On the use of the logistic model in prospective studies.

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：:Service on the Data Monitoring Committee of the CPEP (Calcium for Pre-eclampsia Prevention) has led us to four conclusions about clinical trials which we should like to present to this gathering of biostatisticians for their reactions: (i) meta-analyses of the pertinent published trials of the same therapy should alwa...

journal_title：Statistics in medicine

authors： Chalmers TC,Lau J

更新日期：1996-06-30 00:00:00

abstract：:We estimate a Cox proportional hazards model where one of the covariates measures the level of a subject's cognitive functioning by grading the total score obtained by the subject on the items of a questionnaire. A case study is presented where the sample includes partial respondents, who did not answer some questionn...

journal_title：Statistics in medicine

authors： Lagona F,Zhang Z

更新日期：2010-01-30 00:00:00

abstract：:Our objective is to develop a model to estimate the relative risk of disease in each area, Ai, i=1, ... , n, of a region and to identify areas of unusually high or low risk. We use a product partition model (PPM) in which we assume that the true relative risks can be partitioned into a number of components or sets of ...

journal_title：Statistics in medicine

authors： Hegarty A,Barry D

更新日期：2008-08-30 00:00:00

abstract：:In a variety of biomedical applications, particularly those involving screening for infectious diseases, testing individuals (e.g. blood/urine samples, etc.) in pools has become a standard method of data collection. This experimental design, known as group testing (or pooled testing), can provide a large reduction in ...

journal_title：Statistics in medicine

authors： Chen P,Tebbs JM,Bilder CR

更新日期：2009-10-15 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：:Detecting safety signals in clinical trial safety data is known to be challenging due to high dimensionality, rare occurrence, weak signal, and complex dependence. We propose a new hierarchical testing approach for analyzing safety data from a typical randomized clinical trial. This approach accounts for the hierarchi...

journal_title：Statistics in medicine

authors： Tan X,Chen BE,Sun J,Patel T,Ibrahim JG

更新日期：2020-05-15 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：:Multi-type recurrent event data arise when two or more different kinds of events may occur repeatedly over a period of observation. The scientific objectives in such settings are often to describe features of the marginal processes and to study the association between the different types of events. Interval-censored m...

journal_title：Statistics in medicine

authors： Chen BE,Cook RJ,Lawless JF,Zhan M

更新日期：2005-03-15 00:00:00

abstract：:The statistical analysis of spatially correlated data has become an important scientific research topic lately. The analysis of the mortality or morbidity rates observed at different areas may help to decide if people living in certain locations are considered at higher risk than others. Once the statistical model for...

journal_title：Statistics in medicine

authors： Hsiao CK,Tzeng JY,Wang CH

更新日期：2000-07-30 00:00:00

abstract：:In longitudinal studies with incomplete data, where the number of time points can become numerous, it is often advantageous to model the covariance matrix. We describe several covariance models (for example, mixed models, compound symmetry, AR(1)-type models, and combination models) that offer parsimonious alternative...

journal_title：Statistics in medicine

authors： Grady JJ,Helms RW

更新日期：1995-07-15 00:00:00

abstract：:Exposure to a carcinogen is likely to be reflected by temporal clustering of cancer cases among the community members. Detection of such clustering is a complicated task in general and more so in a small workplace community with low turnover rate. In this study we applied the CUSCORE test and the q-interval statistic ...

journal_title：Statistics in medicine

authors： Chen R,Froom P

更新日期：2003-10-15 00:00:00

abstract：:Multiple imputation by chained equations is a flexible and practical approach to handling missing data. We describe the principles of the method and show how to impute categorical and quantitative variables, including skewed variables. We give guidance on how to specify the imputation model and how many imputations ar...

journal_title：Statistics in medicine

authors： White IR,Royston P,Wood AM

更新日期：2011-02-20 00:00:00

abstract：:Multivariate random length data occur when we observe multiple measurements of a quantitative variable and the variable number of these measurements is also an observed outcome for each experimental unit. For example, for a patient with coronary artery disease, we may observe a number of lesions in that patient's coro...

journal_title：Statistics in medicine

authors： Barnhart HX,Kosinski AS,Sampson AR

更新日期：1999-01-30 00:00:00

abstract：:Antimicrobial resistance has become one of the main public health burdens of the last decades, and monitoring the development and spread of non-wild-type isolates has therefore gained increased interest. Monitoring is performed based on the minimum inhibitory concentration (MIC) values, which are collected through the...

journal_title：Statistics in medicine

authors： Jaspers S,Aerts M,Verbeke G,Beloeil PA

更新日期：2014-01-30 00:00:00

abstract：:Pattern-mixture models (PMM) and selection models (SM) are alternative approaches for statistical analysis when faced with incomplete data and a nonignorable missing-data mechanism. Both models make empirically unverifiable assumptions and need additional constraints to identify the parameters. Here, we first introduc...

journal_title：Statistics in medicine

authors： Kaciroti NA,Raghunathan T

更新日期：2014-11-30 00:00:00

abstract：:The semi-Markov assumption emphasizes the importance of time spent in a state. In order to compute this type of multistate model, most transition times are always considered to be exactly identified or right censored. However, in the longitudinal analysis of chronic diseases, investigators are often confronted with in...

journal_title：Statistics in medicine

authors： Foucher Y,Giral M,Soulillou JP,Daures JP

更新日期：2007-12-30 00:00:00

abstract：:Combinatorial drugs have been widely applied in disease treatment, especially chemotherapy for cancer, due to its improved efficacy and reduced toxicity compared with individual drugs. The study of combinatorial drugs requires efficient experimental designs and proper follow-up statistical modeling techniques. Linear ...

journal_title：Statistics in medicine

authors： Xiao Q,Wang L,Xu H

更新日期：2019-01-30 00:00:00

abstract：:Correlation analysis is widely used in biomedical and psychosocial research for assessing rater reliability, precision of diagnosis and accuracy of proxy outcomes. The popularity of longitudinal study designs has propelled the proliferation in recent years of new methods for longitudinal and other multi-level clustere...

journal_title：Statistics in medicine

authors： Tu XM,Feng C,Kowalski J,Tang W,Wang H,Wan C,Ma Y

更新日期：2007-09-30 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：: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：:Girardeau, Ravaud and Donner in 2008 presented a formula for sample size calculations for cluster randomised crossover trials, when the intracluster correlation coefficient, interperiod correlation coefficient and mean cluster size are specified in advance. However, in many randomised trials, the number of clusters is...

journal_title：Statistics in medicine

authors： Kelly TL,Pratt N

更新日期：2019-08-15 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：:In this paper, we discuss family-based association test (FBATs) relating genetic data to survival and time-to-onset data. We show how the standard logrank and Wilcoxon statistics can be used with family data to develop tests of association. We prove that the FBAT-logrank approach can be identical to the proportional h...

journal_title：Statistics in medicine

authors： Lange C,Blacker D,Laird NM

更新日期：2004-01-30 00:00:00

abstract：:In time-to-event analysis, the traditional summary measures have been based on the hazard function, survival function, quantile event time, restricted mean event time, and residual lifetime. Under competing risks, furthermore, typical summary measures have been the cause-specific hazard function and cumulative inciden...

journal_title：Statistics in medicine

authors： Jia Y,Jeong JH

更新日期：2021-01-06 00:00:00

abstract：:Log-linear models for capture-recapture type data are widely used for estimating sizes of populations. Log-linear methods model conditional interactions between the sources. Often, however, the marginal associations are more appropriate and easier for the practitioner to conceptualize. Analyses here of previously publ...

journal_title：Statistics in medicine

authors： Regal RR,Hook EB

更新日期：1998-01-15 00:00:00

abstract：:This paper describes statistical procedures for use in an experiment that compares two handwashing protocols. The evaluation of a handwashing protocol entails collection of the wash effluent. Colony counts for the effluent reflect the number of flora removed by the wash protocol. The analysis aims to formulate and est...

journal_title：Statistics in medicine

authors： Le CT

更新日期：1986-07-01 00:00:00

abstract：:We consider Cox proportional hazards regression when the covariate vector includes error-prone discrete covariates along with error-free covariates, which may be discrete or continuous. The misclassification in the discrete error-prone covariates is allowed to be of any specified form. Building on the work of Nakamura...

journal_title：Statistics in medicine

authors： Zucker DM,Spiegelman D

更新日期：2008-05-20 00:00:00

abstract：:Cost data that arise in the evaluation of health care technologies usually exhibit highly skew, heavy-tailed and, possibly, multi-modal distributions. Distribution-free methods for analysing these data, such as the bootstrap, or those based on the asymptotic normality of sample means, may often lead to inefficient or ...

journal_title：Statistics in medicine

authors： Conigliani C,Tancredi A

更新日期：2005-10-30 00:00:00

abstract：:Sample size planning should reflect the primary objective of a trial. If the primary objective is prediction, the sample size determination should focus on prediction accuracy instead of power. We present formulas for the determination of training set sample size for survival prediction. Sample size is chosen to contr...

journal_title：Statistics in medicine

authors： Götte H,Zwiener I

更新日期：2013-02-28 00:00:00