Abstract：
:This paper focuses on the methodology developed for analyzing a multivariate interval-censored data set from an AIDS observational study. A purpose of the study was to determine the natural history of the opportunistic infection cytomeglovirus (CMV) in an HIV-infected individual. For this observational study, laboratory tests were performed at scheduled clinic visits to test for the presence of the CMV virus in the blood and in the urine (called CMV shedding in the blood and urine). The study investigators were interested in determining whether the stage of HIV disease at study entry was predictive of an increased risk for CMV shedding in either the blood or the urine. If all patients had made each clinic visit, the data would be multivariate grouped failure time data and published methods could be used. However, many patients missed several visits, and when they returned, their lab tests indicated a change in their blood and/or urine CMV shedding status, resulting in interval-censored failure time data. This paper outlines a method for applying the proportional hazards model to the analysis of multivariate interval-censored failure time data from a study of CMV in HIV-infected patients.
journal_name
Biometricsjournal_title
Biometricsauthors
Goggins WB,Finkelstein DMdoi
10.1111/j.0006-341x.2000.00940.xsubject
Has Abstractpub_date
2000-09-01 00:00:00pages
940-3issue
3eissn
0006-341Xissn
1541-0420journal_volume
56pub_type
杂志文章相关文献
BIOMETRICS文献大全abstract：:Because the number of patients waiting for organ transplants exceeds the number of organs available, a better understanding of how transplantation affects the distribution of residual lifetime is needed to improve organ allocation. However, there has been little work to assess the survival benefit of transplantation f...
journal_title：Biometrics
pub_type： 杂志文章
doi：10.1111/biom.12084
更新日期：2013-12-01 00:00:00
abstract：:In an effort to determine whether a particular treatment causes a particular outcome event, data are obtained from a database system that records events when they occur, and for such events, the system records exposure to the treatment. That is, the system records information about cases. The system provides no inform...
journal_title：Biometrics
pub_type： 杂志文章
doi：10.1111/j.0006-341X.2005.030920.x
更新日期：2005-03-01 00:00:00
abstract：:Dose-response models are intensively used in herbicide bioassays. Despite recent advancements in the development of new herbicides, statistical analyses are commonly based on asymptotic approximations that are sometimes poor. This paper presents the use of recent results in higher order asymptotics for likelihood-base...
journal_title：Biometrics
pub_type： 杂志文章
doi：10.1111/j.0006-341x.2000.01204.x
更新日期：2000-12-01 00:00:00
abstract：:We briefly review the major contribution of biometrics to genetics over the last century (population genetic models, familial correlations, segregation analysis, and gene mapping) and current areas of active research and then speculate about what problems will be tackled in the next century. ...
journal_title：Biometrics
pub_type： 社论,历史文章,评审
doi：10.1111/j.0006-341x.2000.00659.x
更新日期：2000-09-01 00:00:00
abstract：:In the evaluation of diagnostic accuracy of tests, a gold standard on the disease status is required. However, in many complex diseases, it is impossible or unethical to obtain such a gold standard. If an imperfect standard is used, the estimated accuracy of the tests would be biased. This type of bias is called imper...
journal_title：Biometrics
pub_type： 杂志文章
doi：10.1111/j.1541-0420.2005.00324.x
更新日期：2005-06-01 00:00:00
abstract：:We consider the problem of estimating a population size from successive catches taken during a removal experiment and propose two estimating functions approaches, the traditional quasi-likelihood (TQL) approach for dependent observations and the conditional quasi-likelihood (CQL) approach using the conditional mean an...
journal_title：Biometrics
pub_type： 杂志文章
doi：10.1111/j.0006-341x.1999.01263.x
更新日期：1999-12-01 00:00:00
abstract：:A mean residual life function is the average remaining life of a surviving subject, as it varies with time. The proportional mean residual life model was proposed by Oakes and Dasu (1990, Biometrika77, 409-410) in regression analysis to study its association with related covariates in absence of censoring. In this art...
journal_title：Biometrics
pub_type： 杂志文章
doi：10.1111/j.0006-341X.2005.030224.x
更新日期：2005-03-01 00:00:00
abstract：:The fitting of finite mixture models via the EM algorithm is considered for data which are available only in grouped form and which may also be truncated. A practical example is presented where a mixture of two doubly truncated log-normal distributions is adopted to model the distribution of the volume of red blood ce...
journal_title：Biometrics
pub_type： 杂志文章
doi：
更新日期：1988-06-01 00:00:00
abstract：:The availability of data in longitudinal studies is often driven by features of the characteristics being studied. For example, clinical databases are increasingly being used for research to address longitudinal questions. Because visit times in such data are often driven by patient characteristics that may be related...
journal_title：Biometrics
pub_type： 杂志文章
doi：10.1111/biom.12501
更新日期：2016-12-01 00:00:00
abstract：:The distance between homologous DNA sequences of two species is proposed to be -1/4 ln[det(P)], where P is the conditional probability matrix specifying the proportions of the various nucleotides in the second sequence, corresponding to each of the four nucleotides in the first sequence. A probability model is describ...
journal_title：Biometrics
pub_type： 杂志文章
doi：
更新日期：1987-06-01 00:00:00
abstract：:Development of HIV resistance mutations is a major cause for failure of antiretroviral treatment. This article proposes a method for jointly modeling the processes of viral genetic changes and treatment failure. Because the viral genome is measured with uncertainty, a hidden Markov model is used to fit the viral genet...
journal_title：Biometrics
pub_type： 杂志文章
doi：10.1111/j.1541-0420.2006.00635.x
更新日期：2007-03-01 00:00:00
abstract：:The objective of this article is to develop a hypothesis-testing procedure to determine whether a common source outbreak has ended. We consider the case when neither the calendar date of exposure to the pathogen nor the exact incubation period distribution is known. The hypothesis-testing procedure is based on the spa...
journal_title：Biometrics
pub_type： 杂志文章
doi：10.1111/j.1541-0420.2005.00421.x
更新日期：2006-03-01 00:00:00
abstract：:In this article, we present an estimation approach for solving nonlinear constrained generalized estimating equations that can be implemented using object-oriented software for nonlinear programming, such as nlminb in Splus or fmincon and lsqnonlin in Matlab. We show how standard estimating equation theory includes th...
journal_title：Biometrics
pub_type： 杂志文章
doi：10.1111/j.0006-341x.2000.01268.x
更新日期：2000-12-01 00:00:00
abstract：:Receiver operating characteristic (ROC) curves are frequently used to assess the usefulness of diagnostic markers. When several diagnostic markers are available, they can be combined by a best linear combination: that is, when the area under the ROC curve of this combination is maximized among all possible linear comb...
journal_title：Biometrics
pub_type： 杂志文章
doi：
更新日期：1997-06-01 00:00:00
abstract：:This note provides a discussion on the manuscript by Wang et al. (2005) who aim to robustify inference for longitudinal data analysis by replacing the ordinary generalized estimating function with an influence-bounded, possibly biased, version. To adjust for the bias of the ensuing robust estimator, the authors provid...
journal_title：Biometrics
pub_type： 信件
doi：10.1111/biom.13263
更新日期：2020-09-01 00:00:00
abstract：:Statistical models that include random effects are commonly used to analyze longitudinal and correlated data, often with the assumption that the random effects follow a Gaussian distribution. Via theoretical and numerical calculations and simulation, we investigate the impact of misspecification of this distribution o...
journal_title：Biometrics
pub_type： 杂志文章
doi：10.1111/j.1541-0420.2010.01435.x
更新日期：2011-03-01 00:00:00
abstract：:Pharmacovigilance systems aim at early detection of adverse effects of marketed drugs. They maintain large spontaneous reporting databases for which several automatic signaling methods have been developed. One limit of those methods is that the decision rules for the signal generation are based on arbitrary thresholds...
journal_title：Biometrics
pub_type： 杂志文章
doi：10.1111/j.1541-0420.2009.01262.x
更新日期：2010-03-01 00:00:00
abstract：:An individual's health condition can affect the frequency and intensity of episodes that can occur repeatedly and that may be related to an event time of interest. For example, bleeding episodes during pregnancy may indicate problems predictive of preterm delivery. Motivated by this application, we propose a joint mod...
journal_title：Biometrics
pub_type： 杂志文章
doi：10.1111/j.1541-0420.2006.00720.x
更新日期：2007-06-01 00:00:00
abstract：:R. A. Fisher is widely respected for his contributions to both statistics and genetics. For instance, his 1930 text on The Genetical Theory of Natural Selection remains a watershed contribution in that area. Fisher's subsequent research led him to study the work of (Johann) Gregor Mendel, the 19th century monk who fir...
journal_title：Biometrics
pub_type： 传,历史文章,杂志文章,评审
doi：
更新日期：1990-12-01 00:00:00
abstract：:We estimate how the effect of antiretroviral treatment depends on the time from HIV-infection to initiation of treatment, using observational data. A major challenge in making inferences from such observational data arises from biases associated with the nonrandom assignment of treatment, for example bias induced by d...
journal_title：Biometrics
pub_type： 杂志文章
doi：10.1111/j.1541-0420.2011.01738.x
更新日期：2012-09-01 00:00:00
abstract：:Asbestos exposure is a well-known risk factor for various lung diseases, and when they occur, workmen's compensation boards need to make decisions concerning the probability the cause is work related. In the absence of a definitive work history, measures of short and long asbestos fibers as well as counts of asbestos ...
journal_title：Biometrics
pub_type： 杂志文章
doi：10.1111/j.1541-0420.2009.01279.x
更新日期：2010-06-01 00:00:00
abstract：:Highly active antiretroviral therapy (HAART) has proved efficient in increasing CD4 counts in many randomized clinical trials. Because randomized trials have some limitations (e.g., short duration, highly selected subjects), it is interesting to assess the effect of treatments using observational studies. This is chal...
journal_title：Biometrics
pub_type： 杂志文章
doi：10.1111/biom.12564
更新日期：2017-03-01 00:00:00
abstract：:We propose a design strategy for single-arm clinical trials in which the goals are to find a dose of an experimental treatment satisfying both safety and efficacy requirements, treat a sufficiently large number of patients to estimate the rates of these events at the selected dose with a given reliability, and stop th...
journal_title：Biometrics
pub_type： 杂志文章
doi：
更新日期：1998-03-01 00:00:00
abstract：:The validation of surrogate endpoints has been studied by Prentice (1989, Statistics in Medicine 8, 431-440) and Freedman, Graubard, and Schatzkin (1992, Statistics in Medicine 11, 167-178). We extended their proposals in the cases where the surrogate and the final endpoints are both binary or normally distributed. Le...
journal_title：Biometrics
pub_type： 杂志文章
doi：
更新日期：1998-09-01 00:00:00
abstract：:In multivariate survival analysis, investigators are often interested in testing for heterogeneity among clusters, both overall and within specific classes. We represent different hypotheses about the heterogeneity structure using a sequence of gamma frailty models, ranging from a null model with no random effects to ...
journal_title：Biometrics
pub_type： 杂志文章
doi：10.1111/j.0006-341X.2004.00179.x
更新日期：2004-06-01 00:00:00
abstract：:The variogram is a standard tool in the analysis of spatial data, and its shape provides useful information on the form of spatial correlation that may be present. However, it is also useful to be able to assess the evidence for the presence of any spatial correlation. A method of doing this, based on an assessment of...
journal_title：Biometrics
pub_type： 杂志文章
doi：10.1111/j.0006-341x.2001.00211.x
更新日期：2001-03-01 00:00:00
abstract：:In Western countries where food supply is satisfactory, consumers organize their diets around a large combination of foods. It is the purpose of this article to examine how recent nonnegative matrix factorization (NMF) techniques can be applied to food consumption data to understand these combinations. Such data are n...
journal_title：Biometrics
pub_type： 杂志文章
doi：10.1111/j.1541-0420.2011.01588.x
更新日期：2011-12-01 00:00:00
abstract：:This paper presents an approach to handling missing covariates in the generalized estimating equation (GEE) model for binary outcomes when the probability of missingness depends on the observed outcomes and covariates. The proposed method is to replace the missing quantities in the estimating function with consistent ...
journal_title：Biometrics
pub_type： 杂志文章
doi：
更新日期：1997-12-01 00:00:00
abstract：:The use of three periods in the two-treatment crossover design for clinical trials is considered. It is proposed that a series of such trials in a particular therapeutic area may establish the relevance of the crossover design in that area. Treatment sequences to be used in three-period two-treatment trials are discus...
journal_title：Biometrics
pub_type： 杂志文章
doi：
更新日期：1984-03-01 00:00:00
abstract：:In the calibration problem, the need to construct a confidence interval to estimate the unknown chi 0 arises when the null hypothesis of zero slope is rejected. Otherwise, the resulting confidence interval will be infinite to reflect the fact that the slope of the regression line may be zero. Under the condition of re...
journal_title：Biometrics
pub_type： 杂志文章
doi：
更新日期：1991-12-01 00:00:00
