Inference for multimarker adaptive enrichment trials.

abstract：:Multivariate finite mixture models have been applied to the identification of dietary patterns. These models are known to have many parameters, and consequently large samples are usually required. We present a special case of a multivariate mixture model that reduces the number of parameters to be estimated and seems ...

journal_title：Statistics in medicine

authors： Rita Gaio A,Costa JP,Santos AC,Ramos E,Lopes C

更新日期：2012-08-30 00:00:00

abstract：:For robust detection performance, traditional control chart monitoring for biosurveillance is based on input data free of trends, day-of-week effects, and other systematic behaviour. Time series forecasting methods may be used to remove this behaviour by subtracting forecasts from observations to form residuals for al...

journal_title：Statistics in medicine

authors： Burkom HS,Murphy SP,Shmueli G

更新日期：2007-09-30 00:00:00

abstract：:Random forest is a supervised learning method that combines many classification or regression trees for prediction. Here we describe an extension of the random forest method for building event risk prediction models in survival analysis with competing risks. In case of right-censored data, the event status at the pred...

journal_title：Statistics in medicine

authors： Mogensen UB,Gerds TA

更新日期：2013-08-15 00:00:00

abstract：:In different fields of applications including, but not limited to, behavioral, environmental, medical sciences, and econometrics, the use of panel data regression models has become increasingly popular as a general framework for making meaningful statistical inferences. However, when the ordinary least squares (OLS) m...

journal_title：Statistics in medicine

authors： Hamiye Beyaztas B,Bandyopadhyay S

更新日期：2020-12-20 00:00:00

abstract：:Many studies have reported large variations in age- and sex-adjusted rates of hospitalizations across small geographic areas. These variations have often been attributed to differences in medical practice style which are not reflected in differences in health care outcomes. There is, however, another potentially impor...

journal_title：Statistics in medicine

authors： Peköz EA,Shwartz M,Iezzoni LI,Ash AS,Posner MA,Restuccia JD

更新日期：2003-05-30 00:00:00

abstract：:Unmeasured confounding is a common concern when researchers attempt to estimate a treatment effect using observational data or randomized studies with nonperfect compliance. To address this concern, instrumental variable methods, such as 2-stage predictor substitution (2SPS) and 2-stage residual inclusion (2SRI), have...

journal_title：Statistics in medicine

authors： Wan F,Small D,Mitra N

更新日期：2018-05-30 00:00:00

abstract：:Binary classification rules based on covariates typically depend on simple loss functions such as zero-one misclassification. Some cases may require more complex loss functions. For example, individual-level monitoring of HIV-infected individuals on antiretroviral therapy requires periodic assessment of treatment fail...

journal_title：Statistics in medicine

authors： Xu Y,Liu T,Daniels MJ,Kantor R,Mwangi A,Hogan JW

更新日期：2019-05-20 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

authors： Ghosh P,Rosner GL

更新日期：2007-03-15 00:00:00

abstract：:We present an estimate of the kappa-coefficient of agreement between two methods of rating based on matched pairs of binary responses and show that the estimate depends on the common intraclass correlation coefficient between the pairs. Via Monte Carlo simulation, we investigate power of the test of significance on ka...

journal_title：Statistics in medicine

authors： Shoukri MM,Martin SW,Mian IU

更新日期：1995-01-15 00:00:00

abstract：:Differences between arm-based (AB) and contrast-based (CB) models for network meta-analysis (NMA) are controversial. We compare the CB model of Lu and Ades (2006), the AB model of Hong et al(2016), and two intermediate models, using hypothetical data and a selected real data set. Differences between models arise prima...

journal_title：Statistics in medicine

authors： White IR,Turner RM,Karahalios A,Salanti G

更新日期：2019-11-30 00:00:00

abstract：:Many randomized clinical trials include a data and safety monitoring board (DSMB) that is responsible for reviewing accruing data, monitoring performance of the trial, assuring safety of the participants in the trial, and assessing the efficacy of treatment. The DSMB often makes recommendations about continuation of t...

journal_title：Statistics in medicine

authors： Wittes J

更新日期：1993-03-01 00:00:00

abstract：:There are many settings in which the distribution of error in a mismeasured covariate varies with the value of another covariate. Take, for example, the case of HIV phylogenetic cluster size, large values of which are an indication of rapid HIV transmission. Researchers wish to find behavioral correlates of HIV phylog...

journal_title：Statistics in medicine

authors： Parveen N,Moodie E,Brenner B

更新日期：2017-07-30 00:00:00

abstract：:To study the effect of a mega hydropower dam in southwest Ethiopia on malaria incidence, we have set up a longitudinal study. To gain insight in temporal and spatial aspects, that is, in time (period  =  year-season combination) and location (village), we need models that account for these effects. The frailty model w...

journal_title：Statistics in medicine

authors： Getachew Y,Janssen P,Yewhalaw D,Speybroeck N,Duchateau L

更新日期：2013-08-15 00:00:00

abstract：:We extend the shared frailty model of recurrent events and a dependent terminal event to allow for a nonparametric covariate function. We include a Gaussian random effect (frailty) in the intensity functions of both the recurrent and terminal events to capture correlation between the two processes. We employ the penal...

journal_title：Statistics in medicine

authors： Zhangsheng Y,Liu L

更新日期：2011-09-30 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：:Estimates of relative efficacy between alternative treatments are crucial for decision making in health care. Bayesian mixed treatment comparison models provide a powerful methodology to obtain such estimates when head-to-head evidence is not available or insufficient. In recent years, this methodology has become wide...

journal_title：Statistics in medicine

authors： Schmitz S,Adams R,Walsh C

更新日期：2013-07-30 00:00:00

abstract：:Austin Bradford Hill was once a friend to The Lancet, but, as occasionally happens, friends fall out. The great legacy of his association with the journal, however, was Principles of Medical Statistics. As each edition was succeeded by another--the first in 1937, the last in 1991--he seemed to shift his view about the...

journal_title：Statistics in medicine

authors： Horton R

更新日期：2000-12-15 00:00:00

abstract：:We investigated interobserver variation between three physician readers in the independent classification of chest radiographs from 1771 taconite workers for pneumoconiosis. We analysed variation with a general methodology for the analysis of categorical data, and quantified interobserver agreement in terms of kappa-t...

journal_title：Statistics in medicine

authors： Musch DC,Landis JR,Higgins IT,Gilson JC,Jones RN

更新日期：1984-01-01 00:00:00

abstract：:In this paper we present a simple method for constructing (1- alpha)100 per cent confidence intervals for binomial proportions with near nominal coverage for all underlying proportion parameters on the unit interval. This new method uses, with a slight modification, the standard normal approximation technique taught i...

journal_title：Statistics in medicine

authors： Borkowf CB

更新日期：2006-11-15 00:00:00

abstract：:A technique is presented which provides guidance on the spacing of follow-up waves in a multiwave study. Only information from the baseline wave is needed, as well as rough parameter estimates for the survival distribution. The computations use the expected Fisher information; a new method for its calculation is given...

journal_title：Statistics in medicine

authors： Chappell R

更新日期：1991-12-01 00:00:00

abstract：:Both traditional phase I designs and the increasingly popular continual reassessment method (CRM) designs select an estimate of maximum tolerable dose (MTD) from among a set of prespecified dose levels. Although CRM designs use an implied dose-response model to select the next dose level, in general it is neither assu...

journal_title：Statistics in medicine

authors： Storer BE

更新日期：2001-08-30 00:00:00

abstract：:Hierarchical regression analysis holds much promise for epidemiologic analysis, but has as yet seen limited application because of lack of easily used software and the relatively lengthy run times of preferred fitting methods (such as true maximum likelihood and Bayesian approaches). This paper compares three relative...

journal_title：Statistics in medicine

authors： Greenland S

更新日期：1997-03-15 00:00:00

abstract：:The lifetime risk of a clinical condition is the probability of onset of the condition during one's lifespan. Recent advances in Alzheimer's disease (AD) research have identified screening tests for biomarkers that can identify persons who are in the earliest stages of the AD process but who do not yet have any clinic...

journal_title：Statistics in medicine

authors： Brookmeyer R,Abdalla N

更新日期：2019-04-30 00:00:00

abstract：:Graphical methods are often used to check goodness-of-fit of models to data. It is common to plot residuals against a reference distribution so that when the model fits the data, the configuration should be close to a straight line. Since the resemblance to a straight line is often unclear, it has been suggested to ad...

journal_title：Statistics in medicine

authors： Cohen A,Barnett O

更新日期：1995-08-30 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

authors： Lester Kirchner H,Lemke JH

更新日期：2002-06-30 00:00:00

abstract：:Suppose that two graders classify all eyes in a sample of patients for the presence or absence of a specified abnormality. In the statistical analysis of the data, possible correlation between the observations in the right and left eyes should be taken into account. Recently, general methods have been developed to ana...

journal_title：Statistics in medicine

authors： Schouten HJ

更新日期：1993-12-15 00:00:00

abstract：:Detecting safety signals in clinical trial safety data is known to be challenging due to high dimensionality, rare occurrence, weak signal, and complex dependence. We propose a new hierarchical testing approach for analyzing safety data from a typical randomized clinical trial. This approach accounts for the hierarchi...

journal_title：Statistics in medicine

authors： Tan X,Chen BE,Sun J,Patel T,Ibrahim JG

更新日期：2020-05-15 00:00:00

abstract：:During a course of human immunodeficiency virus (HIV-1) infection, the viral load usually increases sharply to a peak following infection and then drops rapidly to a steady state, where it remains until progression to AIDS. This steady state is often referred to as the viral set point. It is believed that the HIV vira...

journal_title：Statistics in medicine

authors： Mei Y,Wang L,Holte SE

更新日期：2008-01-15 00:00:00

abstract：:A calibration line is used to define the relationship between a new clinical technique and a standard in vitro laboratory methodology. Discrimination intervals quantify the reliability of inverse estimates obtained from the calibration line. Applied to transcutaneous PCO2 monitoring, a new in vivo measurement, discrim...

journal_title：Statistics in medicine

authors： Kost GJ

更新日期：1986-07-01 00:00:00

abstract：:This paper reviews several emerging and recurrent issues relating to the drug development process. These emerging issues include changes to the FDA regulatory environment, internationalization of drug development, advances in computer technology and visualization tools, and efforts to incorporate meta-analysis methodo...

journal_title：Statistics in medicine

authors： Anello C

更新日期：1999-09-15 00:00:00