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Statistical errors in modern medical research

Iwao Kuwajima
Since a concept of Evidence-based Medicine appeared in medical field in 1991, modern medical treatment have been remarkably changed.However, delusive belief of EBM without criticism has brought negative aspect, such as utilization of EBM by companies as a tool of promotion of drug or medical device.Although most of clinical trials were financially supported by drug companies. result of clinical trial does not always ended in favor of test drug or device. When negative results appeared, various way were taken by industry such as usage of SPIN, emphasizing secondary endpoint...
September 2016: Journal of Hypertension
Iwao Kuwajima
Since a concept of Evidence-based Medicine appeared in medical field in 1991, modern medical treatment have been remarkably changed.However, delusive belief of EBM without criticism has brought negative aspect, such as utilization of EBM by companies as a tool of promotion of drug or medical device.Although most of clinical trials were financially supported by drug companies. result of clinical trial does not always ended in favor of test drug or device. When negative results appeared, various way were taken by industry such as usage of SPIN, emphasizing secondary endpoint...
September 2016: Journal of Hypertension
Brett G Olivier, Maciej J Swat, Martijn J Moné
Modeling is an integral component of modern biology. In this chapter we look into the role of the model, as it pertains to Systems Medicine, and the software that is required to instantiate and run it. We do this by comparing the development, implementation, and characteristics of tools that have been developed to work with two divergent methodologies: Systems Biology and Pharmacometrics. From the Systems Biology perspective we consider the concept of "Software as a Medical Device" and what this may imply for the migration of research-oriented, simulation software into the domain of human health...
2016: Methods in Molecular Biology
Lau Caspar Thygesen, Annette Kjær Ersbøll
Studies based on databases, medical records and registers are used extensively today in epidemiological research. Despite the increasing use, no developed methodological literature on use and evaluation of population-based registers is available, even though data collection in register-based studies differs from researcher-collected data, all persons in a population are available and traditional statistical analyses focusing on sampling error as the main source of uncertainty may not be relevant. We present the main strengths and limitations of register-based studies, biases especially important in register-based studies and methods for evaluating completeness and validity of registers...
August 2014: European Journal of Epidemiology
Nian-Sheng Tang, Bo Zhang, Hu-Qiong Li
Stratified matched-pair studies are often designed for adjusting stratification factors in modern medical researches. This article investigates a homogeneity test of differences between two correlated proportions in stratified matched-pair studies. We propose three test procedures, including an asymptotic test, bootstrap test, and multiple comparison procedures, and determine sample size requirements for such tests in a stratified matched-pair study. Simulation studies are conducted to evaluate the performance of the three test procedures and the accuracy of our derived sample size formulas...
2013: Journal of Biopharmaceutical Statistics
Bronislava Bashinskaya, Brian V Nahed, Navid Redjal, Kristopher T Kahle, Brian P Walcott
BACKGROUND: Peptic ulcer disease can lead to serious complications including massive hemorrhage or bowel perforation. The modern treatment of peptic ulcer disease has transitioned from the control of gastric acid secretion to include antibiotic therapy in light of the identification of Helicobacter pylori as a causative infectious organism. We sought to determine trends related to this discovery by using a national database. MATERIALS AND METHODS: Patient discharges with peptic ulcer disease and associated sequelae were queried from the Nationwide Inpatient Sample, 1993 to 2007, under the auspices of a data user agreement...
October 2011: Journal of Global Infectious Diseases
Aileen B Dequito, Peter G M Mol, Jasperien E van Doormaal, Rianne J Zaal, Patricia M L A van den Bemt, Flora M Haaijer-Ruskamp, Jos G W Kosterink
BACKGROUND: Medication safety research and clinical pharmacy practice today is primarily focused on managing preventable adverse drug events (pADEs). Determinants of both pADEs and non-preventable adverse drug reactions (ADRs) have been identified. However, relatively little is known on the overlap between these determinants and the balance of preventable and non-preventable harm inpatients experience in modern computerized hospitals. OBJECTIVE: The aim of this study was to analyse the prevalence of pADEs and non-preventable ADRs as well as the determinants, including multimorbidity, of these ADEs, i...
November 1, 2011: Drug Safety: An International Journal of Medical Toxicology and Drug Experience
Peter McCulloch, Ken Catchpole
BACKGROUND: Research estimates of inadvertent harm to patients undergoing modern healthcare demonstrate a serious problem. Much attention has been paid to analysis of the causes of error and harm, but researchers have typically focussed either on human interaction and communication or on systems design, without fully considering the other components. Existing models for analysing harm are principally derived from theory and the analysis of individual incidents, and their practical value is often limited by the assumption that identifying causal factors automatically suggests solutions...
2011: BMC Surgery
Nian-Sheng Tang, Hui-Qiong Li, Man-Lai Tang
A stratified matched-pair study is often designed for adjusting a confounding effect or effect of different trails/centers/ groups in modern medical studies. The relative risk is one of the most frequently used indices in comparing efficiency of two treatments in clinical trials. In this paper, we propose seven confidence interval estimators for the common relative risk and three simultaneous confidence interval estimators for the relative risks in stratified matched-pair designs. The performance of the proposed methods is evaluated with respect to their type I error rates, powers, coverage probabilities, and expected widths...
January 15, 2010: Statistics in Medicine
Maria Vardaki, Haralambos Papageorgiou, Fragkiskos Pentaris
We introduce a statistical, process-oriented metadata model to describe the process of medical research data collection, management, results analysis and dissemination. Our approach explicitly provides a structure for pieces of information used in Clinical Study Data Management Systems, enabling a more active role for any associated metadata. Using the object-oriented paradigm, we describe the classes of our model that participate during the design of a clinical trial and the subsequent collection and management of the relevant data...
August 2009: Computer Methods and Programs in Biomedicine
Carl V Phillips, Richard F MacLehose, Jay S Kaufman
In 2004, Garcia-Berthou and Alcaraz published "Incongruence between test statistics and P values in medical papers," a critique of statistical errors that received a tremendous amount of attention. One of their observations was that the final reported digit of p-values in articles published in the journal Nature departed substantially from the uniform distribution that they suggested should be expected. In 2006, Jeng critiqued that critique, observing that the statistical analysis of those terminal digits had been based on comparing the actual distribution to a uniform continuous distribution, when digits obviously are discretely distributed...
2008: Emerging Themes in Epidemiology
Gregory W Daniel, Daniel C Malone
BACKGROUND: The Medicare Modernization Act of 2003 requires drug plan sponsors to provide medication therapy management programs (MTMPs) to beneficiaries with (1) drug expenditures above $4,000, (2) multiple comorbidities, and (3) multiple prescription drugs. The Medical Expenditure Panel Survey (MEPS) is a national probability survey conducted annually by the Agency for Healthcare Research and Quality and the National Center for Health Statistics to provide nationally representative estimates of health care use, expenditures, sources of payments, and insurance coverage for the U...
March 2007: Journal of Managed Care Pharmacy: JMCP
James M Crawford
Pathology is both a medical specialty and an investigative scientific discipline, concerned with understanding the essential nature of human disease. Ultimately, pathology is accountable as well, as measured by the accuracy of our diagnoses and the resultant patient care outcomes. As such, we must consider the evidence base underlying our practices. Within the realm of Laboratory Medicine, extensive attention has been given to testing accuracy and precision. Critical examination of the evidence base supporting the clinical use of specific laboratory tests or technologies is a separate endeavor, to which specific attention must be given...
February 2007: Laboratory Investigation; a Journal of Technical Methods and Pathology
Mitchell S Cappell
While Nazism is almost universally recognized as a great evil, control of science and medicine by the totalitarian Nazi state might be viewed as increasing efficiency. Scientific methods are applied to semiquantitatively analyze the effects of Nazism on medical progress in gastroenterology to document its pernicious effects, and to honor outstanding gastroenterologists persecuted or murdered by the Nazis. This is a retrospective, quasi-case-controlled study. To disprove the null hypothesis that Nazism was efficient, retarded progress in gastroenterology is demonstrated by (1) enumerating the loss to Nazi Germany from 1933 to 1944 due to violent death, incarceration, or forced exile of key researchers in gastroenterology, defined by authorship of at least one book or 10 articles in peer-reviewed journals or other outstanding scholarship; (2) demonstrating a statistically significantly greater loss in Nazi Germany than in non-Nazi (Weimar German Republic from 1921 to 1932) or anti-Nazi (democratic America from 1933 to 1944) control groups; and (3) demonstrating that each loss was directly due to Nazism (murder, incarceration, or exile due to documented threat of violence/death or revocation of medical license)...
June 2006: Digestive Diseases and Sciences
Catherine M Tighe, Maria Woloshynowych, Ruth Brown, Bob Wears, Charles Vincent
Greater focus is needed on improving patient safety in modern healthcare systems and the first step to achieving this is to reliably identify the safety issues arising in healthcare. Research has shown the accident and emergency (A&E) department to be a particularly problematic environment where safety is a concern due to various factors, such as the range, nature and urgency of presenting conditions and the high turnover of patients. As in all healthcare environments clinical incident reporting in A&E is an important tool for detecting safety issues which can result in identifying solutions, learning from error and enhancing patient safety...
January 2006: Accident and Emergency Nursing
Weichung J Shih, Peter Ouyang, Hui Quan, Yong Lin, Bart Michiels, Luc Bijnens
The U.S. Food and Drug Administration (FDA) Modernization Act of 1997 has a Section (No. 112) entitled 'Expediting Study and Approval of Fast Track Drugs' (the Act). In 1998, the FDA issued a 'Guidance for Industry: the Fast Track Drug Development Programs' (the FTDD programmes) to meet the requirement of the Act. The purpose of FTDD programmes is to 'facilitate the development and expedite the review of new drugs that are intended to treat serious or life-threatening conditions and that demonstrate the potential to address unmet medical needs'...
March 15, 2003: Statistics in Medicine
M Spála
Contemporary pathophysiology is essentially based upon three principal pillars of support: First the experimental method (formulated by Cl. Bernard); second experimental design (proposed by R. A. Fisher); and finally, present-day information resources, which are easily accessible in sophisticated databases, following the so-called information explosion. These three underlying principles, sensitively interrelated, should be employed appropriately when engaging in pathophysiological research or education. Three points of support invariably offer stable equilibrium, as does a tripod, and it would be an error a priori to attempt to support research work exclusively on high-tech methodology, or overreliance on statistical software, or pseudo-abundance of citations from journals enjoying a high impact factor, whilst lacking significant balancing support from either of the other two legs of the tripod--or indeed other sources altogether...
1999: Sborník Lékar̆ský
J A Teresi, M Kleinman, K Ocepek-Welikson
Cognitive screening tests and items have been found to perform differently across groups that differ in terms of education, ethnicity and race. Despite the profound implications that such bias holds for studies in the epidemiology of dementia, little research has been conducted in this area. Using the methods of modern psychometric theory (in addition to those of classical test theory), we examined the performance of the Attention subscale of the Mattis Dementia Rating Scale. Several item response theory models, including the two- and three-parameter dichotomous response logistic model, as well as a polytomous response model were compared...
June 15, 2000: Statistics in Medicine
S N Goodman
An important problem exists in the interpretation of modern medical research data: Biological understanding and previous research play little formal role in the interpretation of quantitative results. This phenomenon is manifest in the discussion sections of research articles and ultimately can affect the reliability of conclusions. The standard statistical approach has created this situation by promoting the illusion that conclusions can be produced with certain "error rates," without consideration of information from outside the experiment...
June 15, 1999: Annals of Internal Medicine
A Gouveia-Oliveira
Statistics is the science that studies variability in all its forms and, in essence, is an instrument that allows us to analyze variable phenomena and detect small, but nevertheless important, differences. The instrumental character of this science made Statistics a fundamental tool for the study of biological and clinical phenomena, but the purpose of this discussion is to focus on the fact that Statistics, either directly or indirectly, is presently the basis of virtually all medical decision-making processes and, consequently, has had a major influence on clinical practice itself...
October 1996: Acta Médica Portuguesa
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