Simulation studies play an important role in evaluating the performance of statistical models developed for analyzing complex survival data such as those with competing risks and clustering. This article aims to provide researchers with a basic understanding of competing risks data generation, techniques for inducing cluster-level correlation, and ways to combine them together in simulation studies, in the context of randomized clinical trials with a binary exposure or treatment. We review data generation with competing and semi-competing risks and three approaches of inducing cluster-level correlation for time-to-event data: the frailty model framework, the probability transform, and Moran's algorithm. Using exponentially distributed event times as an example, we discuss how to introduce cluster-level correlation into generating complex survival outcomes, and illustrate multiple ways of combining these methods to simulate clustered, competing and semi-competing risks data with pre-specified correlation values or degree of clustering.
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http://dx.doi.org/10.1177/09622802221136067 | DOI Listing |
Ann Diagn Pathol
January 2025
Latifa Hospital, Dubai, United Arab Emirates.
Isthmoceles are defects related to Caesarean section (CS) scars, known to cause secondary infertility and interfere with in-vitro fertilization in women who have had Caesarean deliveries. The etiologies are multifactorial. Isthmoceles, similar to dehiscent CS scars, can be potential sites for ectopic pregnancies and abnormal placentation.
View Article and Find Full Text PDFJ Biomech
January 2025
Department of Community Medicine and Rehabilitation, Unit of Physiotherapy, Umeå University, Umeå, Sweden. Electronic address:
Anterior cruciate ligament (ACL) reinjury rates among athletes remain very high despite screening protocols designed to assess readiness for return to sport. To better identify biomechanical risk factors for ACL injury, combining neurocognitive challenges and high-impact tasks would more closely resemble sporting demands. We investigated the influence of secondary cognitive tasks on landing mechanics during bilateral drop vertical jumps (DVJs) among athletes following ACL reconstruction and whether sex affected these results.
View Article and Find Full Text PDFBiomater Adv
January 2025
Univ. Lille, CNRS, INRAE, Centrale Lille, UMR 8207 - UMET - Unité Matériaux et Transformations, F-59000 Lille, France. Electronic address:
Abdominal hernia repair is a common surgical procedure, involving in most cases the use of textile meshes providing a mechanical barrier to consolidate the damaged surrounding tissues and prevent the resurgence of the hernia. However, in more than half cases postoperative complications such as adhesions and infections occur at the surface of the mesh, leading to chronic pain for the patient and requiring the removal of the implant. One of the most promising strategies to reduce the risk of postoperative adhesions and infections is to add a physical barrier between the mesh and the abdominal walls.
View Article and Find Full Text PDFFood Chem
December 2024
School of Food Science and Technology, State Key Laboratory of Marine Food Processing & Safety Control, National Engineering Research Center of Seafood, Dalian Polytechnic University, Dalian 116034, China. Electronic address:
Salt enhances flavor and salinity in Chinese curing; however, excessive use can pose health risks, while reducing NaCl may harm taste. This study utilized targeted and untargeted metabolomics to investigate the intrinsic molecular mechanisms that drive flavor formation in cured sea bass subjected to salt. Glycine, succinic acid, lactic acid and uridine significantly contributed to the taste profile of the cured sea bass.
View Article and Find Full Text PDFFood Chem
December 2024
Laboratory of Molecular Nutrition and Immunity, College of Animal Science and Technology, Northeast Agricultural University, Harbin, PR China. Electronic address:
The growing demand for minimally processed foods has heightened the risk of pathogenic contamination. Balancing antimicrobial efficacy with the preservation of probiotic activity remains a significant challenge. In this study, we employed phage display peptide library screening, combined with next-generation sequencing to identify the HIMPIQA domain, which selectively targets pathogenic Escherichia coli (E.
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