Abstract:
The study dealt with the problem of determining an appropriate survival
model for breast cancer patients data based on the distribution of survival
time, where breast cancer is one of the most common causes of cancer
death.This study aimed to find out the factors affecting on the survival
analysis of breast cancer patients and also identify the effect of the
distribution of survival time on the parametric survival models, also to
determine the appropriate model among the parametric survival models and
non-parametric (Cox model) by using (AIC( and )BIC) criteria. A sample
of 246 patients was taken from Khartoum Oncology Hospital, 150 (61%)
died, Survival times were simulated according to the distributions of the
three studied models (Exponential-Weibull-Gompertz). The hypotheses of
study is there an effect by the factors of the study on the survival time, and
are there any differences between parametric models according to it is
survival time distribution, and between them and Cox model. The results
study found that the factors: education level, marital status, number of
children, stage of disease and treatments (radiation-chemical-hormonalsurgical)
have an effect on survival, While factors: age, function, tumor
side are not an effect on survival time, and distribution of survival time
effects on the appropriate parametric model, the Weibull model is the
appropriate model based on the (AIC and BIC) criteria as it has the lowest
value for both criteria. The study Recommended that to study the effect of
the estimation methods of Cox model on the significance of the estimated
parameters model, also to studying other parametric survival models and
comparing them with each other and with the Cox model, concern to
factors affecting survival and benefit from them in increasing the likelihood
of survival as well as in prevention.
