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Giménez-Duran J J Faculty of Medicine, Department of Preventive Medicine and Public Health, Universitat Autònoma de Barcelona, Bellaterra, Barcelona, - - 2014
The Balearic Islands, Spain, 2010-2012. To assess the completeness of TB surveillance, and to examine observed and estimated incidence rates (IR) compared with the period 2005-2007. The completeness of TB surveillance was assessed using the capture-recapture method. Confidence intervals were calculated using log-linear models. Data sources were records of mandatory ...
Chen Maggie M Amgen Inc., Thousand Oaks, 91320, CA, - - 2014
Proactive evaluation of drug safety with systematic screening and detection is critical to protect patients' safety and important in regulatory approval of new drug indications and postmarketing communications and label renewals. In recent years, quite a few statistical methodologies have been developed to better evaluate drug safety through the life ...
De Cuyper Kathleen K a Faculty of Psychology and Educational Sciences , University of Leuven , - - 2014
We administered the Dutch Multidimensional Perfectionism Scale of Hewitt and Flett (1991, 2004) in a large student sample (N = 959) and performed a confirmatory factor analysis to test the factorial structure proposed by the original authors. The existence of a method factor referring to the negatively keyed items in ...
Valle Denis D School of Forest Resources and Conservation, University of Florida, 136 Newins-Ziegler Hall, Gainesville, FL, 32611, - - 2014
We propose a novel multivariate method to analyse biodiversity data based on the Latent Dirichlet Allocation (LDA) model. LDA, a probabilistic model, reduces assemblages to sets of distinct component communities. It produces easily interpretable results, can represent abrupt and gradual changes in composition, accommodates missing data and allows for coherent ...
Sun Bingrui B Department of Mathematics and Statistics, Memorial University, St. John's, NL, Canada - - 2014
Bivariate multinomial data such as the left and right eyes retinopathy status data are analyzed either by using a joint bivariate probability model or by exploiting certain odds ratio-based association models. However, the joint bivariate probability model yields marginal probabilities, which are complicated functions of marginal and association parameters for ...
Lindqvist Bo Henry BH Department of Mathematical Sciences, Norwegian University of Science and Technology, 7491, Trondheim, Norway, - - 2014
We study residual plots for parametric accelerated failure time (AFT) models, using both standardized residuals and Cox-Snell residuals. Two different approaches are discussed in the case of censored data; adjusting censored residuals by adding a residual time, and using nonparametric exponential regression of non-adjusted censored Cox-Snell residuals. The main object ...
Barra Mathias M Health Services Research Center, Akershus University Hospital, Lørenskog, Akershus, - - 2014
To repair and refine a previously proposed method for statistical analysis of association between migraine and menstruation. Menstrually related migraine (MRM) affects about 20% of female migraineurs in the general population. The exact pathophysiological link from menstruation to migraine is hypothesized to be through fluctuations in female reproductive hormones, but ...
Torabi Mahmoud M Department of Community Health Sciences, University of Manitoba, Winnipeg, Man., - - 2014
Background: Macroscopic geographic variation in the incidence and prevalence of MS is well-recognized. Microscopic geographic variation in the distribution of MS is also recognized, but less well-studied. Most studies have focused on prevalent cases of MS, although studies of variation in disease incidence are more relevant for developing etiologic hypotheses. ...
Gruber Susan S Department of Epidemiology, Harvard School of Public Health, Boston, MA, - - 2014
Inverse probability weights used to fit marginal structural models are typically estimated using logistic regression. However, a data-adaptive procedure may be able to better exploit information available in measured covariates. By combining predictions from multiple algorithms, ensemble learning offers an alternative to logistic regression modeling to further reduce bias in ...
Zhu Haiyuan H Forest Research Institute, Harborside Financial Center, Jersey City, NJ, - - 2014
The number of patient-years needed to treat (NPY NT), also called the event-based number needed to treat, to avoid one additional exacerbation has been reported in recently published respiratory trials, but the confidence intervals are not routinely reported. The challenge of constructing confidence intervals for NPY NT is due to ...
Rhodes Ryan E RE Behavioural Medicine Laboratory, Faculty of Education, University of Victoria, STN CSC, PO Box 3015, Victoria, BC, V8W 3P1, Canada, - - 2014
Regular physical activity (PA) is foundational to human health, yet most people are inactive. A sound understanding of the determinants of PA may be instructive for building interventions and/or identifying critical target groups to promote PA. Most research on PA correlates has been biased by cross-sectional or passive prospective designs ...
Zhou Chaozheng C Institute of Forming Technology & Equipment, Shanghai Jiao Tong University, Shanghai, 200030, - - 2014
Cardiovascular interventional surgery (CIS) training has mainly been performed with fluoroscopic guidance on animals. However, this has potential drawbacks, including from the anatomical differences between animal models and the human body. The purpose of this research is to develop a virtual training platform for inexperienced trainees. The CIS virtual training ...
Blanche Paul P Université Bordeaux Segalen, ISPED, Inserm Research Center U897, F33076 Bordeaux, France; INSERM, ISPED, Centre INSERM U897-Epidémiologie-Biostatistique, F-33000 Bordeaux, France; Department of Biostatistics, University of Copenhagen, DK-1014 Copenhagen K, - - 2014
Thanks to the growing interest in personalized medicine, joint modeling of longitudinal marker and time-to-event data has recently started to be used to derive dynamic individual risk predictions. Individual predictions are called dynamic because they are updated when information on the subject's health profile grows with time. We focus in ...
Blucker Ryan T RT Department of Pediatrics, University of Oklahoma Health Sciences Center, Oklahoma City (Drs Blucker, Cherry, McCaffree, and S. R. Gillaspy, and Mss Hetherington and Kyler); Department of Psychology and Counseling, University of Central Arkansas, Conway (Dr J. A. Gillaspy); and Department of Psychology, University of Windsor, Ontario, Canada (Dr - - 2014
The purpose of this research was to examine the construct validity of scores from the Postpartum Depression Screening Scale administered to mothers of infants in a neonatal intensive care unit. Two samples (n = 385 and n = 110) of mothers with infants in a neonatal intensive care unit in ...
Burke Jeffrey D - - 2014
The importance of irritability, as measured among the symptoms of oppositional defiant disorder (ODD), has dramatically come to the fore in recent years. New diagnostic categories rely on the distinct clinical utility of irritability, and models of psychopathology suggest it plays a key role in explaining developmental pathways within and ...
Altuve Miguel M Grupo de Bioingeniería y Biofísica Aplicada, Universidad Simón Bolívar, Caracas, Venezuela , - - 2014
In this paper, we propose a new online apnea-bradycardia detection scheme that takes into account not only the instantaneous values of time series, but also their temporal evolution. The detector is based on a set of hidden semi-Markov models, representing the temporal evolution of beat-to-beat interval (RR interval) time series. ...
Cortet Marion M Department of Biostatistics, Hospices Civils de Lyon, Lyon, France; University of Lyon, Lyon, France; University of Lyon 1, Villeurbanne, France; UMR 5558, Laboratory of Biometry and Evolutionary Biology, Team of Health and Biostatistics, National Center for Scientific Research, Villeurbanne, - - 2014
Identify women at risk of severe post-partum hemorrhage (PPH) by building a prediction model based on clinical variables available at PPH diagnosis. We analyzed data on a cohort of 7236 women with PPH after vaginal delivery from 106 maternity units. Severe PPH was defined as the loss of more than ...
Han Seungbong S Department of Clinical Epidemiology and Biostatistics, College of Medicine, University of Ulsan, Seoul, Korea - - 2014
In many cohort studies, time to events such as disease recurrence is recorded in an interval-censored format. An important objective is to predict patient outcomes. Clinicians are interested in predictive covariates. Prediction rules based on the receiver operating characteristic curve alone are not related to the survival endpoint. We propose ...
Liu Long L Key Laboratory for Green Process of Chemical Engineering of Xinjiang Bingtuan, School of Chemistry and Chemical Engineering, Shihezi University, Shihezi, 832003, China, - - 2014
Biodesulphurisation was investigated by using Enterobacter sp. D4, which can selectively desulphurise and convert dibenzothiophene into 2-hydroxybiphenyl (2-HBP). The experimental values of growth, substrate consumption and product generation were obtained at 95 % confidence level of the fitted values using three models: Hinshelwood equation, Luedeking-Piret and Luedeking-Piret-like equations. The average error ...
Garcia-Aloy Mar M Biomarkers & Nutrimetabolomic Lab, Nutrition and Food Science Department, XaRTA, INSA, Campus Torribera, Pharmacy Faculty, University of Barcelona, Spain; INGENIO-CONSOLIDER Program, Fun-C-Food CSD2007-063, - - 2014
The aim of the current study was to apply an untargeted metabolomics strategy to characterize a model of cocoa intake biomarkers in a free-living population. An untargeted HPLC-q-ToF-MS based metabolomics approach was applied to human urine from 32 consumers of cocoa or derived products (CC) and 32 matched control subjects ...
Romaniuk Helena - - 2014
Multiple imputation has entered mainstream practice for the analysis of incomplete data. We have used it extensively in a large Australian longitudinal cohort study, the Victorian Adolescent Health Cohort Study (1992-2008). Although we have endeavored to follow best practices, there is little published advice on this, and we have not ...
Shwartz Michael M *Center for Healthcare Organization and Implementation Research, VA Boston Healthcare System (152M) †School of Management ‡School of Public Health §Department of Surgery, School of Medicine, Boston University ∥Center for Healthcare Organization and Implementation Research, Bedford VA Hospital, Bedford, - - 2014
Two approaches are commonly used for identifying high-performing facilities on a performance measure: one, that the facility is in a top quantile (eg, quintile or quartile); and two, that a confidence interval is below (or above) the average of the measure for all facilities. This type of yes/no designation often ...
Cuervo Jesús - - 2014
BackgroundGeneric utility instruments may not fully capture the impact and consequences of urinary problems. Condition-specific preference-based measures, developed from previously validated disease-specific patient-reported outcomes instruments, may add relevant information for economic evaluations. The aim of this study was to develop a condition-specific preference-based measure, the Incontinence Utility Index (IUI), for ...
Rabidoux Scott Michael - - 2014
The vibronic coupling model of Köppel, Domcke, and Cederbaum is a powerful means to understand, predict, and analyze electronic spectra of molecules, especially those which exhibit phenomena that involve breakdown of the Born-Oppenheimer approximation. In this work, we describe a new parallel algorithm for carrying out such calculations. The algorithm ...
Li Jialiang J Department of Statistics and Applied Probability, National University of Singapore, Singapore, 117946, Singapore; Duke-NUS Graduate Medical School, Singapore, 169857, Singapore; Singapore Eye Research Institute, - - 2014
Instrumental variable (IV) methods are popular in non-experimental studies to estimate the causal effects of medical interventions. These approaches allow for the consistent estimation of treatment effects even if important confounding factors are unobserved. Despite the increasing use of these methods, there have been few extensions of IV methods to ...
Moineddin Rahim R Department of Family and Community Medicine, University of Toronto, Toronto, Canada - - 2014
Composite endpoints are commonplace in biomedical research. The complex nature of many health conditions and medical interventions demand that composite endpoints be employed. Different approaches exist for the analysis of composite endpoints. A Monte Carlo simulation study was employed to assess the statistical properties of various regression methods for analyzing ...
Lu Wenbin W Department of Statistics, North Carolina State University, Raleigh, North Carolina, - - 2014
Nested case-control sampling is a popular design for large epidemiological cohort studies due to its cost effectiveness. A number of methods have been developed for the estimation of the proportional hazards model with nested case-control data; however, the evaluation of modeling assumption is less attended. In this article, we propose ...
Out Welmoed A WA 1Graduate School Human Development in Landscapes/Institut für Ur- und Frühgeschichte,Christian-Albrechts-Universität,Johanna-Mestorf-Strasse 2-6,Kiel - - 2014
Micro-morphometry has substantially gained ground in the field of phytolith analysis, but the comparability of results is limited due to the use of different methods. This paper presents a new, user-friendly method based on open-source software (FIJI) that is proposed as a step towards the introduction of a standard method. ...
Zaloumis Sophie G SG Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, University of Melbourne, 207 Bouverie Street, Carlton, Victoria 3010, - - 2014
Methods to examine whether genetic and/or environmental sources can account for the residual variation in ordinal family data usually assume proportional odds. However, standard software to fit the non-proportional odds model to ordinal family data is limited because the correlation structure of family data is more complex than for other ...
Bray Benjamin D BD From the Division of Health and Social Care Research, King's College London, London, United Kingdom (B.D.B., C.D.A.W., A.G.R.); Clinical Effectiveness Unit, Royal College of Physicians, London, United Kingdom (J.C., A.H.); Stroke Unit, St George's NHS Trust, London, United Kingdom (G.C.C.); Stroke Unit, Royal Devon and Exeter NHS Foundation Trust, Exeter, United Kingdom (M.J.); Stroke Unit, Salford Royal NHS Foundation Trust, Salford, United Kingdom (P.J.T.); and National Institute for Health Research Comprehensive Biomedical Research Centre, Guy's and St Thomas' NHS Foundation Trust, London, United Kingdom (C.D.A.W., A.G.R.). - - 2014
Case mix adjustment is required to allow valid comparison of outcomes across care providers. However, there is a lack of externally validated models suitable for use in unselected stroke admissions. We therefore aimed to develop and externally validate prediction models to enable comparison of 30-day post-stroke mortality outcomes using routine ...
Lindgreen Stinus - - 2014
As the use of next-generation sequencing technologies is becoming more widespread, the need for robust software to help with the analysis is growing as well. A key challenge when analyzing sequencing data is the prediction of genotypes from the reads, i.e. correct inference of the underlying DNA sequences that gave ...
Rhodes Kirsty M KM MRC Biostatistics Unit, Cambridge Institute of Public Health, Forvie Site, Robinson Way, Cambridge Biomedical Campus, Cambridge, CB2 0SR, UK. Electronic address: - - 2014
Estimation of between-study heterogeneity is problematic in small meta-analyses. Bayesian meta-analysis is beneficial because it allows incorporation of external evidence on heterogeneity. To facilitate this, we provide empirical evidence on the likely heterogeneity between studies in meta-analyses relating to specific research settings. Our analyses included 6,492 continuous-outcome meta-analyses within the ...
Joseph Royes R Arthritis Research UK Primary Care Centre, Research Institute of Primary Care and Health Sciences, Keele University, Keele, Staffordshire, ST5 5BG, - - 2014
In randomized trials, the primary analysis should be consistent with the intention-to-treat (ITT) principle and should address missing data appropriately to draw valid inferences. This review focuses on current practices relating to the ITT principle and methods to handle missing data in the major musculoskeletal journals. A systematic review of ...
Mikami Yoko - - 2014
The presence and extent of late gadolinium enhancement (LGE) has been associated with adverse events in patients with hypertrophic cardiomyopathy (HCM). Signal intensity (SI) threshold techniques are routinely employed for quantification; Full-Width at Half-Maximum (FWHM) techniques are suggested to provide greater reproducibility than Signal Threshold versus Reference Mean (STRM) techniques, ...
Shan Guogen G Epidemiology and Biostatistics Program, Department of Environmental and Occupational Health, School of Community Health Sciences, University of Nevada Las Vegas, Las Vegas, USA - - 2014
Cohen's kappa coefficient, κ, is a statistical measure of inter-rater agreement or inter-annotator agreement for qualitative items. In this paper, we focus on interval estimation of κ in the case of two raters and binary items. So far, only asymptotic and bootstrap intervals are available for κ due to its ...
Bastien Philippe P L'Oréal Recherche & Innovation, Aulnay, France. IRMA, CNRS UMR 7501, Labex IRMIA, Université de Strasbourg, Strasbourg, France. 3EA3430, INSERM. Laboratoire de Biostatistique, Faculté de Médecine de Strasbourg, Université de Strasbourg, Strasbourg, France. - - 2014
A vast literature from the last decade is devoted to relating gene profiles and subject survival or time to cancer recurrence. Biomarker discovery from high-dimensional data, such as transcriptomic or SNP profiles, is a major challenge in the search for more precise diagnoses. The proportional hazard regression model suggested by ...
Chaimani Anna A Department of Hygiene and Epidemiology, University of Ioannina School of Medicine, Ioannina, - - 2014
Statistical synthesis of research findings via meta-analysis is widely used to assess the relative effectiveness of competing interventions. A series of three papers aimed at familiarising mental health scientists with the key statistical concepts and problems in meta-analysis was recently published in this journal. One paper focused on the selection ...
Aad G G CPPM, Aix-Marseille Université and CNRS/IN2P3, Marseille, - - 2014
This Letter presents the first study of W^{±}W^{±}jj, same-electric-charge diboson production in association with two jets, using 20.3  fb^{-1} of proton-proton collision data at sqrt[s]=8  TeV recorded by the ATLAS detector at the Large Hadron Collider. Events with two reconstructed same-charge leptons (e^{±}e^{±}, e^{±}μ^{±}, and μ^{±}μ^{±}) and two or more jets are ...
Kellen David D Albert-Ludwigs-Universität Freiburg, Freiburg i. Br., - - 2014
The two high threshold model (2HTM) of recognition memory makes strong predictions regarding differences between receiver operating characteristics (ROC) functions across strength manipulations. <citationReference id="cr20-1" rid="c20">Province and Rouder (2012)</citationReference> tested these predictions and showed that the 2HTM provided a better account of the data than a continuous signal detection model ...
Tosh Jonathan J Health Economics and Decision Science, School of Health and Related Research (ScHARR), University of Sheffield, Regent Court, 30 Regent Street, Sheffield, South Yorkshire, S1 4DA, UK, - - 2014
The objective of the work reported in this paper was to critically assess how sequential disease-modifying anti-rheumatic drugs (DMARDs) have been modelled in the context of economic evaluation of the use of DMARDs for treatment of rheumatoid arthritis (RA). A secondary purpose was to identify the methodological challenges of modelling ...
Tu Yu-Kang YK Institute of Epidemiology & Preventive Medicine, College of Public Health, National Taiwan University, Taipei, Taiwan (Y-KT) - - 2014
In the past decade, a new statistical method-network meta-analysis-has been developed to address limitations in traditional pairwise meta-analysis. Network meta-analysis incorporates all available evidence into a general statistical framework for comparisons of multiple treatments. Bayesian network meta-analysis, as proposed by Lu and Ades, also known as "mixed treatments comparisons," provides ...
- - 2014
AN ASSOCIATION between asthma and thunderstorms based on retrospective data has been noted in several papers. This study, however, draws on almost-real-time, anonymised attendance data from 35 emergency departments (EDs) in the UK, and lightning-strike plots from the Met Office.
Wagenmakers Eric-Jan EJ Department of Psychology, University of Amsterdam, Weesperplein 4, 1018 XA, Amsterdam, The Netherlands, - - 2014
The power fallacy refers to the misconception that what holds on average -across an ensemble of hypothetical experiments- also holds for each case individually. According to the fallacy, high-power experiments always yield more informative data than do low-power experiments. Here we expose the fallacy with concrete examples, demonstrating that a ...
Fay Michael P MP National Institute of Allergy and Infectious Diseases, 6700B Rockledge Dr. MSC 7630, Bethesda, Maryland, 20892-7630, - - 2014
We present a simple general method for combining two one-sample confidence procedures to obtain inferences in the two-sample problem. Some applications give striking connections to established methods; for example, combining exact binomial confidence procedures gives new confidence intervals on the difference or ratio of proportions that match inferences using Fisher's ...
Alonso Ariel A Department of Methodology and Statistics, Maastricht University, Maastricht, the - - 2014
The increasing cost of drug development has raised the demand for surrogate endpoints when evaluating new drugs in clinical trials. However, over the years, it has become clear that surrogate endpoints need to be statistically evaluated and deemed valid, before they can be used as substitutes of "true" endpoints in ...
Hemani Gibran G 1] Queensland Brain Institute, University of Queensland, Brisbane, Queensland 4072, Australia [2] University of Queensland Diamantina Institute, University of Queensland, Princess Alexandra Hospital, Brisbane, Queensland 4072, - - 2014
Replying to A. R. Wood et al. 514, http://dx.doi.org/10.1038/nature13691 (2014).We thank Wood et al. for their interesting observations and although their proposed mechanism does not explain all our reported results, we acknowledge that alternative mechanisms could be behind the observation of epistatic signals. Although we replicate our results in large, ...
Joshi Shreedhar S SS Department of Cardiac Anaesthesiology, Sri Jayadeva Institute of Cardiovascular Sciences and Research, Bengaluru, Karnataka, - - 2014
Aims and Objectives: To validate Aristotle basic complexity and Aristotle comprehensive complexity (ABC and ACC) and risk adjustment in congenital heart surgery-1 (RACHS-1) prediction models for in hospital mortality after surgery for congenital heart disease in a single surgical unit. Materials and Methods: Patients younger than 18 years, who had ...
Bhatnagar Nidhi N Department of Community Medicine, School of Public Health, Post Graduate Institute of Medical Education and Research, Chandigarh, - - 2014
Randomized control trials and its meta-analysis has occupied the pinnacle in levels of evidence available for research. However, there were several limitations of these trials. Network meta-analysis (NMA) is a recent tool for evidence-based medicine that draws strength from direct and indirect evidence generated from randomized control trials. It facilitates ...
Lefering Rolf R Institute for Research in Operative Medicine (IFOM), University of Witten/Herdecke, Ostmerheimer Str. 200 (Building 38), 51109 Cologne, Germany. Electronic address: - - 2014
The present paper is a description and summary of methods used in non-randomised cohort data where the comparability of the study groups usually is not granted. Such study groups are formed by a diagnostic or therapeutic intervention, or by other characteristics of the patient or the treatment environment. This is ...
Lai Zhihui - - 2014
In this brief, multilinear sparse principal component analysis (MSPCA) is proposed for feature extraction from the tensor data. MSPCA can be viewed as a further extension of the classical principal component analysis (PCA), sparse PCA (SPCA) and the recently proposed multilinear PCA (MPCA). The key operation of MSPCA is to ...
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