Abstract：
:It is not, in general, possible to include all relevant risk factors in a model of survival or disease incidence. This heterogeneity must be accounted for in the interpretation, as it can imply otherwise unexpected results. This is illustrated by diabetic nephropathy, a serious complication experienced by some diabetic patients. A mathematical model with varying susceptibility can explain that the incidence increases until 20 years duration of diabetes and later decreases. The hospital-based data cover patients diagnosed during 1933-1972. They are interval censored, because early detection of nephropathy requires chemical analysis of urine samples. The data are consistent with a model where less than half of the patients are susceptible, and for each of these the hazard is increasing. The estimated degree of heterogeneity markedly depends on the assumed model. The dependence on age at onset and calendar time of onset is examined. The highest risk is seen at onset age 13-17 years, and the risk decreases with calendar time. The effect of covariates on the hazard is markedly different for the various models, but this is partly a matter of parametrization, as the disagreement is reduced by a reparametrization inspired by accelerated failure time models.
journal_name
Biometricsjournal_title
Biometricsauthors
Hougaard P,Myglegaard P,Borch-Johnsen Ksubject
Has Abstractpub_date
1994-12-01 00:00:00pages
1178-88issue
4eissn
0006-341Xissn
1541-0420journal_volume
50pub_type
杂志文章相关文献
BIOMETRICS文献大全abstract：:We describe a logistic-bivariate normal mixture model for a two-state Markov chain in which each individual makes transitions between states according to a subject-specific transition probability matrix. The use of the bivariate normal mixing distribution facilitates inferences regarding the correlation of the random ...
journal_title：Biometrics
pub_type： 杂志文章
doi：
更新日期：1997-03-01 00:00:00
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：:Capture-recapture models are widely used to estimate demographic parameters of marked populations. Recently, this statistical theory has been extended to modeling dispersal of open populations. Multistate models can be used to estimate movement probabilities among subdivided populations if multiple sites are sampled. ...
journal_title：Biometrics
pub_type： 杂志文章
doi：10.1111/j.0006-341x.2001.00273.x
更新日期：2001-03-01 00:00:00
abstract：:Genomic data are often characterized by a moderate to large number of categorical variables observed for relatively few subjects. Some of the variables may be missing or noninformative. An example of such data is loss of heterozygosity (LOH), a dichotomous variable, observed on a moderate number of genetic markers. We...
journal_title：Biometrics
pub_type： 杂志文章
doi：10.1111/j.1541-0420.2006.00566.x
更新日期：2006-12-01 00:00:00
abstract：:In biomedical cohort studies for assessing the association between an outcome variable and a set of covariates, usually, some covariates can only be measured on a subgroup of study subjects. An important design question is-which subjects to select into the subgroup to increase statistical efficiency. When the outcome ...
journal_title：Biometrics
pub_type： 杂志文章
doi：10.1111/biom.13140
更新日期：2020-03-01 00:00:00
abstract：:We describe an exact, unconditional, non-randomized procedure for producing confidence intervals for the grand mean in a normal-normal random effects meta-analysis. The procedure targets meta-analyses based on too few primary studies, ≤ 7 , say, to ...
journal_title：Biometrics
pub_type： 杂志文章
doi：10.1111/biom.12998
更新日期：2019-06-01 00:00:00
abstract：:We consider methods for estimating the treatment effect and/or the covariate by treatment interaction effect in a randomized clinical trial under noncompliance with time-to-event outcome. As in Cuzick et al. (2007), assuming that the patient population consists of three (possibly latent) subgroups based on treatment p...
journal_title：Biometrics
pub_type： 杂志文章
doi：10.1111/biom.12472
更新日期：2016-09-01 00:00:00
abstract：:In many applications of generalized linear mixed models to multilevel data, it is of interest to test whether a random effects variance component is zero. It is well known that the usual asymptotic chi-square distribution of the likelihood ratio and score statistics under the null does not necessarily hold. In this no...
journal_title：Biometrics
pub_type： 杂志文章
doi：10.1111/j.1541-0420.2007.00775.x
更新日期：2007-09-01 00:00:00
abstract：:When testing the null hypothesis that treatment arm-specific survival-time distributions are equal, the log-rank test is asymptotically valid when the distribution of time to censoring is conditionally independent of randomized treatment group given survival time. We introduce a test of the null hypothesis for use whe...
journal_title：Biometrics
pub_type： 杂志文章
doi：10.1111/1541-0420.00059
更新日期：2003-09-01 00:00:00
abstract：:In the genetic study of complex traits, especially behavior related ones, such as smoking and alcoholism, usually several phenotypic measurements are obtained for the description of the complex trait, but no single measurement can quantify fully the complicated characteristics of the symptom because of our lack of und...
journal_title：Biometrics
pub_type： 杂志文章
doi：10.1111/j.1541-0420.2009.01235.x
更新日期：2010-03-01 00:00:00
abstract：:Interference occurs between individuals when the treatment (or exposure) of one individual affects the outcome of another individual. Previous work on causal inference methods in the presence of interference has focused on the setting where it is a priori assumed that there is "partial interference," in the sense that...
journal_title：Biometrics
pub_type： 杂志文章
doi：10.1111/biom.13125
更新日期：2020-03-01 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：:As ultra high-dimensional longitudinal data are becoming ever more apparent in fields such as public health and bioinformatics, developing flexible methods with a sparse model is of high interest. In this setting, the dimension of the covariates can potentially grow exponentially as ...
journal_title：Biometrics
pub_type： 杂志文章
doi：10.1111/biom.13348
更新日期：2020-08-04 00:00:00
abstract：:We derive semiparametric methods for estimating and testing treatment effects when censored recurrent event data are available over multiple periods. These methods are based on estimating functions motivated by a working "mixed-Poisson" assumption under which conditioning can eliminate subject-specific random effects....
journal_title：Biometrics
pub_type： 杂志文章
doi：10.1111/j.1541-0420.2005.00357.x
更新日期：2005-09-01 00:00:00
abstract：:Currently, the design of group sequential clinical trials requires choosing among several distinct design categories, design scales, and strategies for determining stopping rules. This approach can limit the design selection process so that clinical issues are not fully addressed. This paper describes a family of desi...
journal_title：Biometrics
pub_type： 杂志文章
doi：10.1111/j.0006-341x.1999.00874.x
更新日期：1999-09-01 00:00:00
abstract：:Methods for modeling and mapping spatial variation in disease risk continue to motivate much research. In particular, spatial analyses provide a useful tool for exploring geographical heterogeneity in health outcomes, and consequently can yield clues as to disease etiology, direct public health management, and generat...
journal_title：Biometrics
pub_type： 杂志文章
doi：10.1111/j.1541-0420.2008.01193.x
更新日期：2009-12-01 00:00:00
abstract：:Large amounts of longitudinal health records are now available for dynamic monitoring of the underlying processes governing the observations. However, the health status progression across time is not typically observed directly: records are observed only when a subject interacts with the system, yielding irregular and...
journal_title：Biometrics
pub_type： 杂志文章
doi：10.1111/biom.13261
更新日期：2020-03-11 00:00:00
abstract：:The method based on the Kolmogorov backward equations of Little (1995, Biometrics 51, 1278-1291) for computing hazard functions for the multistage carcinogenesis models fails when model parameters are time-dependent. In addition to suggesting an alternative method based on the Kolmogorov forward equation, this note hi...
journal_title：Biometrics
pub_type： 杂志文章
doi：
更新日期：1998-03-01 00:00:00
abstract：:In clinical studies, longitudinal biomarkers are often used to monitor disease progression and failure time. Joint modeling of longitudinal and survival data has certain advantages and has emerged as an effective way to mutually enhance information. Typically, a parametric longitudinal model is assumed to facilitate t...
journal_title：Biometrics
pub_type： 杂志文章
doi：10.1111/j.1541-0420.2007.00896.x
更新日期：2008-06-01 00:00:00
abstract：:When the observed data are contaminated with errors, the standard two-sample testing approaches that ignore measurement errors may produce misleading results, including a higher type-I error rate than the nominal level. To tackle this inconsistency, a nonparametric test is proposed for testing equality of two distribu...
journal_title：Biometrics
pub_type： 杂志文章
doi：10.1111/biom.13207
更新日期：2020-09-01 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：:New methods are developed for assessing the extent of interrater agreement when each unit to be rated is characterized by a (possibly empty) subset of a specified set of distinct nominal attributes. For such multiple attribute response data, a two-rater concordance statistic is derived, and associated statistical infe...
journal_title：Biometrics
pub_type： 杂志文章
doi：
更新日期：1989-09-01 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：:With advancements in technology, the collection of multiple types of measurements on a common set of subjects is becoming routine in science. Some notable examples include multimodal neuroimaging studies for the simultaneous investigation of brain structure and function and multi-omics studies for combining genetic an...
journal_title：Biometrics
pub_type： 杂志文章
doi：10.1111/biom.13351
更新日期：2020-08-13 00:00:00
abstract：:The first part of the article reviews the Data Augmentation algorithm and presents two approximations to the Data Augmentation algorithm for the analysis of missing-data problems: the Poor Man's Data Augmentation algorithm and the Asymptotic Data Augmentation algorithm. These two algorithms are then implemented in the...
journal_title：Biometrics
pub_type： 杂志文章
doi：
更新日期：1991-12-01 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：:The class of admissible tests for Hardy-Weinberg equilibrium in a multi-allelic system is characterized. The standard goodness-of-fit chi-square tests is shown to be admissible for systems of two or more alleles. The conditional probability distribution required to determine the exact significance level of this test i...
journal_title：Biometrics
pub_type： 杂志文章
doi：
更新日期：1980-03-01 00:00:00
abstract：:Mixed longitudinal growth data consists of several observations on a characteristic over a limited age range for each individual in a study. This data is then combined to model growth over the total age range of all individuals in the study. The limited data collected on each individual precludes a subject-specific ap...
journal_title：Biometrics
pub_type： 杂志文章
doi：
更新日期：1998-06-01 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：:Statistical methods for the detection of genes influencing quantitative traits with the aid of genetic markers are well developed for normally distributed, fully observed phenotypes. Many experiments are concerned with failure-time phenotypes, which have skewed distributions and which are usually subject to censoring ...
journal_title：Biometrics
pub_type： 杂志文章
doi：10.1111/j.1541-0420.2005.00346.x
更新日期：2005-09-01 00:00:00
