The probability of a cancer cluster due to chance alone.

abstract：:Multilevel mixed effects survival models are used in the analysis of clustered survival data, such as repeated events, multicenter clinical trials, and individual participant data (IPD) meta-analyses, to investigate heterogeneity in baseline risk and covariate effects. In this paper, we extend parametric frailty model...

journal_title：Statistics in medicine

authors： Crowther MJ,Look MP,Riley RD

更新日期：2014-09-28 00:00:00

abstract：:There is a single-minded focus on events in survival analysis, and we often ignore longitudinal data that are collected together with the event data. This is due to a lack of methodology but also a result of the artificial distinction between survival and longitudinal data analyses. Understanding the dynamics of such ...

journal_title：Statistics in medicine

authors： Aalen OO

更新日期：2012-08-15 00:00:00

abstract：:Conditional power and predictive power provide estimates of the probability of success at the end of the trial based on the information from the interim analysis. The observed value of the time to event endpoint at the interim analysis could be biased for the true treatment effect due to early censoring, leading to a ...

journal_title：Statistics in medicine

authors： Sun L,Wan Y

更新日期：2018-08-15 00:00:00

abstract：:Clinical trials often assess efficacy by comparing treatments on the basis of two or more event-time outcomes. In the case of cancer clinical trials, progression-free survival (PFS), which is the minimum of the time from randomization to progression or to death, summarizes the comparison of treatments on the hazards f...

journal_title：Statistics in medicine

authors： Finkelstein DM,Schoenfeld DA

更新日期：2014-05-30 00:00:00

abstract：:Correlated data are obtained in longitudinal epidemiological studies, where repeated measurements are taken on individuals or groups over time. Such longitudinal data are ideally analyzed using multilevel modeling approaches, which appropriately account for the correlations in repeated responses in the same individual...

journal_title：Statistics in medicine

authors： Xanthakis V,Sullivan LM,Vasan RS

更新日期：2013-12-10 00:00:00

abstract：:In this paper, an approach to estimating the cumulative mean function for history process with time dependent covariates and right censored time-to-event variable is developed using the combined technique of joint modeling and inverse probability weighting method. The consistency of proposed estimator is derived. Theo...

journal_title：Statistics in medicine

authors： Deng D

更新日期：2016-11-10 00:00:00

abstract：:Medical costs data with administratively censored observations often arise in cost-effectiveness studies of treatments for life-threatening diseases. Mean of medical costs incurred from the start of a treatment until death or a certain time point after the implementation of treatment is frequently of interest. In many...

journal_title：Statistics in medicine

authors： Jiang H,Zhou XH

更新日期：2004-11-15 00:00:00

abstract：:In natural history studies of chronic disease, it is of interest to understand the evolution of key variables that measure aspects of disease progression. This is particularly true for immunological variables among persons infected with the human immunodeficiency virus (HIV). The natural time scale for such studies is...

journal_title：Statistics in medicine

authors： Vittinghoff E,Malani HM,Jewell NP

更新日期：1994-06-15 00:00:00

abstract：:Writing the variance of the Mantel-Haenszel estimator under the null of homogeneity and inverting the corresponding test, we arrive at an improved confidence interval for the common risk difference in stratified 2 × 2 tables. This interval outperforms a variety of other intervals currently recommended in the literatur...

journal_title：Statistics in medicine

authors： Klingenberg B

更新日期：2014-07-30 00:00:00

abstract：:The sojourn time, time spent in the preclinical detectable phase (PCDP) for chronic diseases, for example, breast cancer, plays an important role in the design and assessment of screening programmes. Traditional methods to estimate it usually assume a uniform incidence rate of preclinical disease from a randomized con...

journal_title：Statistics in medicine

authors： Duffy SW,Chen HH,Tabar L,Day NE

更新日期：1995-07-30 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：:In drug-drug interaction (DDI) research, a two drug interaction is usually predicted by individual drug pharmacokinetics (PK). Although subject-specific drug concentration data from clinical PK studies on inhibitor/inducer or substrate's PK are not usually published, sample mean plasma drug concentrations and their st...

journal_title：Statistics in medicine

authors： Li L,Yu M,Chin R,Lucksiri A,Flockhart DA,Hall SD

更新日期：2007-09-10 00:00:00

abstract：:Recent studies have indicated variation in the infectivity beta of HIV among heterosexual couples. We represent this heterogeneity by modelling beta as a random variable. Using data on the number of contacts and seroconversion of couples, we fit the model by maximum-likelihood estimation with a beta distribution and a...

journal_title：Statistics in medicine

authors： Wiley JA,Herschkorn SJ,Padian NS

更新日期：1989-01-01 00:00:00

abstract：:This paper develops methods of analysis for active extension clinical trials. Under this design, patients are randomized to treatment or placebo for a period of time (period 1), and then all patients receive treatment for an additional period of time (period 2). We assume a continuous outcome is measured at baseline a...

journal_title：Statistics in medicine

authors： Hu Z,Follmann D

更新日期：2007-05-30 00:00:00

abstract：:Sam Greenhouse joined the Census Bureau as a clerk at an interesting time period for the agency. The first use of sampling in the decennial census occurred in 1940. There was a major expansion of the amount of data collected. The organization of the Census Bureau underwent radical changes, including the growth of the ...

journal_title：Statistics in medicine

authors： Keller J,Clark CZ

更新日期：2003-11-15 00:00:00

abstract：:In repeated measures settings, modeling the correlation pattern of the data can be immensely important for proper analyses. Accurate inference requires proper choice of the correlation model. Optimal efficiency of the estimation procedure demands a parsimonious parameterization of the correlation structure, with suffi...

journal_title：Statistics in medicine

authors： Simpson SL,Edwards LJ,Muller KE,Sen PK,Styner MA

更新日期：2010-07-30 00:00:00

abstract：:Multi-state models are useful for modelling disease progression where the state space of the process is used to represent the discrete disease status of subjects. Often, the disease process is only observed at clinical visits, and the schedule of these visits can depend on the disease status of patients. In such situa...

journal_title：Statistics in medicine

authors： Lesperance ML,Sabelnykova V,Nathoo FS,Lau F,Downing MG

更新日期：2015-12-20 00:00:00

abstract：:A method is proposed to infer the randomized treatment effect on survival after an adjustment for a post-randomization variable. The post-randomization variable is made independent of the treatment assignment and is considered a surrogate for baseline prognostic factors. The relationship between the post-randomization...

journal_title：Statistics in medicine

authors： Heller G

更新日期：2001-11-30 00:00:00

abstract：:Phase II studies in oncology are frequently conducted as two-stage single-arm trials with a binary endpoint indicating tumor response. As a common feature of these designs, the sample sizes of the two stages and the decision rules for the interim and the final analysis have to be pre-specified and adhered to strictly ...

journal_title：Statistics in medicine

authors： Englert S,Kieser M

更新日期：2015-06-15 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 goal of screening programmes for cancer is early detection and treatment with a consequent reduction in mortality from the disease. Screening programmes need to assess the true benefit of screening, that is, the length of time of extension of survival beyond the time of advancement of diagnosis (lead-time). This p...

journal_title：Statistics in medicine

authors： Xu JL,Prorok PC

更新日期：1995-12-30 00:00:00

abstract：:Many split-mouth trials are characterized by the pairing of site-specific outcome and baseline data within each segment of a subject's mouth. However when the response variable of interest is binary, methods of statistical analysis for this design are not well developed. In this paper we present several analytic appro...

journal_title：Statistics in medicine

authors： Donner A,Zou GY

更新日期：2007-08-15 00:00:00

abstract：:This paper considers the analysis of longitudinal data complicated by the fact that during follow-up patients can be in different disease states, such as remission, relapse or death. If both the response of interest (for example, quality of life (QOL)) and the amount of missing data depend on this disease state, ignor...

journal_title：Statistics in medicine

authors： le Cessie S,de Vries EG,Buijs C,Post WJ

更新日期：2009-12-30 00:00:00

abstract：:The effective dose (ED) is the pharmaceutical dosage required to produce a therapeutic response in a fixed proportion of the patients. When only one drug is considered, the problem is a univariate one and has been well-studied. However, in the multidimensional setting, that is, in the presence of combinations of agent...

journal_title：Statistics in medicine

authors： Jankowski H,Ji X,Stanberry L

更新日期：2014-10-30 00:00:00

abstract：:Biomarkers, increasingly used in biomedical studies for the diagnosis and prognosis of acute and chronic diseases, provide insight into the effectiveness of treatments and potential pathways that can be used to guide future treatment targets. The measurement of these markers is often limited by the sensitivity of the ...

journal_title：Statistics in medicine

authors： Lee M,Kong L,Weissfeld L

更新日期：2012-07-30 00:00:00

abstract：:Correlation is inherent in longitudinal studies due to the repeated measurements on subjects, as well as due to time-dependent covariates in the study. In the National Longitudinal Study of Adolescent to Adult Health (Add Health), data were repeatedly collected on children in grades 7-12 across four waves. Thus, obser...

journal_title：Statistics in medicine

authors： Irimata KM,Broatch J,Wilson JR

更新日期：2019-05-30 00:00:00

abstract：:Tumour registry linkage, chart review and patient self-report are all commonly used ascertainment methods in cancer epidemiology. These methods are used for estimating the incidence or prevalence of different cancer types in a population, and for investigating the effects of possible risk factors for cancer. Tumour re...

journal_title：Statistics in medicine

authors： Bernatsky S,Joseph L,Bélisle P,Boivin JF,Rajan R,Moore A,Clarke A

更新日期：2005-08-15 00:00:00

abstract：:Thomas et al. presented the application of empirical-Bayes methods to the problem of multiple inference in epidemiologic studies. One limitation of their approach, which they noted, was the need to assume exchangeable log relative-risk parameters, and independent relative-risk estimates. Numerical integration was also...

journal_title：Statistics in medicine

authors： Greenland S

更新日期：1992-01-30 00:00:00

abstract：:The treatment effect sizes that can be detected with sufficient power up to the different interim analyses constitute a clinically meaningful criterion for the selection of a group sequential test for a clinical trial. For any pre-specified sequence of effect sizes, it is possible to construct group sequential boundar...

journal_title：Statistics in medicine

authors： Schäfer H,Müller HH

更新日期：2004-05-15 00:00:00

abstract：:In studies with survival or time-to-event outcomes, a competing risk is an event whose occurrence precludes the occurrence of the primary event of interest. Specialized statistical methods must be used to analyze survival data in the presence of competing risks. We conducted a review of randomized controlled trials wi...

journal_title：Statistics in medicine

authors： Austin PC,Fine JP

更新日期：2017-04-15 00:00:00