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arXiv · 2403.12332

A maximum penalised likelihood approach for semiparametric accelerated failure time models with time-varying covariates and partly interval censoring

Aishwarya Bhaskaran·Ding Ma·Benoit Liquet·Angela Hong·Stephane Heritier·Serigne N Lo·Jun Ma
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Abstract

Accelerated failure time (AFT) models are frequently used to model survival data, providing a direct quantification of the relationship between event times and covariates. These models allow for the acceleration or deceleration of failure times through a multiplicative factor that accounts for the effect of covariates. While existing literature provides numerous methods for fitting AFT models with time-fixed covariates, adapting these approaches to scenarios involving both time-varying covariates and partly interval-censored data remains challenging. Motivated by a randomised clinical trial dataset on advanced melanoma patients, we propose a maximum penalised likelihood approach for fitting a semiparametric AFT model to survival data with partly interval-censored failure times. This method also accommodates both time-fixed and time-varying covariates. We utilise Gaussian basis functions to construct a smooth approximation of the non-parametric baseline hazard and fit the model using a constrained optimisation approach. The effectiveness of our method is demonstrated through extensive simulations. Finally, we illustrate the relevance of our approach by applying it to a dataset from a randomised clinical trial involving patients with advanced melanoma.

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Aishwarya Bhaskaran, Ding Ma, Benoit Liquet, Angela Hong, Stephane Heritier, Serigne N Lo, Jun Ma. 2024-03-19. A maximum penalised likelihood approach for semiparametric accelerated failure time models with time-varying covariates and partly interval censoring. https://arxiv.org/abs/2403.12332

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