Performance Evaluation of Distributional Models to Analyze Random Right-Censored Breast Cancer Failure Time Data
Abstract Background Censoring frequently occurs in disease data analysis. Typically, non-parametric and semi-parametric methods are used to deal with different types of censored data. Distributional random right-censored failure time models on breast cancer data are employed to empirically find out a best-fitted model. A large number of studies are available on complete and disease-free survival time, but very few have focused on time to death from breast cancer recurrence.Methods In this retrospective study, we investigated the impact of factors related to breast cancer on cause-specific failure time. We included data from women who suffered from breast cancer as a primary disease and observed recurrence. Several factors related to breast cancer incidence and prognosis are studied. A multivariate accelerated failure time (AFT) model is used to evaluate the combined effect of study factors on death due to breast cancer.Results Univariate Weibull model showed that all factors included in the model have a strong association with breast cancer failure time. These factors are age at diagnosis, age at recurrence, molecular markers (estrogen, progesterone receptors, and Her2.neu), tumor grade, chemotherapy, and radiotherapy. The best model for right-censored breast cancer failure time data was a Weibull AFT, which was chosen by a stepwise backward selection.Conclusions The AFT model is the best choice for the analysis of time to failure data when hazards are non-proportional, as it provides efficient estimates and an estimate of the median failure time ratios.