background & aim: we aimed to describe a standard survival analysis, so that we can analyze some factors related to the time of occurrence of different types of reflux (unilateral-left, unilateralright, and bilateral) in children with antenatal hydronephrosis (anh) and to provide an approach taking competing risks into account. methods & materials: we used data of 193 children that was collecte...

The Survival Kit is a Fortran 90 Software intended for survival analysis using proportional hazards models and their extension to frailty models with a single response time. The hazard function is described as the product of a baseline hazard function and a positive (exponential) function of possibly time-dependent fixed and random covariates. Stratified Cox, grouped data and Weibull models can...

BACKGROUND In clinical trials, cyclooxygenase (COX)-2-selective nonsteroidal anti-inflammatory drugs (NSAIDs) were associated with an increased risk of thromboembolic events. We studied the association between NSAID use and risk of stroke in the prospective, population-based Rotterdam Study. METHODS We followed 7636 persons free of stroke at baseline (1991-1993) for incident stroke until Sept...

Background: The incidence of restenosis in patients suffering from coronary artery disease after undergoing angioplasty is of paramount importance. Accordingly, this study aimed to investigate factors affecting the time of the first incidence of restenosis in patients undergone angioplasty in the city of Zanjan, Iran.   Methods: This retrospective cohort study was conducted on 421 patie...

Background & Aims: Renal transplantation is the best therapeutic option for End Stage Renal Disease (ESRD). The aim of this study was to determine the graft survival rate of renal transplantation in patients who have been transplanted from live donor in Shiraz Transplant Research Center, Shiraz, Iran. Methods: In a survival analysis study, organ survival rate after kidney transplantation from...

This study was designed to investigate causes of culling in industrial dairy herds in Fars province and to describe the pattern of reason-specific culling with respect to age of animal and interval from calving to culling. A total number of 9 dairy herds were selected for the study and information about culling reasons, birth date, last calving date and culling date was collected for culled cow...

In clinical studies of time-to-event data, a quantity interest to the clinician is their patient's risk an event. However, methods relying on time matching or risk-set sampling (including Cox regression) eliminate baseline hazard from estimating function. As consequence, focus has been reporting ratios instead survival cumulative incidence curves. Indeed, patient requires separate estimation ha...

background: kidney transplantation is the best alternative treatment for end-stage renal disease. several studies have been devoted to investigate predisposing factors of graft rejection. however, there is inconsistency between the results. the objective of the present study was to utilize an intuitive and robust approach for variable selection, random survival forests (rsf), and to identify im...