Structured Additive Regression (STAR) Modeling of Women's Age of Menarche and Years of Fertility in Central Portugal

• Activity Number: 422
• Type: Contributed
• Date/Time: Tuesday, August 2, 2011 : 2:00 PM to 3:50 PM
• Sponsor: Section on Statistics in Epidemiology
• Author(s): Bruno C. de Sousa*+ and Elisa Duarte and Carmen Cadarso-Suárez and Vítor Rodrigues and Thomas Kneib
• Companies: Institute of Hygiene and Tropical Medicine and University of Santiago de Compostela and University of Santiago de Compostela and University of Coimbra and Carl von Ossietzky University Oldenburg
• Keywords: Structured Additive Regression (STAR) ; Breast Cancer ; Screening program ; Biostatistics

Abstract

The Portuguese Cancer League (LPCC) is a private non-profit organization dealing with multiple issues related to oncology, including the National Breast Cancer Screening Program. In this study, we analyze approximately 260,000 data records of women that entered the Screening Program for the first time in the central region of Portugal. It is believed that the period of time between the age of menarche and the age of menopause has been increasing over time. Therefore, a new variable called Window was defined as the difference between the age of menopause and the age of menarche, which represents a woman's years of fertility. In this study, the evolution in time and space of the variables Window and the Age of Menarche were analyzed through STAR models, exploring the possible associations with other variables, such as Hormone Replacement Therapy, Pregnancy Status, Nursing Status, and Contraceptive Pills.