background & aim: in the survival data with long-term survivors the event has not occurred for all the patients despite long-term follow-up, so the survival time for a certain percent is censored at the  end  of the  study.  mixture  cure  model  was  introduced  by boag,  1949  for  reaching  a  more efficient analysis of this set of data. because of some disadvantages of this model non-mixtur...

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...

conclusions the use of smoothing methods helps us to eliminate non-linear effects but it is more appropriate to use cox proportional hazards model in medical data because of its’ ease of interpretation and capability of modeling both continuous and discrete covariates. also, cox proportional hazards model and smoothing methods analysis identified that age at diagnosis and tumor size were indepe...

background: northern regions of iran have been encountered to dominate malignancies of gastrointestinal (gi) tract. we came to examine the total excess mortality due to the gi cancer in mazandaran province. methods: socio-demographic and clinical data of 484 patients with gi cancer collected during the years 1990-1991were available from babol cancer registry. patients were followed up for 15 ye...

Cox regression model serves as a statistical method for analyzing the survival data, which requires some options such as hazard proportionality. In recent decades, artificial neural network model has been increasingly applied to predict survival data. This research was conducted to compare Cox regression and artificial neural network models in prediction of kidney transplant survival. The prese...

Cox regression model serves as a statistical method for analyzing the survival data, which requires some options such as hazard proportionality. In recent decades, artificial neural network model has been increasingly applied to predict survival data. This research was conducted to compare Cox regression and artificial neural network models in prediction of kidney transplant survival. The prese...

in this research, 6517 records, collected by khojir sheep breeding station (tehran, iran), during 1991 to 2011 were used to estimate genetic parameters of lamb survival in zandi sheep. genetic parameters were estimated using 16 different models of animal model, sire and threshold models using reml procedures. the aic criterion was used to evaluate the models. the effects in the most suitable an...