background and purpose: leukemia is the most prevalent type of cancer in children and its prognostic factors vary in different geographic locations. the aim of this study was to estimate the 5 years survival rate of children suffering from leukemia in kerman, iran and to investigate the factors which might influence it. materials and methods: this was a cohort study conducted on patients with a...

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 patients who ...

BACKGROUND Multivariable models are frequently used in the medical literature, but many clinicians have limited training in these analytic methods. Our objective was to assess the prevalence of multivariable methods in medical literature, quantify reporting of methodological criteria applicable to most methods, and determine if assumptions specific to logistic regression or proportional hazards...

Introduction: Iran experienced a dramatic fertility decline during recent decades. There was also an indication of a shift towards later childbearing from 2000. Past research on fertility has shown that the education variable is the most important determinant of fertility behaviors. However, the impact of education on fertility timing in Iran has been less considered. Methods: In a cross secti...

There are several statistical methods for time-to-event analysis, among which is the Cox proportional hazards model that is most commonly used. However, when the absolute change in risk, instead of the risk ratio, is of primary interest or when the proportional hazard assumption for the Cox proportional hazards model is violated, an additive hazard regression model may be more appropriate. In t...

Early-stage endometrial carcinoma (EC) patients have a high cure rate; however, those with high-risk factors may have poor prognosis. Thus, there is an urgent need for searching for new prognostic molecules to more accurately predict survival of patients. We detected the Rictor mRNA expression level in 30 fresh EC tissue and 17 normal endometrial tissue samples with real-time quantitative RT-PC...

This study involved conducting a survival analysis by fitting Cox proportional hazards model to Korea Labor Panel data analyze the impact of parental job loss on children’s delayed admission colleges and universities in South Korea, using 376 subjects whose education levels were college-level or higher. Since are interval- right-censored, we compared three imputation methods: simple omission, a...

How old are young people when they start having sex? Although this question is important for educators and policymakers, its answer can easily mislead due to methodology that does not take into account age-censoring generational trends. This study investigated whether 1-year birth-year cohorts be jointly modeled by Cox proportional hazards regression estimate sexual debut ages investigate age t...