Frailty model is a survival model designed to account for unobserved heterogeneity in the population. In this paper, we propose a new shared frailty model based on log-logistic as baseline distribution. The Bayesian approach of Markov Chain Monte Carlo (MCMC) technique was employed to estimate the parameters involved in the models. A simulation study was performed to compare the true values and the estimated values of the parameters. Comparison of different proposed models was done by using Bayesian comparison techniques. We apply to real life data set related to kidney infection due to insertion of catheter and the better model is suggested.

Frailty models are intended for use in survival analysis to explain unobserved heterogeneity in an individual caused by various hereditary variables or environmental influences. A shared frailty model was utilized to examine the data. It is based on the idea that frailty affects the hazard rate in a multiplicative manner. In this manuscript, we introduce a new frailty model called the Lindley shared frailty model with exponential power and generalized Rayleigh as baseline distributions. The The Bayesian method of the Monte Carlo method of the Markov chain is used to estimate the parameters used in the model; simulation studies are also carried out to compare the actual and calculated values of the parameters; the proposed model is compared with the Bayesian comparison method Compare and propose the best model of infectious disease data.

Esophageal cancer is one of the main health issues in Mizoram. The risk factors of the disease are related to consumption of alcohol. There have not been any epidemiological studies on this subject in the state. The aim of the study is to assess the relationship between esophageal cancer and consumption of alcohol. Materials and Methods:A hospital based matched case-control study was conducted comprising of 138 cases with histologically confirmed diagnosis of esophageal cancer and 276 controls that were cancer and esophageal cancer disease free. Cases and controls matched by gender and age (± 5 years). Ratio of cases and controls were 1:2. A questionnaire was used to collect information on possible risk factors of esophageal cancer. The odds ratios (OR) and 95% confidence intervals (CI) for gastric cancer were calculated by a conditional logistic regression.Results: Cases had significantly lower education level. Most of the cases are from middle income class. After adjustment for consumption of betel quid, tobacco, smoking, body mass index (BMI), family history of cancer, education level and income level, higher risk of esophageal cancer was found for those who have the habit of consuming alcohol in the morning. After controlling for consumption of betel quid, tobacco, smoking, body mass index (BMI), family history of cancer, education level, income level, dietary habits, physical activity, consumption of Zu(locally brewed alcohol) and both Zu(locally brewed alcohol) and commercial alcohol(rum, whisky, vodka and beer, etc) are also associated with higher risk of esophageal cancer (O.R = 9.820, 95% CI = 2.029-47.523).