and investigators. At the same time, sharing clinical trial data presents risks, burdens, and challenges. These include the need to protect the privacy and honor the consent of clinical trial participants; safeguard the legitimate economic interests of sponsors; and guard against invalid secondary analyses, which could undermine trust in clinical trials or otherwise harm public health. Sharing Clinical Trial Data presents activities and strategies for the responsible sharing of clinical trial data. With the goal of increasing scientific knowledge to lead to better therapies for patients, this book identifies guiding principles and makes recommendations to maximize the benefits and minimize risks. This report offers guidance on the types of clinical trial data available at different points in the process, the points in the process at which each type of data should be shared, methods for sharing data, what groups should have access to data, and future knowledge and infrastructure needs. Responsible sharing of clinical trial data will allow other investigators to replicate published findings and carry out additional analyses, strengthen the evidence base for regulatory and clinical decisions, and increase the scientific knowledge gained from investments by the funders of clinical trials. The recommendations of Sharing Clinical Trial Data will be useful both now and well into the future as improved sharing of data leads to a stronger evidence base for treatment. This book will be of interest to stakeholders across the spectrum of research--from funders, to researchers, to journals, to physicians, and ultimately, to patients.

Download or read book A Manager s Guide to the Design and Conduct of Clinical Trials written by Phillip I. Good and published by John Wiley & Sons. This book was released on 2006-04-28 with total page 272 pages. Available in PDF, EPUB and Kindle. Book excerpt: This newly updated edition of the benchmark guide tocomputer-assisted clinical trials provides a comprehensive primerfor prospective managers. It covers every critical issue of thedesign and conduct of clinical trials, including study design,organization, regulatory agency liaison, data collection andanalysis, as well as recruitment, software, monitoring, andreporting. Keeping the same user-friendly format as the original, this SecondEdition features new examples and the latest developments inregulatory guidelines, such as e-submission procedures andcomputerized direct data acquisition. The new edition also reflectsthe increasing globalization of clinical trial activities, andincludes new information about international standards andprocedures, including the Common Technical Document and CDISCstandards. This step-by-step guide is supported by handy checklists andextracts from submitted protocols. Experienced author andconsultant Phillip Good incorporateshumorous yet instructiveanecdotes to illustrate common pitfalls. Based on the provenindustrial formula of planning, implementing, and finallyperforming essential checks, the book's three sections-"Plan,""Do," and "Check"-includethe following material: * Should the trials be conducted? * Put it in the computer and keep it there * Staffing for success * Designing trials and determining sample size * Budgeting * Recruiting and retaining patients and physicians * Data management * Monitoring the trials * Data analysis * After action review * Exception handling Executive and managerial professionals involved in the design andanalysis of clinical experiments, along with clinical researchassociates, biostatisticians, and students in public health willfind A Manager's Guide an indispensable resource. Praise for the First Edition: ". . . readable, informative and at times witty . . . never stopsbeing concise and well written . . . a book worth a read . .." -Statistics in Medicine "The book is very prescriptive and full of lists and tables withwhich to guide managers in making effective decisions in usingcomputer-assisted clinical trials in pharmaceutical studies."-Technometrics "This book is must-have reading for anyone in the business . .." -Clinical Chemistry

Download or read book Biostatistics in Clinical Trials written by Carol K. Redmond and published by John Wiley & Sons. This book was released on 2001-04-25 with total page 530 pages. Available in PDF, EPUB and Kindle. Book excerpt: The second volume in the Wiley reference series in Biostatistics. Featuring articles from the prestigious Encyclopedia of Biostatistics, many of which have been fully revised and updated to include recent developments, Biostatistics in Clinical Trials also includes up to 25% newly commissioned material reflecting the latest thinking in: Bayesian methods Benefit/risk assessment Cost-effectiveness Ethics Fraud With exceptional contributions from leading experts in academia, government and industry, Biostatistics in Clinical Trials has been designed to complement existing texts by providing extensive, up-to-date coverage and introducing the reader to the research literature. Offering comprehensive coverage of all aspects of clinical trials Biostatistics in Clinical Trials: Includes concise definitions and introductions to numerous concepts found in current literature Discusses the software and textbooks available Uses extensive cross-references helping to facilitate further research and enabling the reader to locate definitions and related concepts Biostatistics in Clinical Trials offers both academics and practitioners from various disciplines and settings, such as universities, the pharmaceutical industry and clinical research organisations, up-to-date information as well as references to assist professionals involved in the design and conduct of clinical trials.

Download or read book Clinical Trials in Neurology written by Roberto J. Guiloff and published by Springer Science & Business Media. This book was released on 2013-03-14 with total page 537 pages. Available in PDF, EPUB and Kindle. Book excerpt: Clinical Trials in Neurology comprehensively tackles the methodology and design of clinical trials in neurological disease. A general section deals with the ethical aspects, drug development and regulatory requirements, basic trial designs and the statistics used. A diseases section tackles specific aspects of disorders, focusing on the relevant ethical issues, outcome variables and experience with large multicentre trials.

Download or read book Statistical Monitoring of Clinical Trials written by Michael A. Proschan and published by Springer Science & Business Media. This book was released on 2006-12-31 with total page 268 pages. Available in PDF, EPUB and Kindle. Book excerpt: The approach taken in this book is, to studies monitored over time, what the Central Limit Theorem is to studies with only one analysis. Just as the Central Limit Theorem shows that test statistics involving very different types of clinical trial outcomes are asymptotically normal, this book shows that the joint distribution of the test statistics at different analysis times is asymptotically multivariate normal with the correlation structure of Brownian motion ("the B-value") – irrespective of the test statistic. Thus, this book offers statisticians an accessible, incremental approach to understanding Brownian motion as related to clinical trials.

Download or read book Developing a Protocol for Observational Comparative Effectiveness Research A User s Guide written by Agency for Health Care Research and Quality (U.S.) and published by Government Printing Office. This book was released on 2013-02-21 with total page 204 pages. Available in PDF, EPUB and Kindle. Book excerpt: This User’s Guide is a resource for investigators and stakeholders who develop and review observational comparative effectiveness research protocols. It explains how to (1) identify key considerations and best practices for research design; (2) build a protocol based on these standards and best practices; and (3) judge the adequacy and completeness of a protocol. Eleven chapters cover all aspects of research design, including: developing study objectives, defining and refining study questions, addressing the heterogeneity of treatment effect, characterizing exposure, selecting a comparator, defining and measuring outcomes, and identifying optimal data sources. Checklists of guidance and key considerations for protocols are provided at the end of each chapter. The User’s Guide was created by researchers affiliated with AHRQ’s Effective Health Care Program, particularly those who participated in AHRQ’s DEcIDE (Developing Evidence to Inform Decisions About Effectiveness) program. Chapters were subject to multiple internal and external independent reviews. More more information, please consult the Agency website: www.effectivehealthcare.ahrq.gov)

Download or read book Design of Observational Studies written by Paul R. Rosenbaum and published by Springer Nature. This book was released on 2020-07-13 with total page 552 pages. Available in PDF, EPUB and Kindle. Book excerpt: This second edition of Design of Observational Studies is both an introduction to statistical inference in observational studies and a detailed discussion of the principles that guide the design of observational studies. An observational study is an empiric investigation of effects caused by treatments when randomized experimentation is unethical or infeasible. Observational studies are common in most fields that study the effects of treatments on people, including medicine, economics, epidemiology, education, psychology, political science and sociology. The quality and strength of evidence provided by an observational study is determined largely by its design. Design of Observational Studies is organized into five parts. Chapters 2, 3, and 5 of Part I cover concisely many of the ideas discussed in Rosenbaum’s Observational Studies (also published by Springer) but in a less technical fashion. Part II discusses the practical aspects of using propensity scores and other tools to create a matched comparison that balances many covariates, and includes an updated chapter on matching in R. In Part III, the concept of design sensitivity is used to appraise the relative ability of competing designs to distinguish treatment effects from biases due to unmeasured covariates. Part IV is new to this edition; it discusses evidence factors and the computerized construction of more than one comparison group. Part V discusses planning the analysis of an observational study, with particular reference to Sir Ronald Fisher’s striking advice for observational studies: "make your theories elaborate." This new edition features updated exploration of causal influence, with four new chapters, a new R package DOS2 designed as a companion for the book, and discussion of several of the latest matching packages for R. In particular, DOS2 allows readers to reproduce many analyses from Design of Observational Studies.

Download or read book The Rise and Fall of Modern Medicine written by James Le Fanu and published by Basic Books. This book was released on 2002-01-18 with total page 448 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the years following World War II, medicine won major battles against smallpox, diphtheria, and polio. In the same period it also produced treatments to control the progress of Parkinson's, rheumatoid arthritis, and schizophrenia. It made realities of open-heart surgery, organ transplants, test-tube babies. Unquestionably, the medical accomplishments of the postwar years stand at the forefront of human endeavor, yet progress in recent decades has slowed nearly to a halt. In this winner of the Los Angeles Times Book Prize, medical doctor and columnist James Le Fanu both surveys the glories of medicine in the postwar years and analyzes the factors that for the past twenty-five years have increasingly widened the gulf between achievement and advancement: the social theories of medicine, ethical issues, and political debates over health care that have hobbled the development of vaccines and discovery of new "miracle" cures. While fully demonstrating the extraordinary progress effected by medical research in the latter half of the twentieth century, Le Fanu also identifies the perils that confront medicine in the twenty-first. 16 pages of black-and-white photographs add to what the Los Angeles Times cited as "a sobering, contrarian challenge" to the "nostrum of medicine as a never-ending font of ‘miracle cures'." "[From] a respected science writer ... important information that ... has been overlooked or ignored by many physicians." —New Republic "Provocative and engrossing and informative." —Houston Chronicle "Marvelously written, meticulously researched ... one of the most thought-provoking and important works to appear in recent years." —Choice

Download or read book Current Catalog written by National Library of Medicine (U.S.) and published by . This book was released on 1992 with total page 666 pages. Available in PDF, EPUB and Kindle. Book excerpt: First multi-year cumulation covers six years: 1965-70.

Download or read book Clinical Hepatology written by G. Csomos and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 481 pages. Available in PDF, EPUB and Kindle. Book excerpt: Hepatology has come of age in the last decades. Biology of the liver has flour ished long before. As the largest homogeneous organ of the body the liver served as useful model in the development of biochemistry and related discip lines. Only gradually were these biological investigations applied to the clinical study of liver disease. This was particularly stimulated by the recognition that in the greater part of the world, the developing countries and what we now call the Third World, liver disease represents a major threat to overall public health. It leads to morbidity and mortality of persons in their productive years from liver cancer, cirrhosis and parasitic disease, particularly, schistosomiasis. Moreover, the growing emphasis on the social impact of diseases focused on disorders of the liver because malnutrition, poverty, and drug addiction contrib ute greatly to their spread. This is compounded by the increase of alcohol abuse, recently on the rise even in the developing countries. Concern with envi ronmental pollution has also raised the interest in liver diseases, in part because the liver acts as a guardian against polluting chemicals and in part because it is considered, possibly to an exaggerated degree, a vulnerable target of such chemicals.

Download or read book National Library of Medicine Current Catalog written by National Library of Medicine (U.S.) and published by . This book was released on 1992 with total page 1332 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Design and Analysis of Sequential Clinical Trials written by John Whitehead and published by . This book was released on 1992 with total page 312 pages. Available in PDF, EPUB and Kindle. Book excerpt: Provides a description of an important class of sequential designs for comparative clinical trials, giving consideration to the practical advantages and disadvantages of each method. This edition features many real examples of clinical trial data as well as simulation results.

Download or read book Permutation Parametric and Bootstrap Tests of Hypotheses written by Phillip I. Good and published by Springer Science & Business Media. This book was released on 2005-12-19 with total page 331 pages. Available in PDF, EPUB and Kindle. Book excerpt: Previous edition sold over 1400 copies worldwide. This new edition includes many more real-world illustrations from biology, business, clinical trials, economics, geology, law, medicine, social science and engineering along with twice the number of exercises.