Multilevel modeling versus cross-sectional analysis for assessing the longitudinal tracking of cardiovascular risk factors over time.

abstract：:In contrast to other models for ordinal data, the continuation ratio model can be fitted with standard statistical software. This makes it particularly appropriate for large clinical trials with ordinal response variables. In addition, when the trials are longitudinal, this model can be applied to individual responses...

journal_title：Statistics in medicine

authors： Lindsey JK,Jones B,Ebbutt AF

更新日期：1997-12-30 00:00:00

abstract：:In medical research, a two-phase study is often used for the estimation of the area under the receiver operating characteristic curve (AUC) of a diagnostic test. However, such a design introduces verification bias. One of the methods to correct verification bias is inverse probability weighting (IPW). Since the probab...

journal_title：Statistics in medicine

authors： Wu Y

更新日期：2020-11-30 00:00:00

abstract：:In biomedical studies and clinical trials, repeated measures are often subject to some upper and/or lower limits of detection. Hence, the responses are either left or right censored. A complication arises when more than one series of responses is repeatedly collected on each subject at irregular intervals over a perio...

journal_title：Statistics in medicine

authors： Lachos VH,A Matos L,Castro LM,Chen MH

更新日期：2019-03-15 00:00:00

abstract：:We suggest measures to quantify the degrees of necessity and of sufficiency of prognostic factors for dichotomous and for survival outcomes. A cause, represented by certain values of prognostic factors, is considered necessary for an event if, without the cause, the event cannot develop. It is considered sufficient fo...

journal_title：Statistics in medicine

authors： Gleiss A,Schemper M

更新日期：2019-10-15 00:00:00

abstract：:In Part I we presented a covariance structure model for analysing measurement error in the assessment of nitrogen intake. In this paper we include data on urine nitrogen excretion which allows a critical assessment of the model proposed. Inclusion of urine nitrogen data produces more pessimistic estimates of the quali...

journal_title：Statistics in medicine

authors： Plummer M,Clayton D

更新日期：1993-05-30 00:00:00

abstract：:In the comparison of two or more treatment groups to a control group, consider a study with non-decreasing repeated measurements of the same characteristic taken over a common set of time points for each subject. Based on the vector of possibly incomplete responses from each subject, this paper considers asymptoticall...

journal_title：Statistics in medicine

authors： Davis CS

更新日期：1996-12-15 00:00:00

abstract：:Many different methods have been proposed for the analysis of cluster randomized trials (CRTs) over the last 30 years. However, the evaluation of methods on overdispersed count data has been based mostly on the comparison of results using empiric data; i.e. when the true model parameters are not known. In this study, ...

journal_title：Statistics in medicine

authors： Durán Pacheco G,Hattendorf J,Colford JM Jr,Mäusezahl D,Smith T

更新日期：2009-10-30 00:00:00

abstract：:Meta-analysis to investigate the joint effect of multiple factors in the aetiology of a disease is of increasing importance in epidemiology. This task is often challenging in practice, because studies typically concentrate on studying the effect of only one exposure, sometimes may report the interaction between two ex...

journal_title：Statistics in medicine

authors： Salanti G,Higgins JP,White IR

更新日期：2006-12-30 00:00:00

abstract：:Data on alcohol availability and problems in all cities in Los Angeles County were collected from several different sources and linked together to form a Local Alcohol Availability Database (LAAD). The two major purposes of the project are to provide a city-level alcohol availability and alcohol-related problems datab...

journal_title：Statistics in medicine

authors： MacKinnon DP,Scribner R,Taft KA

更新日期：1995-03-15 00:00:00

abstract：:This paper describes the Stoke Index which has been designed to give a global measure of disease activity in rheumatoid arthritis. The index is based on two objective laboratory measurements, one subjective and two semi-objective clinical measurements, chosen from 13 measurements using clinical judgement. Variable sel...

journal_title：Statistics in medicine

authors： Jones PW,Ziade MF,Davis MJ,Dawes PT

更新日期：1993-06-30 00:00:00

abstract：:Researchers in clinical science and bioinformatics frequently aim to learn which of a set of candidate biomarkers is important in determining a given outcome, and to rank the contributions of the candidates accordingly. This article introduces a new approach to research questions of this type, based on targeted maximu...

journal_title：Statistics in medicine

authors： Bembom O,Petersen ML,Rhee SY,Fessel WJ,Sinisi SE,Shafer RW,van der Laan MJ

更新日期：2009-01-15 00:00:00

abstract：:Standard methods for analysing survival data or case-control data normally concern factors affecting a subject as a whole. However, in a study of a condition that might develop in one or both of a pair of bodily organs information on response and on covariates may be available for each separately. This information can...

journal_title：Statistics in medicine

authors： Whitehead J,Dorse C

更新日期：1988-05-01 00:00:00

abstract：:Although there are many models which are used to calculate the health benefits (and thus the cost-effectiveness) of vaccination programmes, they can be divided into two groups: those which assume a constant force of infection, that is a constant per-susceptible rate of infection; and those which assume that the force ...

journal_title：Statistics in medicine

authors： Edmunds WJ,Medley GF,Nokes DJ

更新日期：1999-12-15 00:00:00

abstract：:Case-control studies are prone to low power for testing gene-environment interactions (GXE) given the need for a sufficient number of individuals on each strata of disease, gene, and environment. We propose a new study design to increase power by strategically pooling biospecimens. Pooling biospecimens allows us to in...

journal_title：Statistics in medicine

authors： Danaher MR,Schisterman EF,Roy A,Albert PS

更新日期：2012-11-20 00:00:00

abstract：:Hierarchical regression analysis holds much promise for epidemiologic analysis, but has as yet seen limited application because of lack of easily used software and the relatively lengthy run times of preferred fitting methods (such as true maximum likelihood and Bayesian approaches). This paper compares three relative...

journal_title：Statistics in medicine

authors： Greenland S

更新日期：1997-03-15 00:00:00

abstract：:The randomized clinical trial, LU19, conducted by the Medical Research Council Lung Cancer Working Party, was designed to compare ACE (doxorubicin, cyclophosphamide and etoposide) chemotherapy plus G-CSF (granulocyte colony-stimulating factor) at 2-week intervals versus ACE chemotherapy alone at standard 3-week interv...

journal_title：Statistics in medicine

authors： Qian W,Parmar MK,Sambrook RJ,Fayers PM,Girling DJ,Stephens RJ

更新日期：2000-10-15 00:00:00

abstract：:The concept of broad sense agreement (BSA) has recently been proposed for studying the relationship between a continuous measurement and an ordinal measurement. They developed a nonparametric procedure for estimating the BSA index, which is only applicable to completely observed data. In this work, we consider the pro...

journal_title：Statistics in medicine

authors： Dai T,Guo Y,Peng L,Manatunga A

更新日期：2020-06-30 00:00:00

abstract：:An important problem in oncology is comparing chemotherapy (chemo) agents in terms of their effects on survival or progression-free survival time. When the goal is to evaluate individual agents, a difficulty commonly encountered with observational data is that many patients receive a chemo combination including two or...

journal_title：Statistics in medicine

authors： Thall PF,Liu DD,Berrak SG,Wolff JE

更新日期：2011-07-10 00:00:00

abstract：:Delay in the outcome variable is challenging for outcome-adaptive randomization, as it creates a lag between the number of subjects accrued and the information known at the time of the analysis. Motivated by a real-life pediatric ulcerative colitis trial, we consider a case where a short-term predictor is available fo...

journal_title：Statistics in medicine

authors： Kim MO,Liu C,Hu F,Lee JJ

更新日期：2014-10-15 00:00:00

abstract：:In case-control studies, the Cochran-Armitage (CA) trend test is powerful for detection of an association between a risk allele and a marker. To apply this test, a score should be assigned to the genotypes based on the genetic model. When the underlying genetic model is unknown, the trend test statistic is a function ...

journal_title：Statistics in medicine

authors： Zheng G

更新日期：2003-08-30 00:00:00

abstract：:The identification of counties burdened by exceptionally high rates of mortality is a fundamental step in the development of state-based intervention and prevention strategies. However, the estimation of rates from small geographic areas presents special problems, especially for rare events. This paper compares the us...

journal_title：Statistics in medicine

authors： Stevenson JM,Olson DR

更新日期：1993-02-01 00:00:00

abstract：:Exploring the possible reasons for heterogeneity between studies is an important aspect of conducting a meta-analysis. This paper compares a number of methods which can be used to investigate whether a particular covariate, with a value defined for each study in the meta-analysis, explains any heterogeneity. The main ...

journal_title：Statistics in medicine

authors： Thompson SG,Sharp SJ

更新日期：1999-10-30 00:00:00

abstract：:Longitudinal studies are often concerned with estimating the recurrence rate of a non-fatal event. In many cases, only the total number of events occurring during successive time intervals is known. We compared a mixed Poisson-gamma regression method proposed by Thall and a quasi-likelihood method proposed by Zeger an...

journal_title：Statistics in medicine

authors： Stukel TA

更新日期：1993-07-30 00:00:00

abstract：:In many chronic diseases, therapy aims to prevent or reduce the frequency of episodes of a disease manifestation, for example cardiac ischaemic episodes or epileptic seizures. Entry criteria for clinical trials typically include a minimum number of episodes within a baseline period, and regression to the mean should b...

journal_title：Statistics in medicine

authors： McMahon RP,Proschan M,Geller NL,Stone PH,Sopko G

更新日期：1994-04-30 00:00:00

abstract：:Recurrent event data are commonly encountered in health-related longitudinal studies. In this paper time-to-events models for recurrent event data are studied with non-informative and informative censorings. In statistical literature, the risk set methods have been confirmed to serve as an appropriate and efficient ap...

journal_title：Statistics in medicine

authors： Wang MC,Chiang CT

更新日期：2002-02-15 00:00:00

abstract：:Clinical studies that involve the recording of two or more distinct and well-defined events on each subject give rise to multiple event data. Treatment comparisons are usually reported in univariate analyses of time to first event or number of events observed. However, this approach may not uncover the 'full story' of...

journal_title：Statistics in medicine

authors： Barai U,Teoh N

更新日期：1997-04-30 00:00:00

abstract：:Generalized linear models may be extended in several ways. This paper describes five such extensions: (i) generalized additive models; (ii) the use of quasi-likelihood; (iii) joint modelling of mean and dispersion; (iv) introduction of extra random components to give hierarchical generalized linear models; (v) modelli...

journal_title：Statistics in medicine

authors： Nelder JA

更新日期：1998-12-15 00:00:00

abstract：:Spatial scan statistics are widely used for count data to detect geographical disease clusters of high or low incidence, mortality or prevalence and to evaluate their statistical significance. Some data are ordinal or continuous in nature, however, so that it is necessary to dichotomize the data to use a traditional s...

journal_title：Statistics in medicine

authors： Jung I,Kulldorff M,Klassen AC

更新日期：2007-03-30 00:00:00

abstract：:In recent years, quality control charts have been increasingly applied in the healthcare environment, for example, to monitor surgical performance. Risk-adjusted cumulative (CUSUM) charts that utilize risk scores like the Parsonnet score to estimate the probability of death of a patient from an operation turn out to b...

journal_title：Statistics in medicine

authors： Knoth S,Wittenberg P,Gan FF

更新日期：2019-05-30 00:00:00

abstract：:For time-to-event outcomes, a rich literature exists on the bias introduced by covariate measurement error in regression models, such as the Cox model, and methods of analysis to address this bias. By comparison, less attention has been given to understanding the impact or addressing errors in the failure time outcome...

journal_title：Statistics in medicine

authors： Oh EJ,Shepherd BE,Lumley T,Shaw PA

更新日期：2018-04-15 00:00:00