Abstract:
Abstract: Breast cancer is the major public health problem throughout the world
and it results in serious physical damages and death. This work proposes the use of
joint model to study breast cancer in patients of Ayder Hospital. The primary
motivation is to contribute to the understanding of the tumor cell progression of
breast cancer, within Ayder Hospital, using a joint model that takes into account
a possible existence of a serial correlation structure within a same subject observations from September 2015 till December 2018. The general aim of this study was
to investigate the risk of longitudinal change in tumor cell level on time to death
due to breast cancer among breast cancer patients. Hospital-based retrospective
cohort study was conducted among breast cancer patients. A joint model of longitudinal and time to death model was used to determine the risk of longitudinal
change in tumor cell level on time to death due to breast cancer patients. These
were used by using JM package in R version. Results from joint models, showed that
the longitudinal Tumor cell progression was signicantly associated with the survival
probability of these patients(estimated association parameter(ɑ) in the joint model
is 0.84 with corresponding (95% CI: 2.28,2.37). A comparison between parameter
estimates obtained in this joint model and independent survival and longitudinal
analysis lead us to conclude that independent analysis brings up bias parameter
