A unified estimation procedure is proposed for the analysis of censored data using linear transformation models, which include the proportional hazards model and the proportional odds model as special cases. This procedure is easily implemented numerically and its validity does not rely on the assumption of independence between the covariates and the censoring variable. The estimator is the sam...

PURPOSE Cyclooxygenase-2 (COX-2) plays important roles in the modulation of apoptosis, angiogenesis, immune response, and tumor invasion. Elevated COX-2 expression has been reported to be correlated with reduced survival after radiotherapy. This study examined whether genetic variations in the COX-2 gene are associated with different survival in inoperable locally advanced non-small cell lung c...

In occupational epidemiology, it is often possible to obtain repeated measurements of exposure from a sample of subjects (workers) who belong to exposure groups associated with different levels of exposure. Average exposures from a sample of workers can be assigned to all members of that group including those who are not sampled, leading to a group-based exposure assessment. We discuss how this...

gastric cancer is the most prevalent cancer among men and the third most prevalent cancer among women in iran. its most important reason for death is its belated diagnosis at the advanced stages of the disease. various factors can be effective on the survival of these patients after surgery, which are the major concern in this study.data from 330 patients with gastric cancer who had undergone s...

For survival data regression, the Cox proportional hazards model is the most popular model, but in certain situations the Cox model is inappropriate. Various authors have proposed the proportional odds model as an alternative. Yang and Prentice recently presented a number of easily implemented estimators for the proportional odds model. Here we show how to extend the methods of Yang and Prentic...

We present an asymptotic exponential bound for the deviation of the survival function estimator of the Cox model. We show that the bound holds even when the proportional hazards assumption does not hold.

Line 54: How is the variant associated with mean telomere length? Is it associated with increased/decreased length? The A allele of rs2736100 was associated with decreased telomere length. This is described in the last paragraph of the Background section. Methods Line 144: Should read “Six SNPs” rather than “Six (6) SNPs”. This error has been corrected. State whether the assumptions of the cox ...

Objectives The Cox proportional hazards (PH) model is commonly used in randomised clinical trials (RCTs) to assess a treatment effect after adjusting for known prognostic factors. However, the Cox model requires that a covariate effect is constant over time. Violation of this assumption invalidates the simple Cox model. Various PH checks exist, some in the form of statistical tests and some emp...