Abstract:
:In a medical study we are often interested in graphically displaying the relationship between continuous variables and clinical events indicating disease progression. Often, it is reasonable to make the minimal assumption that the risk of progression is an arbitrary monotone function of the continuous variable. Sometimes the continuous variable is a disease marker which is recorded longitudinally, and so the goal is to provide a graphical display of the relationship between the hazard for progression and the most recent measurement of the longitudinal marker. For example, we know that for a patient with HIV infection, declining CD4 count is associated with an increased risk of opportunistic infection. The goal of this paper is to extend isotonic regression techniques to failure time data with a continuous covariate, to obtain a non-parametric estimate for the hazard of disease progression as a monotonic function of the continuous variable. We propose two methods for modelling the relationship of the hazard and covariate: the first assumes that the hazard is constant over time, and the second allows the hazard to be an arbitrary function of time. These methods will be applied to graphically display the risk for an AIDS patient of an opportunistic infection as a function of CD4 count.
journal_name
Stat Medjournal_title
Statistics in medicineauthors
Ancukiewicz M,Finkelstein DM,Schoenfeld DAdoi
10.1002/sim.1561subject
Has Abstractpub_date
2003-10-30 00:00:00pages
3151-9issue
20eissn
0277-6715issn
1097-0258journal_volume
22pub_type
杂志文章abstract::The purpose of this research was to develop appropriate methods for analysing repeated ordinal categorical data that arose in an intervention trial to prevent oesophageal cancer. The measured response was the degree of oesophageal dysplasia at 2.5 and 6 years after randomization. An important feature was that some res...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4780130511
更新日期:1994-03-15 00:00:00
abstract::The one-step (Peto) method for obtaining pooled effect estimates can yield extremely biased results when applied to unbalanced data. Even for balanced studies, the one-step estimate may incorporate an unacceptable degree of bias. In place of the one-step estimate, we recommend use of ordinary Mantel-Haenszel, weighted...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4780090307
更新日期:1990-03-01 00:00:00
abstract::Researchers in clinical science and bioinformatics frequently aim to learn which of a set of candidate biomarkers is important in determining a given outcome, and to rank the contributions of the candidates accordingly. This article introduces a new approach to research questions of this type, based on targeted maximu...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.3414
更新日期:2009-01-15 00:00:00
abstract::The power prior has been widely used in many applications covering a large number of disciplines. The power prior is intended to be an informative prior constructed from historical data. It has been used in clinical trials, genetics, health care, psychology, environmental health, engineering, economics, and business. ...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.6728
更新日期:2015-12-10 00:00:00
abstract::Motivated by a study for soft tissue sarcoma, this article considers the analysis of diseases recurrence and survival. A multivariate frailty hazard model is established for joint modeling of three correlated time-to-event outcomes: local disease recurrence, distant disease recurrence (metastasis), and death. The goal...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.7030
更新日期:2016-11-20 00:00:00
abstract::We consider the design of both cohort and case-control studies in which an initial ('stage 1') sample of complete data on an error-free disease indicator (D), a correct ('gold standard') dichotomous exposure measurement (X) and an error-prone exposure measurement (Z) are available. We calculate the amount of additiona...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4780142307
更新日期:1995-12-15 00:00:00
abstract::Composite endpoints are frequently used in clinical trials, but simple approaches, such as the time to first event, do not reflect any ordering among the endpoints. However, some endpoints, such as mortality, are worse than others. A variety of procedures have been proposed to reflect the severity of the individual en...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.8431
更新日期:2020-02-28 00:00:00
abstract::This work is motivated by a longitudinal study of women and their ectopic pregnancy outcomes in Lund, Sweden. In this article, we review and apply the Liang-Zeger methodology to the Lund ectopic pregnancy data set. We further analyse the ectopic pregnancy data using conditional modelling approaches suggested by Rosner...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/(sici)1097-0258(19971115)16:21<2403::aid-s
更新日期:1997-11-15 00:00:00
abstract::For each of 211 arteriosclerosis obliterans patients, the degree of stenosis of arteries at four sites were examined at Hiroshima University Hospital to analyse the relationship between the degree of stenosis and age, sex and site. The generalized estimating equations using a proportional odds model for the stenosis p...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.1363
更新日期:2003-07-15 00:00:00
abstract::We consider the problem of comparing cumulative incidence functions of non-mortality events in the presence of informative coarsening and the competing risk of death. We extend frequentist-based hypothesis tests previously developed for non-informative coarsening and propose a novel Bayesian method based on comparing ...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.3397
更新日期:2008-12-10 00:00:00
abstract::Biomarkers that predict the efficacy of treatment can potentially improve clinical outcomes and decrease medical costs by allowing treatment to be provided only to those most likely to benefit. We consider the design of a randomized clinical trial in which one objective is to evaluate a treatment selection marker. The...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.6564
更新日期:2015-11-30 00:00:00
abstract::Epidemiologic and clinical studies routinely collect longitudinal measures of multiple outcomes, including biomarker measures, cognitive functions, and clinical symptoms. These longitudinal outcomes can be used to establish the temporal order of relevant biological processes and their association with the onset of cli...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.5557
更新日期:2013-03-15 00:00:00
abstract::When data are dichotomous, this paper notes the utility of inverse sampling in establishing equivalence with respect to the risk ratio. This paper develops an exact equivalence test that accounts for the risk ratio under inverse sampling and further discusses the relationship between the exact equivalence test and the...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/(sici)1097-0258(19970815)16:15<1777::aid-s
更新日期:1997-08-15 00:00:00
abstract::Health questionnaires are often built up from sets of questions that are totaled to obtain a sum score. An important consideration in designing questionnaires is to minimize respondent burden. An increasingly popular method for efficient measurement is computerized adaptive testing; unfortunately, many health question...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.5936
更新日期:2014-02-10 00:00:00
abstract::Much has been published on various aspects of data analysis and reporting from clinical trials within the biopharmaceutical environment. This ranges from regulatory guidelines on the format and content of registration dossiers to recommendations on data presentation and the statistical methodologies that are appropria...
journal_title:Statistics in medicine
pub_type: 杂志文章,评审
doi:10.1002/(sici)1097-0258(19980815/30)17:15/16<1829:
更新日期:1998-08-15 00:00:00
abstract::I derive the locally most powerful rank tests for acceleration against semi-parametric alternatives when some patients are cured of the disease. I consider some particular classes of alternatives and present simulation results to verify the validity of the proposed tests. Real data from clinical trials for childhood l...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4780141905
更新日期:1995-10-15 00:00:00
abstract::Population dynamic models, commonly used tools in the study of epidemics and other complex population processes, are implicit non-linear mathematical equations. Inference based on such models can be difficult due to the problems associated with high dimensional parameters that may be non-identified and complex likelih...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.1258
更新日期:2002-12-15 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::In failure time studies involving a chronic disease such as cancer, several competing causes of mortality may be operating. Commonly, the conventional statistical technique of Kaplan-Meier, which is only meaningfully interpreted by assuming independence of failure types and the censoring mechanism, is employed in clin...
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/sim.711
更新日期:2001-03-15 00:00:00
abstract::We examine Goodman and Kruskal's lambda using Efron's approach to regression and analysis of variance (ANOVA) for zero-one outcome data. For a binary response cross-classified by a single nominal predictor, we present a computationally simple ANOVA table in which lambda is analogous to Pearson's R-square. We character...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4780080511
更新日期:1989-05-01 00:00:00
abstract::A study of long term survival of 1487 patients given an allogeneic bone marrow transplant for acute myelogenous leukaemia and 729 patients given a transplant for severe aplastic anaemia was conducted by the International Bone Marrow Transplant Registry. One aim of this study is to determine if the mortality rates of t...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/(sici)1097-0258(19990630)18:12<1529::aid-s
更新日期:1999-06-30 00:00:00
abstract::Current methods for statistical analysis of twin studies focus on continuous and dichotomous data, while only limited methodology exists for analysing multinomial data. As a consequence, investigators are often tempted to collapse multinomial data into two categories simply to facilitate the analysis. We address this ...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/1097-0258(20010130)20:2<249::aid-sim641>3.
更新日期:2001-01-30 00:00:00
abstract::The cost and efficiency of training clinical centre staff and of duplicate data entry in clinical trials is reviewed. Training is an essential component of quality assurance programmes and it is usually carried out at regular intervals in long-term clinical trials. Initial training of staff and regular retraining is i...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4780090118
更新日期:1990-01-01 00:00:00
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 p...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4780142410
更新日期:1995-12-30 00:00:00
abstract::To summarize safety data such as clinical adverse experiences in clinical trials with a moderate to long-term follow-up, we may use a measurement which accounts for the potential differences in the follow-up duration between treatment groups. The incidence rate, which uses the total person-time follow-up in a treatmen...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.2335
更新日期:2006-04-30 00:00:00
abstract::Bioequivalence assessment is an issue of great interest. Development of statistical methods for assessing bioequivalence is an important area of research for statisticians. Bioequivalence is usually determined based on the normal distribution. We relax this assumption and develop a semi-parametric mixed model for bioe...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.2620
更新日期:2007-03-15 00:00:00
abstract::This paper presents a general approach for simultaneously assessing, from serial data, diagnostic consistency, interrater reliability and incidence of a strictly progressive disease. Observed data are viewed as incomplete: diagnostic errors are not distinguished from true diagnoses. We introduce a broad class of model...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4780070306
更新日期:1988-03-01 00:00:00
abstract::Prevalent sampling is frequently a convenient and economical sampling technique for the collection of time-to-event data and thus is commonly used in studies of the natural history of a disease. However, it is biased by design because it tends to recruit individuals with longer survival times. This paper considers est...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.7184
更新日期:2017-04-15 00:00:00
abstract::This paper describes the Stoke Index which has been designed to give a global measure of disease activity in rheumatoid arthritis. The index is based on two objective laboratory measurements, one subjective and two semi-objective clinical measurements, chosen from 13 measurements using clinical judgement. Variable sel...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.4780121206
更新日期:1993-06-30 00:00:00
abstract::Although transportation safety has greatly improved over the past 2 decades, motor vehicle crash injuries remain a leading cause of morbidity and mortality, particularly among young drivers. Driver errors and behaviors such as speeding and distraction contribute disproportionately to crashes among inexperienced novice...
journal_title:Statistics in medicine
pub_type: 杂志文章
doi:10.1002/sim.7404
更新日期:2017-10-30 00:00:00