Abstract：
:Treatments are frequently evaluated in terms of their effect on patient survival. In settings where randomization of treatment is not feasible, observational data are employed, necessitating correction for covariate imbalances. Treatments are usually compared using a hazard ratio. Most existing methods which quantify the treatment effect through the survival function are applicable to treatments assigned at time 0. In the data structure of our interest, subjects typically begin follow-up untreated; time-until-treatment, and the pretreatment death hazard are both heavily influenced by longitudinal covariates; and subjects may experience periods of treatment ineligibility. We propose semiparametric methods for estimating the average difference in restricted mean survival time attributable to a time-dependent treatment, the average effect of treatment among the treated, under current treatment assignment patterns. The pre- and posttreatment models are partly conditional, in that they use the covariate history up to the time of treatment. The pre-treatment model is estimated through recently developed landmark analysis methods. For each treated patient, fitted pre- and posttreatment survival curves are projected out, then averaged in a manner which accounts for the censoring of treatment times. Asymptotic properties are derived and evaluated through simulation. The proposed methods are applied to liver transplant data in order to estimate the effect of liver transplantation on survival among transplant recipients under current practice patterns.
journal_name
Biometricsjournal_title
Biometricsauthors
Gong Q,Schaubel DEdoi
10.1111/biom.12542subject
Has Abstractpub_date
2017-03-01 00:00:00pages
134-144issue
1eissn
0006-341Xissn
1541-0420journal_volume
73pub_type
杂志文章相关文献
BIOMETRICS文献大全abstract：:At any age the mean residual life function gives the expected remaining life at that age. Reliabilists and biometricians have found it useful to categorize failure distributions by the monotonicity properties of the mean residual life function. Hollander and Proschan (1975, Biometrika 62, 585-593) have derived tests o...
journal_title：Biometrics
pub_type： 杂志文章
doi：
更新日期：1983-03-01 00:00:00
abstract：:Petersen-type mark-recapture experiments are often used to estimate the number of fish or other animals in a population moving along a set migration route. A first sample of individuals is captured at one location, marked, and returned to the population. A second sample is then captured farther along the route, and in...
journal_title：Biometrics
pub_type： 杂志文章
doi：10.1111/j.1541-0420.2011.01599.x
更新日期：2011-12-01 00:00:00
abstract：:This paper presents the development, application and evaluation of a stochastic model of the frequency of occurrence of transient ischemic attacks (TIAs). TIAs occur during periods of abnormal arterial activity. The TIAs which occur during a single period of abnormal activity are called a cluster of TIAs. Thus, the nu...
journal_title：Biometrics
pub_type： 临床试验,杂志文章
doi：
更新日期：1980-03-01 00:00:00
abstract：:In this article, we propose a new statistical method-MutRSeq-for detecting differentially expressed single nucleotide variants (SNVs) based on RNA-seq data. Specifically, we focus on nonsynonymous mutations and employ a hierarchical likelihood approach to jointly model observed mutation events as well as read count me...
journal_title：Biometrics
pub_type： 杂志文章
doi：10.1111/biom.12548
更新日期：2017-03-01 00:00:00
abstract：:Studies using a series of increasing doses of a compound, including a zero dose control, are often conducted to study the effect of the compound on the response of interest. For a one-way design, Tukey et al. (1985, Biometrics 41, 295-301) suggested assessing trend by examining the slopes of regression lines under ari...
journal_title：Biometrics
pub_type： 杂志文章
doi：10.1111/j.0006-341x.1999.00460.x
更新日期：1999-06-01 00:00:00
abstract：:Let Yi be an ni X 1 vector of observations, Xi an ni X p matrix of known values, and beta an unknown p X 1 with the structure Yi = Xi beta + epsilon i, where the covariance matrix of epsilon i is of intra-class form, that is Cov (epsilon i) = sigma2[(1 - rho) Ii + rho e i e i'] where Ii is the ni X ni identity matrix ...
journal_title：Biometrics
pub_type： 杂志文章
doi：
更新日期：1975-09-01 00:00:00
abstract：:We investigate two-stage parametric and two-stage semi-parametric estimation procedures for the association parameter in copula models for bivariate survival data where censoring in either or both components is allowed. We derive asymptotic properties of the estimators and compare their performance by simulations. Bot...
journal_title：Biometrics
pub_type： 杂志文章
doi：
更新日期：1995-12-01 00:00:00
abstract：:Estimates of waterfowl demographic parameters often come from resighting studies where birds fit with individually identifiable neck collars are resighted at a distance. Concerns have been raised about the effects of collar loss on parameter estimates, and the reliability of extrapolating from collared individuals to ...
journal_title：Biometrics
pub_type： 杂志文章
doi：10.1111/j.0006-341X.2004.00245.x
更新日期：2004-12-01 00:00:00
abstract：:A model specified in terms of linear models for marginal logits and linear models for log-odds ratios is proposed for the analysis of two-period binary cross-over experiments. Hypothesis testing and parameter estimation are facilitated by standard likelihood methodology. Two examples are used to illustrate how the mod...
journal_title：Biometrics
pub_type： 杂志文章
doi：
更新日期：1993-12-01 00:00:00
abstract：:This paper presents a comparison of three methods of parameter estimation in analysis of linkage between a quantitative trait locus (QTL) and a marker locus: maximum likelihood, mean square for trait cumulative distribution function, and method of moments, employing simulated backcross data. The sensitivity of estimat...
journal_title：Biometrics
pub_type： 杂志文章
doi：
更新日期：1996-06-01 00:00:00
abstract：:We consider hidden Markov models as a versatile class of models for weakly dependent random phenomena. The topic of the present paper is likelihood-ratio testing for hidden Markov models, and we show that, under appropriate conditions, the standard asymptotic theory of likelihood-ratio tests is valid. Such tests are c...
journal_title：Biometrics
pub_type： 杂志文章
doi：10.1111/j.0006-341x.2000.00742.x
更新日期：2000-09-01 00:00:00
abstract：:Prognostic models in survival analysis typically aim to describe the association between patient covariates and future outcomes. More recently, efforts have been made to include covariate information that is updated over time. However, there exists as yet no standard approach to assess the predictive accuracy of such ...
journal_title：Biometrics
pub_type： 杂志文章
doi：10.1111/j.1541-0420.2007.00889.x
更新日期：2008-06-01 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：: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：:Variable selection for recovering sparsity in nonadditive and nonparametric models with high-dimensional variables has been challenging. This problem becomes even more difficult due to complications in modeling unknown interaction terms among high-dimensional variables. There is currently no variable selection method ...
journal_title：Biometrics
pub_type： 杂志文章
doi：10.1111/biom.12518
更新日期：2016-12-01 00:00:00
abstract：:A procedure is given for estimating the ratio of the means of two populations using the data from two independent random samples when the observations are normally distributed with population variances that are related to the population means. ...
journal_title：Biometrics
pub_type： 杂志文章
doi：
更新日期：1985-03-01 00:00:00
abstract：:We consider the problem of comparing two outcome measures when the pairs are clustered. Using the general principle of within-cluster resampling, we obtain a novel signed-rank test for clustered paired data. We show by a simple informative cluster size simulation model that only our test maintains the correct size und...
journal_title：Biometrics
pub_type： 杂志文章
doi：10.1111/j.1541-0420.2007.00923.x
更新日期：2008-06-01 00:00:00
abstract：:A method purporting to provide optimal allocations in bioequivalence studies fails to do so on both statistical and practical grounds. Reasons as to why this is so are given. ...
journal_title：Biometrics
pub_type： 评论,杂志文章
doi：10.1111/j.0006-341x.1999.01314.x
更新日期：1999-12-01 00:00:00
abstract：:Moment methods for analyzing repeated binary responses have been proposed by Liang and Zeger (1986, Biometrika 73, 13-22), and extended by Prentice (1988, Biometrics 44, 1033-1048). In their generalized estimating equations (GEE), both Liang and Zeger (1986) and Prentice (1988) estimate the parameters associated with ...
journal_title：Biometrics
pub_type： 杂志文章
doi：
更新日期：1994-03-01 00:00:00
abstract：:The characteristics of deleterious genes have been of great interest in both theory and practice in genetics. Because of the complex genetic mechanism of these deleterious genes, most current studies try to estimate the overall magnitude of mortality effects on a population, which is characterized classically by the n...
journal_title：Biometrics
pub_type： 杂志文章
doi：10.1111/j.0006-341x.1999.00376.x
更新日期：1999-06-01 00:00:00
abstract：:The estimation of maternal genetic variances by a multivariate maximum likelihood method is discussed. As an illustration the method is applied to data on Tribolium using a model based on partitioning the maternal genetic effect into additive and dominance components. An alternative model due to Falconer (1965) is als...
journal_title：Biometrics
pub_type： 杂志文章
doi：
更新日期：1976-12-01 00:00:00
abstract：:Computer simulation has been used to compare four methods for calculating confidence intervals for simple rate ratios estimated from cohort studies. The method proposed by Cornfield (1956. In Proceedings of the Third Berkeley Symposium on Mathematical Statistics and Probability. Vol. IV, 135-148) for interval estimati...
journal_title：Biometrics
pub_type： 杂志文章
doi：
更新日期：1983-06-01 00:00:00
abstract：:We explore the use of a posterior predictive loss criterion for model selection for incomplete longitudinal data. We begin by identifying a property that most model selection criteria for incomplete data should consider. We then show that a straightforward extension of the Gelfand and Ghosh (1998, Biometrika, 85, 1-11...
journal_title：Biometrics
pub_type： 杂志文章
doi：10.1111/j.1541-0420.2012.01766.x
更新日期：2012-12-01 00:00:00
abstract：:In principle, G-estimation is an attractive approach for dealing with confounding by variables affected by treatment. It has rarely been applied for estimation of the effects of treatment on failure-time outcomes. Part of this is due to artificial censoring, an analytic device which considers some subjects who actuall...
journal_title：Biometrics
pub_type： 杂志文章
doi：10.1111/j.1541-0420.2011.01656.x
更新日期：2012-03-01 00:00:00
abstract：:Cancer population studies based on cancer registry databases are widely conducted to address various research questions. In general, cancer registry databases do not collect information on cause of death. The net survival rate is defined as the survival rate if a subject would not die for any causes other than cancer....
journal_title：Biometrics
pub_type： 杂志文章
doi：10.1111/biom.12568
更新日期：2017-03-01 00:00:00
abstract：:Receiver operating characteristic (ROC) analysis is widely used to evaluate the performance of diagnostic tests with continuous or ordinal responses. A popular study design for assessing the accuracy of diagnostic tests involves multiple readers interpreting multiple diagnostic test results, called the multi-reader, m...
journal_title：Biometrics
pub_type： 杂志文章
doi：10.1111/biom.12240
更新日期：2014-12-01 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：:Array-based CGH experiments are designed to detect genomic aberrations or regions of DNA copy-number variation that are associated with an outcome, typically a state of disease. Most of the existing statistical methods target on detecting DNA copy number variations in a single sample or array. We focus on the detectio...
journal_title：Biometrics
pub_type： 杂志文章
doi：10.1111/biom.12478
更新日期：2016-09-01 00:00:00
abstract：:We propose methods for Bayesian inference for a new class of semiparametric survival models with a cure fraction. Specifically, we propose a semiparametric cure rate model with a smoothing parameter that controls the degree of parametricity in the right tail of the survival distribution. We show that such a parameter ...
journal_title：Biometrics
pub_type： 杂志文章
doi：10.1111/j.0006-341x.2001.00383.x
更新日期：2001-06-01 00:00:00
abstract：:Consider case control analysis with a dichotomous exposure variable that is subject to misclassification. If the classification probabilities are known, then methods are available to adjust odds-ratio estimates in light of the misclassification. We study the realistic scenario where reasonable guesses, but not exact v...
journal_title：Biometrics
pub_type： 杂志文章
doi：10.1111/j.0006-341x.2001.00598.x
更新日期：2001-06-01 00:00:00
