Abstract:
:The goal of screening programmes for cancer is early detection and treatment with a consequent reduction in mortality from the disease. Screening programmes need to assess the true benefit of screening, that is, the length of time of extension of survival beyond the time of advancement of diagnosis (lead-time). This paper presents a non-parametric method to estimate the survival function of the post-lead-time survival (or extra survival time) of screen-detected cancer cases based on the observed total life time, namely, the sum of the lead-time and the extra survival time. We apply the method to the well-known data set of the HIP (Health Insurance Plan of Greater New York) breast cancer screening study. We make comparisons with the survival of other groups of cancer cases not detected by screening such as interval cases, cases among individuals who refused screening, and randomized control cases. As compared with Walter and Stitt's model, in which they made parametric assumptions for the extra survival time, our non-parametric method provides a better fit to HIP data in the sense that our estimator for the total survival time has a smaller sum of squares of residuals.
journal_name
Stat Medjournal_title
Statistics in medicineauthors
Xu JL,Prorok PCdoi
10.1002/sim.4780142410subject
Has Abstractpub_date
1995-12-30 00:00:00pages
2715-25issue
24eissn
0277-6715issn
1097-0258journal_volume
14pub_type
杂志文章abstract::Huntington's disease (HD) is a neurodegenerative disorder with a dominant genetic mode of inheritance caused by an expansion of CAG repeats on chromosome 4. Typically, a longer sequence of CAG repeat length is associated with increased risk of experiencing earlier onset of HD. Previous studies of the association betwe...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.5971
更新日期:2014-04-15 00:00:00
abstract::Interval-censored data are commonly found in studies of diseases that progress without symptoms, which require clinical evaluation for detection. Several techniques have been suggested with independent assumption. However, the assumption will not be valid if observations come from clusters. Furthermore, when the clust...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4042
更新日期:2010-12-10 00:00:00
abstract::We construct nonparametric regression estimators of a number of temporal functions in a multistate system based on a continuous univariate baseline covariate. These estimators include state occupation probabilities, state entry, exit, and waiting (sojourn) time distribution functions of a general progressive (e.g., ac...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.5703
更新日期:2013-07-30 00:00:00
abstract::Non-linear mixed-effects models (NLMEMs) are used to improve information gathering from longitudinal studies and are applied to treatment evaluation in disease-evolution studies, such as human immunodeficiency virus (HIV) infection. The estimation of parameters and the statistical tests are critical issues in NLMEMs s...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.2950
更新日期:2007-11-30 00:00:00
abstract::This paper investigates the Bayesian procedures for comparing proportions. These procedures are especially suitable for accepting (or rejecting) the equivalence of two population proportions. Furthermore the Bayesian predictive probabilities provide a natural and flexible tool in monitoring trials, especially for choo...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4780140924
更新日期:1995-05-15 00:00:00
abstract::The generalized estimating equations (GEE) approach is commonly used to model incomplete longitudinal binary data. When drop-outs are missing at random through dependence on observed responses (MAR), GEE may give biased parameter estimates in the model for the marginal means. A weighted estimating equations approach g...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.1241
更新日期:2002-10-30 00:00:00
abstract::Zero-inflated Poisson regression is a popular tool used to analyze data with excessive zeros. Although much work has already been performed to fit zero-inflated data, most models heavily depend on special features of the individual data. To be specific, this means that there is a sizable group of respondents who endor...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.5650
更新日期:2013-04-30 00:00:00
abstract::Reference ranges which take time (such as age) into account are often required in medicine, but simple, systematic and efficient statistical methods for constructing them are lacking. A method is described which is based on low order polynomial curves (linear, quadratic or occasionally cubic), together with guidelines...
journal_title:Statistics in medicine
pub_type: 临床试验,杂志文章,多中心研究
doi:10.1002/sim.4780100502
更新日期:1991-05-01 00:00:00
abstract::This paper introduces a new spatial scan statistic designed to adjust cluster detection for longitudinal confounding factors indexed in space. The functional-model-adjusted statistic was developed using generalized functional linear models in which longitudinal confounding factors were considered to be functional cova...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.8459
更新日期:2020-04-15 00:00:00
abstract::With the increasing availability of detailed clinical information, there is optimism that treatment choices can be selectively directed to those individuals most likely to benefit. While standard clinical trials can establish whether a treatment appears to be effective on average, subsequent work is needed to determin...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.6138
更新日期:2014-07-30 00:00:00
abstract::In survival analyses, inverse-probability-of-treatment (IPT) and inverse-probability-of-censoring (IPC) weighted estimators of parameters in marginal structural Cox models are often used to estimate treatment effects in the presence of time-dependent confounding and censoring. In most applications, a robust variance e...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.7823
更新日期:2018-10-30 00:00:00
abstract::A measure of similarity for response curves is presented and its potential use is discussed. The distribution of a suitable test statistic for testing the independence of the course of two curves is derived. The method proposed is compared with other proposals in the literature for the analysis of paired response curv...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4780081112
更新日期:1989-11-01 00:00:00
abstract::In this paper we give an informal introduction to a robust method for survival analysis which is based on a modification of the usual partial likelihood estimator (PLE). Large sample results lead us to expect reduced bias for this robust estimator compared with the PLE whenever there are even slight violations of the ...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/(SICI)1097-0258(19960530)15:10<1033::AID-S
更新日期:1996-05-30 00:00:00
abstract::Subjective judgements of complex variables are commonly recorded as ordered categorical data. The rank-invariant properties of such data are well known, and there are various statistical approaches to the analysis and modelling of ordinal data. This paper focuses on the non-additive property of ordered categorical dat...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/(sici)1097-0258(19981230)17:24<2923::aid-s
更新日期:1998-12-30 00:00:00
abstract::It is valuable in many studies to assess both intrarater and interrater agreement. Most measures of intrarater agreement do not adjust for unequal estimates of prevalence between the separate rating occasions for a given rater and measures of interrater agreement typically ignore data from the second set of assessment...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.1138
更新日期:2002-06-30 00:00:00
abstract::In this paper we examine the efficiency of a generalization of the traditional normal linear (LDA) or quadratic (QDA) discriminant analysis. This procedure (the generalized discriminant analysis, GDA) replaces each normal density used in the traditional classification rule by a Fourier series density estimator which '...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4780100319
更新日期:1991-03-01 00:00:00
abstract::Identification of the latency period for the effect of a time-varying exposure is key when assessing many environmental, nutritional, and behavioral risk factors. A pre-specified exposure metric involving an unknown latency parameter is often used in the statistical model for the exposure-disease relationship. Likelih...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.8038
更新日期:2019-03-30 00:00:00
abstract::A new goodness-of-fit test for the logistic regression model is proposed. It exploits the property of this model that when it is correct, i.e. not misspecified, the parameter estimates are (asymptotically) invariant under reweighting the observations by weights wi that are a function of the binary (0/1) outcomes yi. M...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.1997
更新日期:2005-01-15 00:00:00
abstract::We describe the usual statistical concepts and consequent appropriate simulations of a prospective study for the simple case of a single risk variable and an assumed logistic model. We examine the simulations of Lilienfeld and Pyne, and show that they are seriously flawed. Contrary to those authors' claims, the estima...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4780040212
更新日期:1985-04-01 00:00:00
abstract::It is not uncommon for a continuous outcome variable Y to be dichotomized and analysed using logistic regression. Moser and Coombs (Statist. Med. 2004; 23:1843-1860) provide a method for converting the output from a standard linear regression analysis using the original continuous outcome Y to give much more efficient...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.3474
更新日期:2009-01-30 00:00:00
abstract::Regardless of whether a statistician believes in letting a data set speak for itself through nominal p-values or believes in strict alpha conservation, the interpretation of experiments which are negative for the primary endpoint but positive for secondary endpoints is the source of some angst. The purpose of this pap...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/(sici)1097-0258(20000330)19:6<767::aid-sim
更新日期:2000-03-30 00:00:00
abstract::The Rvachev-Baroyan-Longini model is a space-time predictive model of the spread of influenza epidemics. It has been applied to 128 cities of the USSR, and more recently, to forecasting the spread of the pandemic of 1968-1969 throughout 52 large cities. It is a deterministic, mass-action, space and time continuous mod...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4780071107
更新日期:1988-11-01 00:00:00
abstract::Nutritional exposures are often measured with considerable error in commonly used surrogate instruments such as the food frequency questionnaire (FFQ) (denoted by Q(i) for the ith subject). The error can be both systematic and random. The diet record (DR) denoted by R(i) for the ith subject is considered an alloyed go...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.3238
更新日期:2008-08-15 00:00:00
abstract::Many complex diseases are known to be affected by the interactions between genetic variants and environmental exposures beyond the main genetic and environmental effects. Study of gene-environment (G×E) interactions is important for elucidating the disease etiology. Existing Bayesian methods for G×E interaction studie...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.8434
更新日期:2020-02-28 00:00:00
abstract::Orthogonal polynomial scores (OPS) is a simple, biologically meaningful approach to characterize longitudinal data in phase I and II clinical pharmacology trials. It describes average, linear, quadratic and higher order polynomial characteristics of each subject's response over time with use of composite scores comput...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4780120703
更新日期:1993-04-15 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::Meta-analyses of clinical trials are increasingly seeking to go beyond estimating the effect of a treatment and may also aim to investigate the effect of other covariates and how they alter treatment effectiveness. This requires the estimation of treatment-covariate interactions. Meta-regression can be used to estimat...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.2768
更新日期:2007-07-10 00:00:00
abstract::In this paper, we consider fitting a flexible and interpretable additive regression model in a data-rich setting. We wish to avoid pre-specifying the functional form of the conditional association between each covariate and the response, while still retaining interpretability of the fitted functions. A number of recen...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.7859
更新日期:2019-02-20 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::In this paper the following problem of clinical research is explored. Several potential new treatments are available for use against a certain disease. These are evaluated in a series of pilot studies which will constitute phase II clinical trials. The most promising will then be compared with a standard treatment in ...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4780050510
更新日期:1986-09-01 00:00:00