A semi-Markov model for multistate and interval-censored data with multiple terminal events. Application in renal transplantation.

abstract：:The generalized estimating equations (GEE) approach is commonly used to model incomplete longitudinal binary data. When drop-outs are missing at random through dependence on observed responses (MAR), GEE may give biased parameter estimates in the model for the marginal means. A weighted estimating equations approach g...

journal_title：Statistics in medicine

authors： Preisser JS,Lohman KK,Rathouz PJ

更新日期：2002-10-30 00:00:00

abstract：:We use a mixed Poisson regression model with extra variation to analyse mortality data cross-classified by age and geographic region. We use estimates of dispersion parameter and fixed effects parameters, obtained by maximizing a marginal quasi-likelihood function, to estimate mortality rates in an empirical Bayes man...

journal_title：Statistics in medicine

authors： Lu WS,Tsutakawa RK

更新日期：1996-07-15 00:00:00

abstract：:Assay sensitivity has been proposed as a criterion for including psychiatric clinical outcome studies in meta-analyses. The authors assess the performance of assay sensitivity as a method for determining study appropriateness for meta-analysis by calculating expected standard drug vs placebo effect sizes for various c...

journal_title：Statistics in medicine

authors： Gelfand LA,Strunk DR,Tu XM,Noble RE,Derubeis RJ

更新日期：2006-03-30 00:00:00

abstract：:Clinical trials often assess therapeutic benefit on the basis of an event such as death or the diagnosis of disease. Usually, there are several additional longitudinal measures of clinical status which are collected to be used in the treatment comparison. This paper proposes a simple non-parametric test which combines...

journal_title：Statistics in medicine

authors： Finkelstein DM,Schoenfeld DA

更新日期：1999-06-15 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 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：:Risk prediction procedures can be quite useful for the patient's treatment selection, prevention strategy, or disease management in evidence-based medicine. Often, potentially important new predictors are available in addition to the conventional markers. The question is how to quantify the improvement from the new ma...

journal_title：Statistics in medicine

authors： Uno H,Tian L,Cai T,Kohane IS,Wei LJ

更新日期：2013-06-30 00:00:00

abstract：:Variation in heart disease (HD) mortality rates across census tracts is greater than expected given binomial error and available explanatory variables. We extended an extra-binomial variation model for rates standardized by the direct method. The overdispersion parameter accounted for 36 per cent of the observed varia...

journal_title：Statistics in medicine

authors： Jarjoura D,Logue E

更新日期：1990-10-01 00:00:00

abstract：:New combination regimens evaluated in phase II cancer clinical trials often show promising results compared to the standard therapy for a disease system. Selection of patients with a better prognosis can be a prominent factor for this optimism. For most disease systems, prognostic variables that are related to the out...

journal_title：Statistics in medicine

authors： Mazumdar M,Fazzari M,Panageas KS

更新日期：2001-03-30 00:00:00

abstract：:Meta-analyses of clinical trials are increasingly seeking to go beyond estimating the effect of a treatment and may also aim to investigate the effect of other covariates and how they alter treatment effectiveness. This requires the estimation of treatment-covariate interactions. Meta-regression can be used to estimat...

journal_title：Statistics in medicine

authors： Simmonds MC,Higgins JP

更新日期：2007-07-10 00:00:00

abstract：:Rationalization of antibiotic therapy in the management of infectious diseases is helped by a knowledge of the patterns of sensitivity and resistance of bacteria to antibiotics and their possible changes both in time and from one hospital unit to another. In this paper we present the results regarding the sensitivitie...

journal_title：Statistics in medicine

authors： Bonetto C,Giannerini S,Giovagnoli A

更新日期：2006-10-30 00:00:00

abstract：:Phase II and phase III trials play a crucial role in drug development programs. They are costly and time consuming and, because of high failure rates in late development stages, at the same time risky investments. Commonly, sample size calculation of phase III is based on the treatment effect observed in phase II. The...

journal_title：Statistics in medicine

authors： Kirchner M,Kieser M,Götte H,Schüler A

更新日期：2016-01-30 00:00:00

abstract：:In conventional survival analysis there is an underlying assumption that all study subjects are susceptible to the event. In general, this assumption does not adequately hold when investigating the time to an event other than death. Owing to genetic and/or environmental etiology, study subjects may not be susceptible ...

journal_title：Statistics in medicine

authors： Chen CH,Tsay YC,Wu YC,Horng CF

更新日期：2013-10-30 00:00:00

abstract：:Clinical prediction models (CPMs) can inform decision making about treatment initiation, which requires predicted risks assuming no treatment is given. However, this is challenging since CPMs are usually derived using data sets where patients received treatment, often initiated postbaseline as "treatment drop-ins." Th...

journal_title：Statistics in medicine

authors： Sperrin M,Martin GP,Pate A,Van Staa T,Peek N,Buchan I

更新日期：2018-12-10 00:00:00

abstract：:The present study investigates the performance of several statistical tests to detect publication bias in diagnostic meta-analysis by means of simulation. While bivariate models should be used to pool data from primary studies in diagnostic meta-analysis, univariate measures of diagnostic accuracy are preferable for t...

journal_title：Statistics in medicine

authors： Bürkner PC,Doebler P

更新日期：2014-08-15 00:00:00

abstract：:The use of logistic models for independent binary data has relied first on asymptotic theory and later on exact distributions for small samples. However, the use of logistic models for dependent analysis based on exact analysis is not as common. Moreover, attention is usually given to one-stage clustering. In this pap...

journal_title：Statistics in medicine

authors： Troxler S,Lalonde T,Wilson JR

更新日期：2011-04-15 00:00:00

abstract：:Many randomized clinical trials include a data and safety monitoring board (DSMB) that is responsible for reviewing accruing data, monitoring performance of the trial, assuring safety of the participants in the trial, and assessing the efficacy of treatment. The DSMB often makes recommendations about continuation of t...

journal_title：Statistics in medicine

authors： Wittes J

更新日期：1993-03-01 00:00:00

abstract：:The Wilcoxon-Mann-Whitney (WMW) test is often used to compare the means or medians of two independent, possibly nonnormal distributions. For this problem, the true significance level of the large sample approximate version of the WMW test is known to be sensitive to differences in the shapes of the distributions. Base...

journal_title：Statistics in medicine

authors： Fagerland MW,Sandvik L

更新日期：2009-05-01 00:00:00

abstract：:Non-linear mixed-effects models (NLMEMs) are used to improve information gathering from longitudinal studies and are applied to treatment evaluation in disease-evolution studies, such as human immunodeficiency virus (HIV) infection. The estimation of parameters and the statistical tests are critical issues in NLMEMs s...

journal_title：Statistics in medicine

authors： Samson A,Lavielle M,Mentré F

更新日期：2007-11-30 00:00:00

abstract：:Cross-sectional designs are often used to monitor the proportion of infections and other post-surgical complications acquired in hospitals. However, conventional methods for estimating incidence proportions when applied to cross-sectional data may provide estimators that are highly biased, as cross-sectional designs t...

journal_title：Statistics in medicine

authors： Fluss R,Mandel M,Freedman LS,Weiss IS,Zohar AE,Haklai Z,Gordon ES,Simchen E

更新日期：2013-06-30 00:00:00

abstract：:We discuss some of the fundamental concepts underlying the development of frailty and random effects models in survival. One of these fundamental concepts was the idea of a frailty model where each subject has his or her own disposition to failure, their so-called frailty, additional to any effects we wish to quantify...

journal_title：Statistics in medicine

authors： O'Quigley J,Stare J

更新日期：2002-11-15 00:00:00

abstract：:For patients who were previously treated for prostate cancer, salvage hormone therapy is frequently given when the longitudinal marker prostate-specific antigen begins to rise during follow-up. Because the treatment is given by indication, estimating the effect of the hormone therapy is challenging. In a previous pape...

journal_title：Statistics in medicine

authors： Taylor JM,Shen J,Kennedy EH,Wang L,Schaubel DE

更新日期：2014-01-30 00:00:00

abstract：:This paper considers the regression analysis of CD4 cell counts, a commonly used indicator and prognostic factor of AIDS progression. For this purpose, a number of methods have been proposed and most of them are based on random effects models. We present an alternative that is based on a mean function regression model...

journal_title：Statistics in medicine

authors： Sun J

更新日期：2001-11-15 00:00:00

abstract：:It has been increasingly common to analyze simultaneously repeated measures and time to failure data. In this paper we propose a joint model when the repeated measures are semi-continuous, characterized by the presence of a large portion of zero values, as well as right skewness of non zero (positive) values. Examples...

journal_title：Statistics in medicine

authors： Liu L

更新日期：2009-03-15 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：:This article introduces a global hypothesis test intended for studies with multiple endpoints. Our test makes use of a priori predictions about the direction of the result of each endpoint and we weight these predictions using the sample correlation matrix. The global alternative hypothesis concerns a parameter, ...

journal_title：Statistics in medicine

authors： Montgomery RN,Mahnken JD

更新日期：2020-12-10 00:00:00

abstract：:Kappa coefficients are measures of correlation between categorical variables often used as reliability or validity coefficients. We recapitulate development and definitions of the K (categories) by M (ratings) kappas (K x M), discuss what they are well- or ill-designed to do, and summarize where kappas now stand with ...

journal_title：Statistics in medicine

authors： Chmura Kraemer H,Periyakoil VS,Noda A

更新日期：2002-07-30 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：:It is valuable in many studies to assess both intrarater and interrater agreement. Most measures of intrarater agreement do not adjust for unequal estimates of prevalence between the separate rating occasions for a given rater and measures of interrater agreement typically ignore data from the second set of assessment...

journal_title：Statistics in medicine

authors： Lester Kirchner H,Lemke JH

更新日期：2002-06-30 00:00:00

abstract：:We consider counting process methods for analysing time-to-event data with multiple or recurrent outcomes, using the models developed by Anderson and Gill, Wei, Lin and Weissfeld and Prentice, Williams and Peterson. We compare the methods, and show how to implement them using popular statistical software programs. By ...

journal_title：Statistics in medicine

authors： Therneau TM,Hamilton SA

更新日期：1997-09-30 00:00:00