Abstract:
:In this paper statistical methods are proposed to estimate the distribution of a CD4 T-cell number at the time of a clinical AIDS endpoint from serial measurements of CD4 T-cell values in a cohort study. The statistical formulation of the problem is that of survival analysis with interval censored data, but in which the endpoints are obtained with measurement error. A measurement error likelihood is developed, assuming normality of the CD4 distribution at AIDS. A maximum likelihood estimation procedure and a Gibbs sampling approach are implemented.
journal_name
Stat Medjournal_title
Statistics in medicineauthors
Taylor JM,Kim DKdoi
10.1002/sim.4780131915subject
Has Abstractpub_date
1994-10-15 00:00:00pages
2059-66issue
19-20eissn
0277-6715issn
1097-0258journal_volume
13pub_type
杂志文章abstract::We discuss the use of the trichotomous logistic model to discriminate between patients with gastrointestinal (GI) cancer, patients with benign GI disease and 'normal' subjects, using symptoms and the concentrations of some serum proteins that are potentially indicative of malignancy as covariates. A parsimonious model...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4780040313
更新日期:1985-07-01 00:00:00
abstract::We present a new method of detection and inference for spatial clusters of a disease. To avoid ad hoc procedures to test for clustering, we have a clearly defined alternative hypothesis and our test statistic is based on the likelihood ratio. The proposed test can detect clusters of any size, located anywhere in the s...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4780140809
更新日期:1995-04-30 00:00:00
abstract::In the comparison of two or more treatment groups to a control group, consider a study with non-decreasing repeated measurements of the same characteristic taken over a common set of time points for each subject. Based on the vector of possibly incomplete responses from each subject, this paper considers asymptoticall...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/(SICI)1097-0258(19961215)15:23<2509::AID-S
更新日期:1996-12-15 00:00:00
abstract::While genome-wide association studies (GWASs) have been widely used to uncover associations between diseases and genetic variants, standard SNP-level GWASs often lack the power to identify SNPs that individually have a moderate effect size but jointly contribute to the disease. To overcome this problem, pathway-based ...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.8442
更新日期:2020-03-15 00:00:00
abstract::We propose a joint model to analyze the structure and intensity of the association between longitudinal measurements of an ordinal marker and time to a relevant event. The longitudinal process is defined in terms of a proportional-odds cumulative logit model. Time-to-event is modeled through a left-truncated proportio...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.7065
更新日期:2016-12-10 00:00:00
abstract::This paper presents a mixture model which combines features of the usual Cox proportional hazards model with those of a class of models, known as mixtures-of-experts. The resulting model is more flexible than the usual Cox model in the sense that the log hazard ratio is allowed to vary non-linearly as a function of th...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/(sici)1097-0258(19990515)18:9<1119::aid-si
更新日期:1999-05-15 00:00:00
abstract::We propose a new, less costly, design to test the equivalence of digital versus analogue mammography in terms of sensitivity and specificity. Because breast cancer is a rare event among asymptomatic women, the sample size for testing equivalence of sensitivity is larger than that for testing equivalence of specificity...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/(sici)1097-0258(19981015)17:19<2219::aid-s
更新日期:1998-10-15 00:00:00
abstract::Longitudinal studies are often concerned with estimating the recurrence rate of a non-fatal event. In many cases, only the total number of events occurring during successive time intervals is known. We compared a mixed Poisson-gamma regression method proposed by Thall and a quasi-likelihood method proposed by Zeger an...
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.4780121406
更新日期:1993-07-30 00:00:00
abstract::In cancer clinical trials, patients often experience a recurrence of disease prior to the outcome of interest, overall survival. Additionally, for many cancers, there is a cured fraction of the population who will never experience a recurrence. There is often interest in how different covariates affect the probability...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.6056
更新日期:2014-05-10 00:00:00
abstract::Among subjects who have experienced a biological event, such as menarche, menopause or a delivery, one cannot distinguish the effects of time since the event from age at the event due to the linear dependency among these time variables and age at study ('current age'). This is a well-known problem that also exists in ...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/(SICI)1097-0258(19960730)15:14<1545::AID-S
更新日期:1996-07-30 00:00:00
abstract::The log-rank test is the most powerful non-parametric test for detecting a proportional hazards alternative and thus is the most commonly used testing procedure for comparing time-to-event distributions between different treatments in clinical trials. When the log-rank test is used for the primary data analysis, the s...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.3501
更新日期:2009-02-28 00:00:00
abstract::In the field of cluster detection, a weighted normal model-based scan statistic was recently developed to analyze regional continuous data and to evaluate the clustering pattern of pre-defined cells (such as state, county, tract, school, hospital) that include many individuals. The continuous measures of interest are,...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.3990
更新日期:2010-10-15 00:00:00
abstract::Clinical studies that involve the recording of two or more distinct and well-defined events on each subject give rise to multiple event data. Treatment comparisons are usually reported in univariate analyses of time to first event or number of events observed. However, this approach may not uncover the 'full story' of...
journal_title:Statistics in medicine
pub_type: 临床试验,杂志文章,多中心研究,随机对照试验
doi:10.1002/(sici)1097-0258(19970430)16:8<941::aid-sim
更新日期:1997-04-30 00:00:00
abstract::In recent years randomized trials designed to establish non-inferiority of a new treatment as compared to a standard one have been more widely used. Two-sample statistics have been proposed for this equivalence testing problem. However, they are not suited to situations where a long-term survivor fraction is expected....
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.1453
更新日期:2003-03-30 00:00:00
abstract::Appropriate methods for meta-regression applied to a set of clinical trials, and the limitations and pitfalls in interpretation, are insufficiently recognized. Here we summarize recent research focusing on these issues, and consider three published examples of meta-regression in the light of this work. One principal m...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.1187
更新日期:2002-06-15 00:00:00
abstract::New combination regimens evaluated in phase II cancer clinical trials often show promising results compared to the standard therapy for a disease system. Selection of patients with a better prognosis can be a prominent factor for this optimism. For most disease systems, prognostic variables that are related to the out...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.706
更新日期:2001-03-30 00:00:00
abstract::To benefit Alzheimer's disease research, a central data co-ordinating centre (CDCC) is planned that will systematically collect data from 27 Alzheimer's disease centres (ADCs) located nationwide. This CDCC will combine, analyse and disseminate epidemiologic, demographic, clinical and neuropathological data to research...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/(sici)1097-0258(20000615/30)19:11/12<1453:
更新日期:2000-06-15 00:00:00
abstract::We have developed a method to longitudinally classify subjects into two or more prognostic groups using longitudinally observed values of markers related to the prognosis. We assume the availability of a training data set where the subjects' allocation into the prognostic group is known. The proposed method proceeds i...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.3849
更新日期:2010-12-30 00:00:00
abstract::Cancer patients, chronic kidney disease patients, and subjects infected with HIV are routinely monitored over time using biomarkers that represent key health status indicators. Furthermore, biomarkers are frequently used to guide initiation of new treatments or to inform changes in intervention strategies. Since key m...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.7675
更新日期:2018-08-15 00:00:00
abstract::Statistical modeling methods have had increasing use in drug disposition studies, both to estimate pharmacokinetic parameters and to develop regression models that relate these parameter estimates to patient characteristics. These methods are particularly flexible as they allow non-linearity and sparse within-patient ...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/(sici)1097-0258(19970615)16:11<1241::aid-s
更新日期:1997-06-15 00:00:00
abstract::This paper reviews Bayesian strategies for monitoring clinical trial data. It focuses on a Bayesian stochastic curtailment method based on the predictive probability of observing a clinically significant outcome at the scheduled end of the study given the observed data. The proposed method is applied to derive efficac...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.2204
更新日期:2006-07-15 00:00:00
abstract::This paper reviews several emerging and recurrent issues relating to the drug development process. These emerging issues include changes to the FDA regulatory environment, internationalization of drug development, advances in computer technology and visualization tools, and efforts to incorporate meta-analysis methodo...
journal_title:Statistics in medicine
pub_type: 杂志文章,评审
doi:10.1002/(sici)1097-0258(19990915/30)18:17/18<2301:
更新日期:1999-09-15 00:00:00
abstract::Technologic advances give rise to new tests for detecting disease in many fields, including cancer and sexually transmitted disease. Before a new disease screening test is approved for public use, its accuracy should be shown to be better than or at least not inferior to an existing test. Standards do not yet exist fo...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.1058
更新日期:2002-03-30 00:00:00
abstract::Results from an analysis of traffic accidents from a study of the police records of four police stations in the Bangkok metropolis are presented. The main emphasis in this study was put on the development of a measure for traffic accident density. The traffic flow was estimated at the various study locations by traine...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4780142113
更新日期:1995-11-15 00:00:00
abstract::The aim of this paper is to demonstrate the effect of excluding incomplete observations and competing events when calculating cross-sectional measures of NHS waiting times, and to obtain a more accurate estimate of the 'time-to-admission' of those listed on NHS waiting lists using life-table methods. The official 'tim...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/1097-0258(20000815)19:15<2037::aid-sim606>
更新日期:2000-08-15 00:00:00
abstract::A common problem encountered in many medical applications is the comparison of survival curves. Often, rather than comparison of the entire survival curves, interest is focused on the comparison at a fixed point in time. In most cases, the naive test based on a difference in the estimates of survival is used for this ...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.2864
更新日期:2007-10-30 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::The estimation of attributable risk in the presence of confounding and effect modification is studied in this paper. Different adjustment methods for the attributable risk are reviewed. The results of a stimulation study comparing these methods under the unrestricted multinomial sampling model are reported. From the s...
journal_title:Statistics in medicine
pub_type: 杂志文章,评审
doi:10.1002/sim.4780111606
更新日期:1992-12-01 00:00:00
abstract::Mesothelioma is a rare cancer caused by exposure to asbestos. Belgium has a known long history of asbestos production, resulting in one of the highest mesothelioma mortality rates worldwide. While the production of asbestos has stopped completely, the long latency period of mesothelioma, which can fluctuate between 20...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.8697
更新日期:2020-11-20 00:00:00
abstract::Diagnostic problems in medicine are sometimes polytomous, meaning that the outcome has more than two distinct categories. For example, ovarian tumors can be benign, borderline, primary invasive, or metastatic. Extending the main measure of binary discrimination, the c-statistic or area under the ROC curve, to nominal ...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.5321
更新日期:2012-10-15 00:00:00