Accounting for informatively missing data in logistic regression by means of reassessment sampling.

abstract：:Performance of a diagnostic test is ideally evaluated by a comparison of the test results to a gold standard for all the patients in a study. In practice, however, it is common for a subset of study patients to have the gold standard not verified (missing) due to ethical or expense considerations. Sensitivity and spec...

journal_title：Statistics in medicine

authors： Kosinski AS,Chen Y,Lyles RH

更新日期：2010-07-10 00:00:00

abstract：:It is naive and incorrect to use the proportions of successful operations to compare the performance of surgeons because the patients' risk profiles are different. In this paper, we explore the use of risk-adjusted procedures to compare the performance of surgeons. One such risk-adjusted statistic is the standardized ...

journal_title：Statistics in medicine

authors： Tang X,Gan FF

更新日期：2017-07-20 00:00:00

abstract：:Genetic networks for gene expression data are often built by graphical models, which in turn are built from pair-wise correlations of gene expression levels. A key feature of building graphical models is the evaluation of conditional independence of two traits, given other traits. When conditional independence can be ...

journal_title：Statistics in medicine

authors： Yu Z,Wang L,Hildebrandt MA,Schaid DJ

更新日期：2008-08-30 00:00:00

abstract：:Selection of dose for cancer patients treated with radiation therapy (RT) must balance the increased efficacy with the increased toxicity associated with higher dose. Historically, a single dose has been selected for a population of patients (e.g., all stage III non-small cell lung cancer). However, the availability o...

journal_title：Statistics in medicine

authors： Schipper MJ,Taylor JM,TenHaken R,Matuzak MM,Kong FM,Lawrence TS

更新日期：2014-12-30 00:00:00

abstract：:When a cancer patient develops a new tumor it is necessary to determine if it is a recurrence (metastasis) of the original cancer, or an entirely new occurrence of the disease. This is accomplished by assessing the histo-pathology of the lesions. However, there are many clinical scenarios in which this pathological di...

journal_title：Statistics in medicine

authors： Ostrovnaya I,Olshen AB,Seshan VE,Orlow I,Albertson DG,Begg CB

更新日期：2010-07-10 00:00:00

abstract：:Multivariate random length data occur when we observe multiple measurements of a quantitative variable and the variable number of these measurements is also an observed outcome for each experimental unit. For example, for a patient with coronary artery disease, we may observe a number of lesions in that patient's coro...

journal_title：Statistics in medicine

authors： Barnhart HX,Kosinski AS,Sampson AR

更新日期：1999-01-30 00:00:00

abstract：:The design of clinical trials often requires knowledge of quantities such as between- and within subject variances about which only imprecise information exists. To provide assurance that the study has the desired power to detect a minimum clinically meaningful difference between treatment groups. Gould, Gould and Shi...

journal_title：Statistics in medicine

authors： Shih WJ,Gould AL

更新日期：1995-10-30 00:00:00

abstract：:Slow recruitment in clinical trials leads to increased costs and resource utilization, which includes both the clinic staff and patient volunteers. Careful planning and monitoring of the accrual process can prevent the unnecessary loss of these resources. We propose two hierarchical extensions to the existing Bayesian...

journal_title：Statistics in medicine

authors： Jiang Y,Simon S,Mayo MS,Gajewski BJ

更新日期：2015-02-20 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

authors： Enders D,Engel S,Linder R,Pigeot I

更新日期：2018-10-30 00:00:00

abstract：:Quality of life (QOL) assessment is a key component of many clinical studies and frequently requires the use of single global summary measures that capture the overall balance of findings from a potentially wide-ranging assessment of QOL issues. We propose and evaluate an irregular multilevel latent variable model sui...

journal_title：Statistics in medicine

authors： Kifley A,Heller GZ,Beath KJ,Bulger D,Ma J,Gebski V

更新日期：2012-05-20 00:00:00

abstract：:Longitudinal studies with repeated measures are often subject to non-response. Methods currently employed to alleviate the difficulties caused by missing data are typically unsatisfactory, especially when the cause of the missingness is related to the outcomes. We present an approach for incomplete categorical data in...

journal_title：Statistics in medicine

authors： West CP,Dawson JD

更新日期：2002-01-30 00:00:00

abstract：:Bioequivalence or interaction trials are commonly studied in crossover design and can be analysed by nonlinear mixed effects models as an alternative to noncompartmental approach. We propose an extension of the population Fisher information matrix in nonlinear mixed effects models to design crossover pharmacokinetic t...

journal_title：Statistics in medicine

authors： Nguyen TT,Bazzoli C,Mentré F

更新日期：2012-05-20 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

authors： Moyé LA

更新日期：2000-03-30 00:00:00

abstract：:Binary matched-pairs data occur commonly in longitudinal studies, such as in cross-over experiments. Many analyses for comparing the matched probabilities of a particular outcome do not utilize pairs having the same outcome for each observation. An example is McNemar's test. Some methodologists find this to be counter...

journal_title：Statistics in medicine

authors： Agresti A,Min Y

更新日期：2004-01-15 00:00:00

abstract：:Repeated cross-sectional samples are common in national surveys of health like the National Health Interview Survey (NHIS). Because population health outcomes generally evolve slowly, pooling data across years can improve the precision of current-year annual estimates of disease prevalence and other health outcomes. P...

journal_title：Statistics in medicine

authors： Lockwood JR,McCaffrey DF,Setodji CM,Elliott MN

更新日期：2011-02-28 00:00:00

abstract：:In psychiatry, clinicians use criteria sets from the Diagnostic and Statistical Manual of Mental Disorders to diagnose mental disorders. Most criteria sets have several symptom domains, and in order to be diagnosed, an individual must meet the minimum number of symptoms required by each domain. Some efforts are now fo...

journal_title：Statistics in medicine

authors： Mauro C,Shear MK,Wang Y

更新日期：2019-07-20 00:00:00

abstract：:In behavioral, biomedical, and social-psychological sciences, it is common to encounter latent variables and heterogeneous data. Mixture structural equation models (SEMs) are very useful methods to analyze these kinds of data. Moreover, the presence of missing data, including both missing responses and missing covaria...

journal_title：Statistics in medicine

authors： Cai JH,Song XY,Hser YI

更新日期：2010-08-15 00:00:00

abstract：:The most popular model used for survival analysis is the proportional hazards regression model proposed by Cox. This is mainly due to its exceptional simplicity. Nevertheless the fundamental assumption of the Cox model is the proportionality of the hazards. For many applications, however, this assumption is doubtful. ...

journal_title：Statistics in medicine

authors： Berger U,Schäfer J,Ulm K

更新日期：2003-04-15 00:00:00

abstract：:Relative survival provides a measure of the proportion of patients dying from the disease under study without requiring the knowledge of the cause of death. We propose an overall strategy based on regression models to estimate the relative survival and model the effects of potential prognostic factors. The baseline ha...

journal_title：Statistics in medicine

authors： Remontet L,Bossard N,Belot A,Estève J,French network of cancer registries FRANCIM.

更新日期：2007-05-10 00:00:00

abstract：:The primary purpose of a disease surveillance system is to provide data for the detection of changes in the incidence of the disease. Methods for the analysis of data from surveillance systems are reviewed. A new procedure is proposed for use when the system includes geographically dispersed reporting units, such as h...

journal_title：Statistics in medicine

authors： Raubertas RF

更新日期：1989-03-01 00:00:00

abstract：:Multivariate outcomes measured longitudinally over time are common in medicine, public health, psychology and sociology. The typical (saturated) longitudinal multivariate regression model has a separate set of regression coefficients for each outcome. However, multivariate outcomes are often quite similar and many out...

journal_title：Statistics in medicine

authors： Jia J,Weiss RE

更新日期：2009-06-15 00:00:00

abstract：:Sample size planning should reflect the primary objective of a trial. If the primary objective is prediction, the sample size determination should focus on prediction accuracy instead of power. We present formulas for the determination of training set sample size for survival prediction. Sample size is chosen to contr...

journal_title：Statistics in medicine

authors： Götte H,Zwiener I

更新日期：2013-02-28 00:00:00

abstract：:It has been well known that ignoring measurement error may result in substantially biased estimates in many contexts including linear and nonlinear regressions. For survival data with measurement error in covariates there has been extensive discussion in the literature with the focus being on the Cox proportional haza...

journal_title：Statistics in medicine

authors： He W,Yi GY,Xiong J

更新日期：2007-11-20 00:00:00

abstract：:Few methods are currently available for group sequential analysis of recurrent events data subject to a terminal event in the clinical trial setting. This research helps fill this gap by developing a completely nonparametric group sequential monitoring procedure for use with the two-sample Tayob and Murray statistic. ...

journal_title：Statistics in medicine

authors： Xia M,Murray S,Tayob N

更新日期：2019-12-30 00:00:00

abstract：:The receiver operating characteristic (ROC) curve is a popular technique with applications, for example, investigating an accuracy of a biomarker to delineate between disease and non-disease groups. A common measure of accuracy of a given diagnostic marker is the area under the ROC curve (AUC). In contrast with the AU...

journal_title：Statistics in medicine

authors： Yu J,Yang L,Vexler A,Hutson AD

更新日期：2016-06-15 00:00:00

abstract：:We develop reinforcement learning trials for discovering individualized treatment regimens for life-threatening diseases such as cancer. A temporal-difference learning method called Q-learning is utilized that involves learning an optimal policy from a single training set of finite longitudinal patient trajectories. A...

journal_title：Statistics in medicine

authors： Zhao Y,Kosorok MR,Zeng D

更新日期：2009-11-20 00:00:00

abstract：:The sojourn time, time spent in the preclinical detectable phase (PCDP) for chronic diseases, for example, breast cancer, plays an important role in the design and assessment of screening programmes. Traditional methods to estimate it usually assume a uniform incidence rate of preclinical disease from a randomized con...

journal_title：Statistics in medicine

authors： Duffy SW,Chen HH,Tabar L,Day NE

更新日期：1995-07-30 00:00:00

abstract：:We simulated multinomial AIDS incidence counts from 27 'representative' AIDS epidemics that spanned a period corresponding to previous applications of backcalculation (1 January 1977 to 1 July 1987) and assessed mean square error for several back-calculated estimators of HIV prevalence and short-term AIDS projections....

journal_title：Statistics in medicine

authors： Rosenberg PS,Gail MH,Pee D

更新日期：1991-08-01 00:00:00

abstract：:Crossover studies have been successfully conducted in the case of continuous responses. Existing procedures of analysis for ordinal responses, on the other hand, are rarely satisfactory unless strict, usually unrealistic, assumptions are made. In this paper we investigate a random effects model and show that the model...

journal_title：Statistics in medicine

authors： Ezzet F,Whitehead J

更新日期：1991-06-01 00:00:00

abstract：:Assessing and comparing the performance of correlated predictive scores are of current interest in precision medicine. Given the limitations of available theoretical approaches for assessing and comparing the predictive accuracy, numerical methods are highly desired which, however, have not been systematically develop...

journal_title：Statistics in medicine

authors： Zhang Y,Shao Y

更新日期：2020-09-10 00:00:00