Abstract:
:We consider bivariate survival times for heterogeneous populations, where heterogeneity induces deviations in an individual's risk of an event as well as associations between survival times. The heterogeneity is characterized by a bivariate frailty model. We measure the heterogeneity effects through deviations associated with hazard functions and an association function defined through the conditional hazard functions: the cross-ratio function proposed by Oakes. We show how the deviation and association measures are determined by the frailty distribution. A Gibbs sampling method is developed for Bayesian inferences on regression coefficients, frailty parameters and the heterogeneity measures. The method is applied to a mental health care data set.
journal_name
Stat Medjournal_title
Statistics in medicineauthors
Xue X,Ding Ydoi
10.1002/(sici)1097-0258(19990430)18:8<907::aid-simsubject
Has Abstractpub_date
1999-04-30 00:00:00pages
907-18issue
8eissn
0277-6715issn
1097-0258pii
10.1002/(SICI)1097-0258(19990430)18:8<907::AID-SIMjournal_volume
18pub_type
杂志文章abstract::Lower urinary tract symptoms can indicate the presence of urinary tract infection (UTI), a condition that if it becomes chronic requires expensive and time consuming care as well as leading to reduced quality of life. Detecting the presence and gravity of an infection from the earliest symptoms is then highly valuable...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.6786
更新日期:2016-04-15 00:00:00
abstract::Age-period-cohort (APC) analysis is widely used in cancer epidemiology to model trends in cancer rates. We develop methods for comparative APC analysis of two independent cause-specific hazard rates assuming that an APC model holds for each one. We construct linear hypothesis tests to determine whether the two hazards...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.3865
更新日期:2010-05-20 00:00:00
abstract::Interpretation of the Mantoux test for tuberculous infection can be complicated by cross-reactions caused by infection with non-specific mycobacteria. Thus, the distribution of positive indurations is a mixture of two distributions. To estimate tuberculous infection prevalence, the marginal distribution of indurations...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.745
更新日期:2001-04-15 00:00:00
abstract::We present a method to determine the number of subjects, k, and number of repeated measurements, n, that minimize the overall cost of conducting a reliability study, while providing acceptable power for tests of hypotheses concerning the reliability coefficient rho. Tables showing optimal choices of k and n under vari...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4780060602
更新日期:1987-09-01 00:00:00
abstract::Effective statistical help to biological and medical research demands thorough involvement of the statistician. The breadth of his activities can be illustrated by considering the questions he needs to discuss with his scientific colleagues in the course of planning a comparative experiment. The paper presents and com...
journal_title:Statistics in medicine
pub_type: 临床试验,杂志文章
doi:10.1002/sim.4780010103
更新日期:1982-01-01 00:00:00
abstract::Subjects in randomized controlled trials do not always comply to the treatment condition they have been assigned to. This may cause the estimated effect of the intervention to be biased and also affect efficiency, coverage of confidence intervals, and statistical power. In cluster randomized trials non-compliance may ...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.8351
更新日期:2019-11-20 00:00:00
abstract::In standard time-to-event or survival analysis, occurrence times of the event of interest are observed exactly or are right-censored, meaning that it is only known that the event occurred after the last observation time. There are numerous methods available for estimating the survival curve and for testing and estimat...
journal_title:Statistics in medicine
pub_type: 杂志文章,评审
doi:10.1002/(sici)1097-0258(19980130)17:2<219::aid-sim
更新日期:1998-01-30 00:00:00
abstract::Selection of dose for cancer patients treated with radiation therapy (RT) must balance the increased efficacy with the increased toxicity associated with higher dose. Historically, a single dose has been selected for a population of patients (e.g., all stage III non-small cell lung cancer). However, the availability o...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.6285
更新日期:2014-12-30 00:00:00
abstract::Machine learning techniques such as classification and regression trees (CART) have been suggested as promising alternatives to logistic regression for the estimation of propensity scores. The authors examined the performance of various CART-based propensity score models using simulated data. Hypothetical studies of v...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.3782
更新日期:2010-02-10 00:00:00
abstract::Although the frequentist paradigm has been the predominant approach to clinical trial design since the 1940s, it has several notable limitations. Advancements in computational algorithms and computer hardware have greatly enhanced the alternative Bayesian paradigm. Compared with its frequentist counterpart, the Bayesi...
journal_title:Statistics in medicine
pub_type: 杂志文章,评审
doi:10.1002/sim.5404
更新日期:2012-11-10 00:00:00
abstract::We consider statistical procedures for hypothesis testing of real valued functionals of matched pairs with missing values. In order to improve the accuracy of existing methods, we propose a novel multiplication combination procedure. Dividing the observed data into dependent (completely observed) pairs and independent...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.8178
更新日期:2019-07-30 00:00:00
abstract::We investigate population-averaged (PA) and cluster-specific (CS) associations for clustered binary logistic regression in the context of a longitudinal clinical trial that investigated the association between tooth-specific visual elastase kit results and periodontal disease progression within 26 weeks of follow-up. ...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4780140407
更新日期:1995-02-28 00:00:00
abstract::An observed confidence distribution is proposed as a measure of strength of evidence for practically equivalent efficacies of two treatments. The concept is independent of prior opinions about relevant sizes of a difference in efficacy. It also avoids retrospective power calculations for trials with missed recruitment...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4780071207
更新日期:1988-12-01 00:00:00
abstract::Tree-based methods have become popular for analyzing complex data structures where the primary goal is risk stratification of patients. Ensemble techniques improve the accuracy in prediction and address the instability in a single tree by growing an ensemble of trees and aggregating. However, in the process, individua...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4492
更新日期:2012-07-10 00:00:00
abstract::Although all clinical trials are designed and monitored using more than one endpoint, methods are needed to assure that decision criteria are chosen to reflect the clinically relevant tradeoffs that assure the trial's scientific integrity. This article presents a framework for the design and monitoring clinical trials...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.8696
更新日期:2020-11-20 00:00:00
abstract::The power prior has been widely used in many applications covering a large number of disciplines. The power prior is intended to be an informative prior constructed from historical data. It has been used in clinical trials, genetics, health care, psychology, environmental health, engineering, economics, and business. ...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.6728
更新日期:2015-12-10 00:00:00
abstract::Biomedical studies often measure variables with error. Examples in the literature include investigation of the association between the change in some outcome variable (blood pressure, cholesterol level etc.) and a set of explanatory variables (age, smoking status etc.). Typically, one fits linear regression models to ...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/(sici)1097-0258(19981130)17:22<2597::aid-s
更新日期:1998-11-30 00:00:00
abstract::This paper describes the Stoke Index which has been designed to give a global measure of disease activity in rheumatoid arthritis. The index is based on two objective laboratory measurements, one subjective and two semi-objective clinical measurements, chosen from 13 measurements using clinical judgement. Variable sel...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4780121206
更新日期:1993-06-30 00:00:00
abstract::In this work, we describe a two-stage sampling design to estimate the infection prevalence in a population. In the first stage, an imperfect diagnostic test was performed on a random sample of the population. In the second stage, a different imperfect test was performed in a stratified random sample of the first sampl...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.6545
更新日期:2015-11-10 00:00:00
abstract::We applied a computationally practical form of probit analysis for multiple response variables to data on early childhood development of four psychiatric disorders: disruptive disorders (DD-attention deficit disorders, oppositional defiant disorder, conduct disorder); adjustment disorders (ADJ); emotional disorders (E...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/(sici)1097-0258(19981115)17:21<2487::aid-s
更新日期:1998-11-15 00:00:00
abstract:BACKGROUND:The need to deliver interventions targeting multiple diseases in a cost-effective manner calls for integrated disease control efforts. Consequently, maps are required that show where the risk of co-infection is particularly high. Co-infection risk is preferably estimated via Bayesian geostatistical multinomi...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4243
更新日期:2011-06-30 00:00:00
abstract::This field study sought to measure the effects of dental delivery and school-based, dental health education on use of dental health care by children in grades K-6. We attempted to control for two potential confounding factors by an approximate randomization of children into treatment groups with stratification on grad...
journal_title:Statistics in medicine
pub_type: 临床试验,杂志文章,随机对照试验
doi:10.1002/sim.4780020107
更新日期:1983-01-01 00:00:00
abstract::We describe rank-based approaches to assess principal stratification treatment effects in studies where the outcome of interest is only well-defined in a subgroup selected after randomization. Our methods are sensitivity analyses, in that estimands are identified by fixing a parameter and then we investigate the sensi...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.5849
更新日期:2013-11-20 00:00:00
abstract::Recently, Wu and Follmann developed summary measures to adjust for informative drop-out in longitudinal studies where drop-out depends on the underlying true value of the response. In this paper we evaluate these procedures in the common situation where drop-out depends on the observed responses. We also discuss vario...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/1097-0258(20010115)20:1<93::aid-sim655>3.0
更新日期:2001-01-15 00:00:00
abstract::The 'landmark' and 'Simon and Makuch' non-parametric estimators of the survival function are commonly used to contrast the survival experience of time-dependent treatment groups in applications such as stem cell transplant versus chemotherapy in leukemia. However, the theoretical survival functions corresponding to th...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.6765
更新日期:2016-03-30 00:00:00
abstract::In population-based case-control studies, an attempt is made to identify all incident cases diagnosed in a specified population during a fixed time interval. Assuming that this goal is met allows one to obtain measures of risk other than relative risks. In this paper, we describe three approaches to estimate exposure-...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4780130526
更新日期:1994-03-15 00:00:00
abstract::Generalized linear models may be extended in several ways. This paper describes five such extensions: (i) generalized additive models; (ii) the use of quasi-likelihood; (iii) joint modelling of mean and dispersion; (iv) introduction of extra random components to give hierarchical generalized linear models; (v) modelli...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/(sici)1097-0258(19981215)17:23<2747::aid-s
更新日期:1998-12-15 00:00:00
abstract::In the analysis of survival data, there are often competing events that preclude an event of interest from occurring. Regression analysis with competing risks is typically undertaken using a cause-specific proportional hazards model. However, modern alternative methods exist for the analysis of the subdistribution haz...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4123
更新日期:2011-03-15 00:00:00
abstract::Cancer immunotherapy trials have two special features: a delayed treatment effect and a cure rate. Both features violate the proportional hazard model assumption and ignoring either one of the two features in an immunotherapy trial design will result in substantial loss of statistical power. To properly design immunot...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.8440
更新日期:2020-03-15 00:00:00
abstract::Most phase I dose-finding methods in oncology aim to find the maximum-tolerated dose from a set of prespecified doses. However, in practice, because of a lack of understanding of the true dose-toxicity relationship, it is likely that none of these prespecified doses are equal or reasonably close to the true maximum-to...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.6933
更新日期:2016-09-10 00:00:00