Gu and Zheng (1993) established a Bartlett adjustment for the partial likelihood ratio test in the Cox proportional hazards regression model. It is known that the same method of adjustment cannot be used to improve the accuracy of the test statistic derived by Rao’s score method. In this paper, the method of Cordeiro and Ferrari (1991) is used to derive a Bartlett type correction for the score ...

The life cycle cost of a system is influenced by its maintainability. Maintainability is a design parameter, whose operational conditions can affect it significantly. Hence, the effects of these operational conditions should be quantified early in the design phase. The proportional repair model (PRM), which is developed based on the proportional hazard model (PHM), can be used to analyze mainta...

conclusions in this study, sick sinus syndrome and pacemaker mode followed by syncope were independently associated with increased mortality. results survival data were available for 1030 (80%) patients (median age = 71 years [5th to 95th percentile range: 26 - 86 years]) and follow-up was completed for 84.28% of them. according to the results, 56% of the patients had received dual-chamber syst...

Methods: To address this we retrospectively followed 7620 patients who underwent CABG between April 2001 and March 2006. Logistic regression was used to risk adjust in-hospital outcomes. Cox proportional hazards analysis was used to risk adjust Kaplan-Meier freedom from death curves. Outcomes were adjusted for American Heart Association and American College of College of Cardiology recommended ...

RESEARCHDESIGNANDMETHODSdWe examined the 7-year incidence of T2DM in relation to dietary patterns during high school among 37,038 participants in the Nurses’ Health Study II cohort, who completed a food-frequency questionnaire about their diet during high school. Dietary patterns were derived by factor analysis. Cox proportional hazards regression was used to estimate relative risk (RR) and 95%...

The widespread availability of statistical packages has undoubtedly helped hematologists worldwide in the analysis of their data, but has also led to the inappropriate use of statistical methods. In this article, we review some basic concepts of survival analysis and also make recommendations about how and when to perform each particular test using SPSS, Stata and R. In particular, we describe ...

background: the aim of this study is to evaluate the association between different treatments and survival time of breast cancer patients using either standard cox model or stratified cox model. methods: the study was conducted on 15830 women diagnosed with breast cancer in british columbia, canada.  they were divided into eight groups according to patients’ ages and stage of disease either cox...

AMS 2000 subject classifications: 62N02 62G20 Keywords: Kaplan–Meier estimator Martingale Proportional hazards model Proportional odds model Right censoring U-statistic a b s t r a c t Recent advances in the transformation model have made it possible to use this model for analyzing a variety of censored survival data. For inference on the regression parameters, there are semiparametric procedur...