Survival Analysis of Childbirth Using a Mixture Cure Frailty Model

Azadeh  Naderi; Abbas  Rahimi Foroushani; Ali Moghadas  Jafari; Mohammed I M  Gubari; Mehdi  Yaseri; Mostafa  Hosseini

doi:10.18502/jbe.v11i3.21369

Azadeh Naderi Department of biostatistics and epidemiology, Tehran university of medical sciences, Tehran, Iran.
Abbas Rahimi Foroushani Department of biostatistics and epidemiology, Tehran university of medical sciences, Tehran, Iran.
Ali Moghadas Jafari Farhikhtegan hospital, Azad university of medical sciences, Tehran, Iran.
Mohammed I M Gubari Community medicine, College of medicine, University of Sulaimani, Sulaimani, Iraq.
Mehdi Yaseri Department of biostatistics and epidemiology, Tehran university of medical sciences, Tehran, Iran.
Mostafa Hosseini Department of biostatistics and epidemiology, Tehran university of medical sciences, Tehran, Iran.

DOI: https://doi.org/10.18502/jbe.v11i3.21369

Keywords: Birth; Mixture Cure; Frailty model

Abstract

Introduction: Childbirth plays a crucial role in population growth and maternal health. In recent decades, many nations,including Iran, have experienced declining birth rates. Since childbirth is a recurrent event in a parent's life, it is useful toanalyze it through the lens of recurrent event analysis. This methodological framework, commonly employed in biomedicine,allows for a nuanced examination of the relationship between multiple childbirth experiences and the potential for curedsubjects. This study explores childbirth rates in Hamadan province.

Methods: A total of 633 mothers who gave birth to their first child in 2012 at Fatemiyeh Hospital in Hamadan participatedin this retrospective cohort study. Both mixture cure frailty models and simple frailty models were fitted. The analyses wereconducted using the RSTAN package in RStudio version 26.2.4.

Results: In this study, we analyzed the childbearing patterns of couples and found that the majority (60.6%) had twochildren. Additionally, we discovered that 49% of mothers and 55.9% of fathers had education levels below a diploma.The Kaplan-Meier (KM) curves indicated a cure pattern for families with three or more children, revealing that only10.6% of individuals had three children, and a mere 0.8% had four. Furthermore, results from a mixture cure frailty modeldemonstrated that maternal education plays a crucial role in influencing childbirth probabilities.

Conclusion: Based on the findings of this study, we recommend utilizing mixture cure frailty models rather than simplefrailty models when the dataset contains individuals who are cured.