Abstract Background Gastroesophageal reflux disease (GORD) in patients receiving a lung transplant has been associated with worsened graft function and decreased survival. This analysis aimed to identify whether fundoplication following can improve overall Methods undergoing transplantation between January 1993 2020 were included. Data on oesophageal pH, manometry testing, post-transplant testi...

Confidence intervals (CIs) and the reported predictive ability of statistical models may be misleading if one ignores uncertainty in the model selection procedure. When analyzing time-to-event data using Cox regression, one typically checks the proportional hazards (PH) assumption and subsequently alters the model to address any violations. Such an examination and correction constitute a model ...

The Cox proportional hazards (PH) model usually assumes linearity of the covariates on the log hazard function, which may be violated because linearity cannot always be guaranteed. We propose a partially linear single-index proportional hazards regression model, which can model both linear and nonlinear covariate effects on the log hazard in the proportional hazards model. We adopt a polynomial...