Nonparametric comparison of survival functions is one of the most commonly required task in failure time studies such as clinical trials, and for this, many procedures have been developed under various situations. This paper considers a situation that often occurs in practice but has not been discussed much: the comparison based on interval-censored data in the presence of unequal censoring. That is, one observes only interval-censored data, and the distributions of or the mechanisms behind censoring variables may depend on treatments and thus be different for the subjects in different treatment groups. For the problem, a test procedure is developed that takes into account the difference between the distributions of the censoring variables, and the asymptotic normality of the test statistics is given. For the assessment of the performance of the procedure, a simulation study is conducted and suggests that it works well for practical situations. An illustrative example is provided. Copyright © 2017 John Wiley & Sons, Ltd.
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BMC Palliat Care
January 2025
Caring Futures Institute, Flinders University, Sturt Rd, Bedford Park, Adelaide, South Australia, 5042, Australia.
Background: Clinicians are frequently asked 'how long' questions at end-of-life by patients and those important to them, yet predicting timeframes to death remains uncertain, even in the last weeks and days of life. Patients and families wish to know so they can ask questions, plan, make decisions, have time to visit and say their goodbyes, and have holistic care needs met. Consequently, this necessitates a more accurate assessment of empirical data to better inform prognostication and reduce uncertainty around time until death.
View Article and Find Full Text PDFActa Obstet Gynecol Scand
January 2025
Department of Clinical Medicine, Aarhus University, Aarhus, Denmark.
Introduction: Diagnostic work-up of older women with a positive cervical cancer screening test is often challenging due to incomplete visualization of the transformation zone. To reduce the risk of missing disease, a diagnostic cervical excision may be performed. However, little is known on treatment efficacy and post-treatment surveillance for older women.
View Article and Find Full Text PDFNan Fang Yi Ke Da Xue Xue Bao
December 2024
School of Mathematics and Statistics, Changchun University of Technology, Changchun 130000, China.
: To assess the validity and effectiveness of parameter estimation using a time-dependent Weibull proportional hazards model for survival analysis containing partly interval censored data and explore the impact of different covariates on the results of analysis. : We established a time-dependent Weibull proportional hazards model using the Weibull distribution as the baseline hazard function of the model which incorporated time-varying covariates. Maximum likelihood estimation was employed to estimate the model parameters, which were obtained by optimization of the likelihood function.
View Article and Find Full Text PDFChildren (Basel)
November 2024
Department of Epidemiology & Health Promotion, New York University, New York, NY 10010, USA.
Background/objectives: School-based caries prevention can increase access to critical dental services and reduce oral health inequities. However, little is known regarding the incidence of dental caries in children participating in school caries prevention, and caries diagnosis is often interval censored.
Methods: In this paper, we used data from a longitudinal, school-based, randomized clinical trial of minimally invasive treatments for dental caries to estimate the per-visit incidence rate and compare the hazard of dental caries in children receiving either silver diamine fluoride or glass ionomer dental sealants.
Infection
November 2024
Institute for Medical Epidemiology, Biometry and Informatics (IMEBI), Interdisciplinary Centre for Health Sciences, Medical Faculty of the Martin Luther University Halle-Wittenberg, Halle (Saale), Germany.
Purpose: Post-COVID-19 condition (PCC) poses a substantial burden to affected individuals, health care systems, and society as a whole. We examined factors associated with recovery from PCC, focusing on the vaccination status prior to infection and the virus variant.
Methods: Our analyses are based on the population-based cohort study for digital health research in Germany (DigiHero).
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