Survival analysis of patients with colorectal cancer with the Inverse Entezar Weibull model

objective: In Iran, colorectal cancer is the third most common cancer in women and the fifth most common cancer in men. Weibull distribution has been one of the most common parametric models in survival time analysis. we carried out the Inverse Entezar Weibull model that has various hazard functions, single-mode, one-shape and two-mode. This descriptive-analytical study was performed on patients with colorectal cancer registered in the gastrointestinal center of Taleghani Hospital with at least ۵ years of follow-up in the presence of an independent variables and with censored data. The data file contains gender, age, body mass index, location of tumor spread and time of death. the total number of patient who collaborated was ۲۳۵ people. After fitting the IENW model, the significance of the mentioned independent variables was evaluated by the maximum likelihood method using R and SAS software.Results: As can be seen in Table ۱, the IENW distribution sequence statistic has a lower Akaike Information Criterion and therefore a better fit to the data, according to AIC.Conclusion: This study showed that Invrse Entezar Weibull distribution aids in having more appropriate fitting than common distribution in assessing the survival of colorectal cancer patients.

Keywords:

colorectal cancer , survival Aanalysis , censored data , Weibull distribution , maximum likelihood method , sequence statistic , Akaike Information Criterion