title: Survival of patients with stomach adenocarcinoma in North of Iran.
abstract: OBJECTIVE
  This study was proposed for estimation of survival time in patients with stomach adenocarcinoma.
  
  
  BACKGROUND
  North of Iran has a high mortality rate of stomach adenocarcinoma.
  
  
  METHODS
  The study was historical cohort. The samples were the patients with stomach adenocarcinoma referred to Tooba Clinic between three years (2007-2010). Survival estimates were calculated using the Kaplan-Meier method the effects of covariates on survival time were assessed by, using survival parametric regression model with gamma frailty.
  
  
  RESULTS
  The survival probability of more than two years of patients was calculated 27.7% by using Kaplan Mayer method. The stage, metastasis, surgery, and age were the variables which affect the survival probability of patients, by using survival parametric regression model with gamma frailty and hazard ratio of patients with three treatment protocol was 0.43 times of others (P<0.01) and increasing of patients ages decrease life time of them significantly as per year increasing patient age, risk of death increased by 4% (P<0.04) and patients with staging disease lower 4 had hazard ratio lower than 0.46 times of stage 4 (P<0.01).
  
  
  CONCLUSIONS
  The survival time of our patients is much lower than the developed countries, which are related to latency in diagnosis and therapeutic limitations.
authors.affiliation: Department of Biostatistics, Faculty of Health, Health Sciences Research Center, Mazandaran University of Medical Sciences, Sari, Iran.
authors.forename: Jamshid
authors.initials: J
authors.lastname: Yazdani-Charati
authors.affiliation: Department of Internal Medicine, Faculty of Medicine, Mazandaran University of Medical Sciences, Sari, Iran.
authors.forename: Ghasem
authors.initials: G
authors.lastname: Janbabaei
authors.affiliation: Department of Occupational Health, Faculty of Health, Health Sciences Research Center, Mazandaran University of Medical Sciences, Sari, Iran.
authors.forename: Siavosh
authors.initials: S
authors.lastname: Etemadinejad
authors.affiliation: Department of Biostatistics, Faculty of Health, Mazandaran University of Medical Sciences, Sari, Iran.
authors.forename: Samaneh
authors.initials: S
authors.lastname: Sadeghi
authors.affiliation: Department of Mathematics, Statistics and Computer Sciences, Tehran University, Tehran, Iran.
authors.forename: Firoozeh
authors.initials: F
authors.lastname: Haghighi
keywords: Cox hazard proportional model; Life table; Parametric model; Stomach adenocarcinoma