Confidence intervals for the standardized effect arising in the comparison of two normal populations.

abstract：:We consider the estimation of parameters in a particular segmented generalized linear model with additive measurement error in predictors, with a focus on linear and logistic regression. In epidemiologic studies segmented regression models often occur as threshold models, where it is assumed that the exposure has no i...

journal_title：Statistics in medicine

authors： Küchenhoff H,Carroll RJ

更新日期：1997-01-15 00:00:00

abstract：:Estimates of analyte concentrations, obtained by immunoassay, have error distributions which are generally underestimated. Better estimates, which take into account the distribution of the response metameter of the calibration curve and uncertainties associated with the location of the fitted curve, have been obtained...

journal_title：Statistics in medicine

authors： Kay C,Nix AB,Kemp KW,Rowlands RJ,Richards G,Groom GV,Griffiths K,Wilson DW

更新日期：1986-03-01 00:00:00

abstract：:The objective of this report is to provide a basis to inform decisions about priorities for developing statistical research initiatives in the field of public health surveillance for emerging threats. Rapid information system advances have created a vast opportunity of secondary data sources for information to enhance...

journal_title：Statistics in medicine

authors： Rolka H,Burkom H,Cooper GF,Kulldorff M,Madigan D,Wong WK

更新日期：2007-04-15 00:00:00

abstract：:We consider using observational data to estimate the effect of a treatment on disease recurrence, when the decision to initiate treatment is based on longitudinal factors associated with the risk of recurrence. The effect of salvage androgen deprivation therapy (SADT) on the risk of recurrence of prostate cancer is in...

journal_title：Statistics in medicine

authors： Kennedy EH,Taylor JM,Schaubel DE,Williams S

更新日期：2010-11-10 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

authors： Li S

更新日期：2017-04-15 00:00:00

abstract：:A mixture model incorporating long-term survivors has been adopted in the field of biostatistics where some individuals may never experience the failure event under study. The surviving fractions may be considered as cured. In most applications, the survival times are assumed to be independent. However, when the survi...

journal_title：Statistics in medicine

authors： Yau KK,Ng AS

更新日期：2001-06-15 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

authors： Dahm PF,Gail MH,Rosenberg PS,Pee D

更新日期：1995-12-15 00:00:00

abstract：:When estimating the average effect of a binary treatment (or exposure) on an outcome, methods that incorporate propensity scores, the G-formula, or targeted maximum likelihood estimation (TMLE) are preferred over naïve regression approaches, which are biased under misspecification of a parametric outcome model. In con...

journal_title：Statistics in medicine

authors： Luque-Fernandez MA,Schomaker M,Rachet B,Schnitzer ME

更新日期：2018-07-20 00:00:00

abstract：:We discuss some of the statistical approaches to the design and analysis of phase I clinical trials in cancer. An attempt is made to identify the issues, particular to this type of trial, that should be addressed by an appropriate methodology. A brief review of schemes currently in use is provided together with our vi...

journal_title：Statistics in medicine

authors： O'Quigley J,Chevret S

更新日期：1991-11-01 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

authors： Bembom O,Petersen ML,Rhee SY,Fessel WJ,Sinisi SE,Shafer RW,van der Laan MJ

更新日期：2009-01-15 00:00:00

abstract：:The Cardiac Arrythmia Suppression Trial was stopped much earlier than planned. Statistical considerations played a very important role in the decision. Flexible group sequential testing was developed for the trial by implementing a Lan and DeMets procedure with use of the permutation test. We compute P-values from the...

journal_title：Statistics in medicine

authors： Pawitan Y,Hallstrom A

更新日期：1990-09-01 00:00:00

abstract：:We describe how trends in the vaccination coverage at 19 months of age vary by race/ethnicity; explore the extent to which data required to evaluate a child's up-to-date vaccination status is missing as a result of the scattering of vaccination records among many vaccination providers; evaluate how the prevalence of t...

journal_title：Statistics in medicine

authors： Smith PJ,Stevenson J

更新日期：2008-09-10 00:00:00

abstract：:The coefficient of individual equivalence is a permutation-based measure of agreement between two observers making replicated readings on each subject. It compares the observed disagreement between the observers to the expected disagreement under individual equivalence. Individual equivalence of observers requires tha...

journal_title：Statistics in medicine

authors： Pan Y,Haber M,Gao J,Barnhart HX

更新日期：2012-09-10 00:00:00

abstract：:We consider counting process methods for analysing time-to-event data with multiple or recurrent outcomes, using the models developed by Anderson and Gill, Wei, Lin and Weissfeld and Prentice, Williams and Peterson. We compare the methods, and show how to implement them using popular statistical software programs. By ...

journal_title：Statistics in medicine

authors： Therneau TM,Hamilton SA

更新日期：1997-09-30 00:00:00

abstract：:The need for resource-intensive laboratory assays to assess exposures in many epidemiologic studies provides ample motivation to consider study designs that incorporate pooled samples. In this paper, we consider the case in which specimens are combined for the purpose of determining the presence or absence of a pool-w...

journal_title：Statistics in medicine

authors： Lyles RH,Tang L,Lin J,Zhang Z,Mukherjee B

更新日期：2012-09-28 00:00:00

abstract：:In recent years, quality control charts have been increasingly applied in the healthcare environment, for example, to monitor surgical performance. Risk-adjusted cumulative (CUSUM) charts that utilize risk scores like the Parsonnet score to estimate the probability of death of a patient from an operation turn out to b...

journal_title：Statistics in medicine

authors： Knoth S,Wittenberg P,Gan FF

更新日期：2019-05-30 00:00:00

abstract：:Service on the Data Monitoring Committee of the CPEP (Calcium for Pre-eclampsia Prevention) has led us to four conclusions about clinical trials which we should like to present to this gathering of biostatisticians for their reactions: (i) meta-analyses of the pertinent published trials of the same therapy should alwa...

journal_title：Statistics in medicine

authors： Chalmers TC,Lau J

更新日期：1996-06-30 00:00:00

abstract：:This paper concerns using modified weighted Schoenfeld residuals to test the proportionality of subdistribution hazards for the Fine-Gray model, similar to the tests proposed by Grambsch and Therneau for independently censored data. We develop a score test for the time-varying coefficients based on the modified Schoen...

journal_title：Statistics in medicine

authors： Zhou B,Fine J,Laird G

更新日期：2013-09-30 00:00:00

abstract：:Non-tumor cell-based model systems have recently gained interest in pharmacogenetic research as a hypothesis generating tool. The hypotheses generated from these model systems can be followed up in functional studies, or tested in individuals taking the same investigational agents. The current cellular phenotypes (e.g...

journal_title：Statistics in medicine

authors： Fridley BL,Jenkins G,Schaid DJ,Wang L

更新日期：2009-09-20 00:00:00

abstract：:We have used Monte Carlo methods to compare the type I error properties of the conditional and unconditional versions of the generalized t and the generalized rank-sum tests to those of the independent samples t and Wilcoxon rank-sum tests. Results showed inflated type I errors for the conditional generalized tests bu...

journal_title：Statistics in medicine

authors： Blair RC,Morel JG

更新日期：1992-02-28 00:00:00

abstract：:The problem of testing symmetry about zero has a long and rich history in the statistical literature. We introduce a new test that sequentially discards observations whose absolute value is below increasing thresholds defined by the data. McNemar's statistic is obtained at each threshold and the largest is used as the...

journal_title：Statistics in medicine

authors： Laska E,Meisner M,Wanderling J

更新日期：2012-11-20 00:00:00

abstract：:Data monitoring committees (DMCs) have become an increasingly common component of randomized clinical trials in recent years. As experience has accumulated, and more individuals and organizations have become involved in such activities, a variety of approaches to the operation of such committees has inevitably arisen....

journal_title：Statistics in medicine

authors： Ellenberg SS

更新日期：2001-09-15 00:00:00

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：:A mixed effect model is proposed to jointly analyze multivariate longitudinal data with continuous, proportion, count, and binary responses. The association of the variables is modeled through the correlation of random effects. We use a quasi-likelihood type approximation for nonlinear variables and transform the prop...

journal_title：Statistics in medicine

authors： Li H,Zhang Y,Carroll RJ,Keadle SK,Sampson JN,Matthews CE

更新日期：2017-11-10 00:00:00

abstract：:The change in c-statistic is frequently used to summarize the change in predictive accuracy when a novel risk factor is added to an existing logistic regression model. We explored the relationship between the absolute change in the c-statistic, Brier score, generalized R(2) , and the discrimination slope when a risk f...

journal_title：Statistics in medicine

authors： Austin PC,Steyerberg EW

更新日期：2013-02-20 00:00:00

abstract：:We obtained maximum likelihood estimates (MLEs) of the proportion cured pi c and mean log survival time mu t for a sample of 4355 patients with intraocular melanoma whose survival times subsequent to treatment were assumed to follow a log-normal distribution. Following stratification by tumour size, MLEs of pi c and m...

journal_title：Statistics in medicine

authors： Gamel JW,McLean IW,Rosenberg SH

更新日期：1990-08-01 00:00:00

abstract：:In the recent years, studies of hepatitis B (HBV) and hepatitis C virus (HCV) dynamics have drawn great attention as they provide insight into the process of virus elimination/production and of infected cells decay during antiviral treatment. Estimates of viral dynamic parameters may be used to determine the lifetime ...

journal_title：Statistics in medicine

authors： Sypsa V,Hatzakis A

更新日期：2008-12-30 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

authors： Espeland MA,Murphy WC,Leverett DH

更新日期：1988-03-01 00:00:00

abstract：:We propose a joint modeling approach to investigating the observed and latent risk factors of mixed types of outcomes. The proposed model comprises three parts. The first part is an exploratory factor analysis model that summarizes latent factors through multiple observed variables. The second part is a proportional h...

journal_title：Statistics in medicine

authors： Pan D,Wei Y,Song X

更新日期：2020-12-09 00:00:00

abstract：:We give up-to-date methods for estimating the age-specific incidence of a disease and for estimating the effect of risk factors. We recommend taking age as the basic time scale of the analysis; then, the hazard function can be interpreted as the age-specific incidence of the disease. This choice raises a delayed entry...

journal_title：Statistics in medicine

authors： Commenges D,Letenneur L,Joly P,Alioum A,Dartigues JF

更新日期：1998-09-15 00:00:00