Proportional hazards models are among the most popular regression models in survival analysis. Multi-state models generalize them by jointly considering different types of events and their interrelations, whereas frailty models incorporate random effects to account for unobserved risk factors, possibly shared by clusters of subjects. The integration of multi-state and frailty methodology is an interesting way to control for unobserved heterogeneity in the presence of complex event history structures and is particularly appealing for multicenter clinical trials. We propose the incorporation of correlated frailties in the transition-specific hazard function, thanks to a nested hierarchy. We studied a semiparametric estimation approach based on maximum integrated partial likelihood. We show in a simulation study that the nested frailty multi-state model improves the estimation of the effect of covariates, as well as the coverage probability of their confidence intervals. We present a case study concerning a prostate cancer multicenter clinical trial. The multi-state nature of the model allows us to evidence the effect of treatment on death taking into account intermediate events.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1002/sim.6734 | DOI Listing |
Am J Prev Cardiol
March 2025
School of Population Medicine and Public Health, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China.
Background: Atrial fibrillation (AF) is the most common cardiac arrhythmia around the world with an increased risk of a broad spectrum of adverse comorbidities and death. Whether cardiovascular health (CVH) is associated with AF development remains unclear.
Methods: 238,420 participants without cardiovascular disease at baseline were selected from the UK Biobank study cohort from 2006 to 2010.
Background: Disparities in postoperative nausea and vomiting (PONV) and its prophylaxis may exist based on race, ethnicity, and socioeconomic status (SES). Our objective was to evaluate whether patients from racial and ethnic minority groups and patients from lower SES backgrounds received less appropriate PONV prophylaxis and experienced higher rates of PONV and post-discharge nausea and vomiting (PDNV).
Methods: This retrospective cohort study included 23,333 adults who underwent major surgeries (total knee arthroplasty, cholecystectomy, hysterectomy, and prostatectomy) from 2017-2022 in a single, multi-state hospital system.
J Chem Phys
January 2025
Departamento de Química Física, Facultad de Ciencias Químicas, Universidad Complutense de Madrid, 28040 Madrid, Spain.
Rigid, non-polarizable water models are very efficient from a computational point of view, and some of them have a great ability in predicting experimental properties. There is, however, little room for improvement in simulating water with this strategy, whose main shortcoming is that water molecules do not change their interaction parameters in response to the local molecular landscape. In this work, we propose a novel modeling strategy that involves using two rigid non-polarizable models as states that water molecules can adopt depending on their molecular environment.
View Article and Find Full Text PDFSensors (Basel)
December 2024
Institute of Railway Research, University of Huddersfield, Huddersfield HD1 3DH, UK.
Conventional floating bridge systems used during emergency repairs, such as during wartime or after natural disasters, typically rely on passive rubber bearings or semi-active control systems. These methods often limit traffic speed, stability, and safety under dynamic conditions, including varying vehicle loads and fluctuating water levels. To address these challenges, this study proposes a novel Hydraulic Self-Adaptive Bearing System (HABS).
View Article and Find Full Text PDFAddict Sci Clin Pract
January 2025
Departments of Family and Community Medicine and Health and Clinical Outcomes Research, Saint Louis University School of Medicine, Saint Louis, MO, USA.
Background: The postpartum period provides an opportunity for birthing people with opioid use disorder (OUD) to consider their future reproductive health goals. However, the relationship between the use of medication for opioid use disorder (MOUD) and contraception utilization is not well understood. We used multistate administrative claims data to compare contraception utilization rates among postpartum people with OUD initiating buprenorphine (BUP) versus no medication (psychosocial services receipt without MOUD (PSY)) in the United States (US).
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!