Comparison of methods for estimating the effect of salvage therapy in prostate cancer when treatment is given by indication.

abstract：:The application of Bayesian hierarchical models to measure spatial effects in time to event data has not been widely reported. This case study aims to estimate the effect of area of residence on waiting times to coronary artery bypass graft (CABG) and to assess the role of important individual specific covariates (age...

journal_title：Statistics in medicine

authors： Crook AM,Knorr-Held L,Hemingway H

更新日期：2003-09-30 00:00:00

abstract：:We investigated interobserver variation between three physician readers in the independent classification of chest radiographs from 1771 taconite workers for pneumoconiosis. We analysed variation with a general methodology for the analysis of categorical data, and quantified interobserver agreement in terms of kappa-t...

journal_title：Statistics in medicine

authors： Musch DC,Landis JR,Higgins IT,Gilson JC,Jones RN

更新日期：1984-01-01 00:00:00

abstract：:The "some invalid, some valid instrumental variable estimator" (sisVIVE) is a lasso-based method for instrumental variables (IVs) regression of outcome on an exposure. In principle, sisVIVE is robust to some of the IVs in the analysis being invalid, in the sense of being related to the outcome variable through pathway...

journal_title：Statistics in medicine

authors： Bao Y,Clarke PS,Smart M,Kumari M

更新日期：2019-04-30 00:00:00

abstract：:Immigration-death models are proposed to analyse the infection dynamics in longitudinal studies of panels of heavily parasitized human hosts where parasites have been typed at regular intervals by PCR. Immigration refers to the acquisition of a new parasitic genotype, occurring at rate lambda, and death refers to the ...

journal_title：Statistics in medicine

authors： Sama W,Owusu-Agyei S,Felger I,Vounatsou P,Smith T

更新日期：2005-11-15 00:00:00

abstract：:The explanation of heterogeneity plays an important role in meta-analysis. The random effects meta-regression model allows the inclusion of trial-specific covariates which may explain a part of the heterogeneity. We examine the commonly used tests on the parameters in the random effects meta-regression with one covari...

journal_title：Statistics in medicine

authors： Knapp G,Hartung J

更新日期：2003-09-15 00:00:00

abstract：:We have developed a method to longitudinally classify subjects into two or more prognostic groups using longitudinally observed values of markers related to the prognosis. We assume the availability of a training data set where the subjects' allocation into the prognostic group is known. The proposed method proceeds i...

journal_title：Statistics in medicine

authors： Komárek A,Hansen BE,Kuiper EM,van Buuren HR,Lesaffre E

更新日期：2010-12-30 00:00:00

abstract：:The power prior has been widely used in many applications covering a large number of disciplines. The power prior is intended to be an informative prior constructed from historical data. It has been used in clinical trials, genetics, health care, psychology, environmental health, engineering, economics, and business. ...

journal_title：Statistics in medicine

authors： Ibrahim JG,Chen MH,Gwon Y,Chen F

更新日期：2015-12-10 00:00:00

abstract：:We examine different methods to pool binary outcomes used both in parallel and cross-over trials. Odds ratio (OR) estimators obtained from joint conditional probabilities in cross-over trials, such as the Mantel-Haenszel and Peto methods, are compared to an OR estimator using marginal results of cross-over trials. Whe...

journal_title：Statistics in medicine

authors： Curtin F,Elbourne D,Altman DG

更新日期：2002-08-15 00:00:00

abstract：:In many medical and health studies, high-dimensional data are often encountered. Principal component analysis (PCA) is a commonly used technique to reduce such data to a few components that includes most of the information provided by the original data. However, PCA is known to be very sensitive to some abnormal obser...

journal_title：Statistics in medicine

authors： Fung WK,Gu H,Xiang L,Yau KK

更新日期：2007-06-15 00:00:00

abstract：:Zero-inflated Poisson regression is a popular tool used to analyze data with excessive zeros. Although much work has already been performed to fit zero-inflated data, most models heavily depend on special features of the individual data. To be specific, this means that there is a sizable group of respondents who endor...

journal_title：Statistics in medicine

authors： Lin TH,Tsai MH

更新日期：2013-04-30 00:00:00

abstract：:The estimation of attributable risk in the presence of confounding and effect modification is studied in this paper. Different adjustment methods for the attributable risk are reviewed. The results of a stimulation study comparing these methods under the unrestricted multinomial sampling model are reported. From the s...

journal_title：Statistics in medicine

authors： Gefeller O

更新日期：1992-12-01 00:00:00

abstract：:With the increasing availability of detailed clinical information, there is optimism that treatment choices can be selectively directed to those individuals most likely to benefit. While standard clinical trials can establish whether a treatment appears to be effective on average, subsequent work is needed to determin...

journal_title：Statistics in medicine

authors： Sitlani CM,Heagerty PJ

更新日期：2014-07-30 00:00:00

abstract：:We propose to use a very simple model to test whether a cancer cluster is due to chance alone. We focus on the acute childhood leukaemia cluster in Columbus, Ohio. In 1975, 12 leukaemia cases were observed in Columbus while the expected number is 6 cases per year. According to our simple model, the probability of such...

journal_title：Statistics in medicine

authors： Schinazi RB

更新日期：2000-08-30 00:00:00

abstract：:Conditional power based on summary statistic by comparing outcomes (such as the sample mean) directly between 2 groups is a convenient tool for decision making in randomized controlled trial studies. In this paper, we extend the traditional summary statistic-based conditional power with a general model-based assessmen...

journal_title：Statistics in medicine

authors： Zou B,Cai J,Koch GG,Zhou H,Zou F

更新日期：2017-12-30 00:00:00

abstract：:Patients who switch treatment groups in randomized clinical trials can cause problems in the interpretation of the results. Although the intention-to-treat method is recognized as being the most reliable analysis, it may result in an underestimate of the treatment effect if there have been patients who switch treatmen...

journal_title：Statistics in medicine

authors： Law MG,Kaldor JM

更新日期：1996-10-15 00:00:00

abstract：:In lifetime data, like cancer studies, there may be long term survivors, which lead to heavy censoring at the end of the follow-up period. Since a standard survival model is not appropriate to handle these data, a cure model is needed. In the literature, covariate hypothesis tests for cure models are limited to parame...

journal_title：Statistics in medicine

authors： López-Cheda A,Jácome MA,Van Keilegom I,Cao R

更新日期：2020-07-30 00:00:00

abstract：:Rao proposed and compared several approaches for predicting future observations in a growth curve model. The assessment of associated prediction efficiency for different prediction methods were evaluated by Cross-Validation Assessment Error (CVAE). He used three data sets, each with a limited number of subjects (13-27...

journal_title：Statistics in medicine

authors： Tian JJ,Shukla R,Buncher CR

更新日期：1994-11-15 00:00:00

abstract：:Surrogate endpoint validation has been well established by the meta-analytical correlation-based approach as outlined in the seminal work of Buyse et al. (Biostatistics, 2000). Surrogacy can be assumed if strong associations on individual and study levels can be demonstrated. Alternatively, if an effect on a true endp...

journal_title：Statistics in medicine

authors： Schürmann C,Sieben W

更新日期：2016-03-30 00:00:00

abstract：:The one-step (Peto) method for obtaining pooled effect estimates can yield extremely biased results when applied to unbalanced data. Even for balanced studies, the one-step estimate may incorporate an unacceptable degree of bias. In place of the one-step estimate, we recommend use of ordinary Mantel-Haenszel, weighted...

journal_title：Statistics in medicine

authors： Greenland S,Salvan A

更新日期：1990-03-01 00:00:00

abstract：:We study prevalence-dependent diagnostic accuracy measures, specifically, positive and negative predictive values. These measures permit an assessment of the clinical utility of diagnostic tests across populations with different disease prevalences. In many cases, prevalence may not be known with certainty and the eva...

journal_title：Statistics in medicine

authors： Li J,Fine JP,Safdar N

更新日期：2007-07-30 00:00:00

abstract：:Having a surrogate for a definitive endpoint in a clinical trial can sometimes be useful when it is impractical, invasive or very time consuming to obtain the definitive endpoint. This paper discusses methods for assessing whether the surrogate-endpoint results of a trial can be used in place of definitive-endpoint re...

journal_title：Statistics in medicine

authors： Korn EL,Albert PS,McShane LM

更新日期：2005-01-30 00:00:00

abstract：:Testing the equality of 2 proportions for a control group versus a treatment group is a well-researched statistical problem. In some settings, there may be strong historical data that allow one to reliably expect that the control proportion is one, or nearly so. While one-sample tests or comparisons to historical cont...

journal_title：Statistics in medicine

authors： Gabriel EE,Nason M,Fay MP,Follmann DA

更新日期：2018-03-30 00:00:00

abstract：:Comparative effectiveness research represents the kind of research that arguably more directly affects clinical practice and policy. It includes observational studies, clinical trials, and systematic syntheses of existing literature. In this commentary, I argue for the ongoing and critical role of randomization in com...

journal_title：Statistics in medicine

authors： Lauer MS

更新日期：2012-11-10 00:00:00

abstract：:The stability-controlled quasi-experiment (SCQE) is an approach to study the effects of nonrandomized, newly adopted treatments. While covariate adjustment techniques rely on a "no unobserved confounding" assumption, SCQE imposes an assumption on the change in the average nontreatment outcome between successive cohort...

journal_title：Statistics in medicine

authors： Hazlett C,Maokola W,Wulf DA

更新日期：2020-12-10 00:00:00

abstract：:In this article we develop flexible regression models in two respects to evaluate the influence of the covariate variables on the mixed Poisson and continuous responses and to evaluate how the correlation between Poisson response and continuous response changes over time. A scenario for dealing with regression models ...

journal_title：Statistics in medicine

authors： Yang Y,Kang J,Mao K,Zhang J

更新日期：2007-09-10 00:00:00

abstract：:Parameters for latent transition analysis (LTA) are easily estimated by maximum likelihood (ML) or Bayesian method via Markov chain Monte Carlo (MCMC). However, unusual features in the likelihood can cause difficulties in ML and Bayesian inference and estimation, especially with small samples. In this study we explore...

journal_title：Statistics in medicine

authors： Chung H,Lanza ST,Loken E

更新日期：2008-05-20 00:00:00

abstract：:There is an increasing interest in the use of propensity score methods to estimate causal effects in observational studies. However, recent systematic reviews have demonstrated that propensity score methods are inconsistently used and frequently poorly applied in the medical literature. In this study, we compared the ...

journal_title：Statistics in medicine

authors： Austin PC,Mamdani MM

更新日期：2006-06-30 00:00:00

abstract：:In population-based case-control studies, an attempt is made to identify all incident cases diagnosed in a specified population during a fixed time interval. Assuming that this goal is met allows one to obtain measures of risk other than relative risks. In this paper, we describe three approaches to estimate exposure-...

journal_title：Statistics in medicine

authors： Benichou J,Wacholder S

更新日期：1994-03-15 00:00:00

abstract：:Many critical questions in medicine require the analysis of complex multivariate data, often from large data sets describing numerous variables for numerous subjects. In this paper, we describe CoPlot, a tool for visualizing multivariate data in medicine. CoPlot is an adaptation of multidimensional scaling (MDS) that ...

journal_title：Statistics in medicine

authors： Bravata DM,Shojania KG,Olkin I,Raveh A

更新日期：2008-05-30 00:00:00

abstract：:Graphical methods are often used to check goodness-of-fit of models to data. It is common to plot residuals against a reference distribution so that when the model fits the data, the configuration should be close to a straight line. Since the resemblance to a straight line is often unclear, it has been suggested to ad...

journal_title：Statistics in medicine

authors： Cohen A,Barnett O

更新日期：1995-08-30 00:00:00