The new Neyman type A generalized odd log-logistic-G-family with cure fraction

J Appl Stat. 2021 May 3;49(11):2805-2824. doi: 10.1080/02664763.2021.1922994. eCollection 2022.

Abstract

The work proposes a new family of survival models called the Odd log-logistic generalized Neyman type A long-term. We consider different activation schemes in which the number of factors M has the Neyman type A distribution and the time of occurrence of an event follows the odd log-logistic generalized family. The parameters are estimated by the classical and Bayesian methods. We investigate the mean estimates, biases, and root mean square errors in different activation schemes using Monte Carlo simulations. The residual analysis via the frequentist approach is used to verify the model assumptions. We illustrate the applicability of the proposed model for patients with gastric adenocarcinoma. The choice of the adenocarcinoma data is because the disease is responsible for most cases of stomach tumors. The estimated cured proportion of patients under chemoradiotherapy is higher compared to patients undergoing only surgery. The estimated hazard function for the chemoradiotherapy level tends to decrease when the time increases. More information about the data is addressed in the application section.

Keywords: 62Nxx; Long-term survivors; Neyman type A distribution; odd log-logistic-g-family; sensitivity analysis.