Inconsistencies with formulas for the standard error of the standardized mean difference of repeated measures experiments.

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：:This paper discusses design considerations and the role of randomization-based inference in randomized community intervention trials. We stress that longitudinal follow-up of cohorts within communities often yields useful information on the effects of intervention on individuals, whereas cross-sectional surveys can us...

journal_title：Statistics in medicine

authors： Gail MH,Mark SD,Carroll RJ,Green SB,Pee D

更新日期：1996-06-15 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：:This article introduces a global hypothesis test intended for studies with multiple endpoints. Our test makes use of a priori predictions about the direction of the result of each endpoint and we weight these predictions using the sample correlation matrix. The global alternative hypothesis concerns a parameter, ...

journal_title：Statistics in medicine

authors： Montgomery RN,Mahnken JD

更新日期：2020-12-10 00:00:00

abstract：:It is unclear to what extent the incremental predictive performance of a novel biomarker is impacted by the method used to control for standard predictors. We investigated whether adding a biomarker to a model with a published risk score overestimates its incremental performance as compared to adding it to a multivari...

journal_title：Statistics in medicine

authors： Xanthakis V,Sullivan LM,Vasan RS,Benjamin EJ,Massaro JM,D'Agostino RB Sr,Pencina MJ

更新日期：2014-07-10 00:00:00

abstract：:In case-control studies, the Cochran-Armitage (CA) trend test is powerful for detection of an association between a risk allele and a marker. To apply this test, a score should be assigned to the genotypes based on the genetic model. When the underlying genetic model is unknown, the trend test statistic is a function ...

journal_title：Statistics in medicine

authors： Zheng G

更新日期：2003-08-30 00:00:00

abstract：:Although the frequentist paradigm has been the predominant approach to clinical trial design since the 1940s, it has several notable limitations. Advancements in computational algorithms and computer hardware have greatly enhanced the alternative Bayesian paradigm. Compared with its frequentist counterpart, the Bayesi...

journal_title：Statistics in medicine

authors： Lee JJ,Chu CT

更新日期：2012-11-10 00:00:00

abstract：:In many studies, interest lies in determining whether members of the study population will undergo a particular event of interest. Such scenarios are often termed 'mover-stayer' scenarios, and interest lies in modelling two sub-populations of 'movers' (those who have a propensity to undergo the event of interest) and ...

journal_title：Statistics in medicine

authors： O'Keeffe AG,Tom BD,Farewell VT

更新日期：2013-02-20 00:00:00

abstract：:Summarizing the information of many studies using a meta-analysis becomes more and more important, also in the field of diagnostic studies. The special challenge in meta-analysis of diagnostic accuracy studies is that in general sensitivity and specificity are co-primary endpoints. Across the studies both endpoints ar...

journal_title：Statistics in medicine

authors： Zapf A,Hoyer A,Kramer K,Kuss O

更新日期：2015-12-20 00:00:00

abstract：:In the recent two decades, data mining methods for signal detection have been developed for drug safety surveillance, using large post-market safety data. Several of these methods assume that the number of reports for each drug-adverse event combination is a Poisson random variable with mean proportional to the unknow...

journal_title：Statistics in medicine

authors： Hu N,Huang L,Tiwari RC

更新日期：2015-08-30 00:00:00

abstract：:A common but not necessarily logical requirement in drug development is that a 'limit of quantitation' be set for chemical assays and that observations that fall below the limit should not be treated as real data but should be labelled as below the limit and set aside for special treatment. We examine five of seven ap...

journal_title：Statistics in medicine

authors： Senn S,Holford N,Hockey H

更新日期：2012-12-30 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

authors： Moyé LA

更新日期：2000-03-30 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

authors： Lin TH,Tsai MH

更新日期：2013-04-30 00:00:00

abstract：:The problem of evaluating an averaged functional magnetic resonance imaging (fMRI) response for repeated block design experiments was considered within a semiparametric regression model with autocorrelated residuals. We applied functional data analysis (FDA) techniques that use a least-squares fitting of B-spline expa...

journal_title：Statistics in medicine

authors： Vakorin VA,Borowsky R,Sarty GE

更新日期：2007-09-20 00:00:00

abstract：:This paper investigates the impact on area life tables of the specification of unobserved frailty. Frailty specification may affect both the regression effects of area and individual level covariates, and lead to changes in the value of summary mortality parameters, such as life expectancy. The paper also investigates...

journal_title：Statistics in medicine

authors： Congdon P

更新日期：1995-09-15 00:00:00

abstract：:For patients who were previously treated for prostate cancer, salvage hormone therapy is frequently given when the longitudinal marker prostate-specific antigen begins to rise during follow-up. Because the treatment is given by indication, estimating the effect of the hormone therapy is challenging. In a previous pape...

journal_title：Statistics in medicine

authors： Taylor JM,Shen J,Kennedy EH,Wang L,Schaubel DE

更新日期：2014-01-30 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：:The analysis of patient-reported outcomes or other psychological traits can be realized using the Rasch measurement model. When the objective of a study is to compare groups of individuals, it is important, before the study, to define a sample size such that the group comparison test will attain a given power. The Ras...

journal_title：Statistics in medicine

authors： Hardouin JB,Blanchin M,Feddag ML,Le Néel T,Perrot B,Sébille V

更新日期：2015-07-20 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：:Analysis of panel data is often challenged by the presence of heterogeneity and state misclassification. In this paper, we propose a hidden mover-stayer model to facilitate heterogeneity for a population that consists of two subpopulations each of movers or of stayers and to simultaneously account for state misclassif...

journal_title：Statistics in medicine

authors： Yi GY,He W,He F

更新日期：2017-09-10 00:00:00

abstract：:Diagnostic problems in medicine are sometimes polytomous, meaning that the outcome has more than two distinct categories. For example, ovarian tumors can be benign, borderline, primary invasive, or metastatic. Extending the main measure of binary discrimination, the c-statistic or area under the ROC curve, to nominal ...

journal_title：Statistics in medicine

authors： Van Calster B,Van Belle V,Vergouwe Y,Timmerman D,Van Huffel S,Steyerberg EW

更新日期：2012-10-15 00:00:00

abstract：:In standard time-to-event or survival analysis, occurrence times of the event of interest are observed exactly or are right-censored, meaning that it is only known that the event occurred after the last observation time. There are numerous methods available for estimating the survival curve and for testing and estimat...

journal_title：Statistics in medicine

authors： Lindsey JC,Ryan LM

更新日期：1998-01-30 00:00:00

abstract：:In drug-drug interaction (DDI) research, a two drug interaction is usually predicted by individual drug pharmacokinetics (PK). Although subject-specific drug concentration data from clinical PK studies on inhibitor/inducer or substrate's PK are not usually published, sample mean plasma drug concentrations and their st...

journal_title：Statistics in medicine

authors： Li L,Yu M,Chin R,Lucksiri A,Flockhart DA,Hall SD

更新日期：2007-09-10 00:00:00

abstract：:In the medical literature, hundreds of prediction models are being developed to predict health outcomes in individuals. For continuous outcomes, typically a linear regression model is developed to predict an individual's outcome value conditional on values of multiple predictors (covariates). To improve model developm...

journal_title：Statistics in medicine

authors： Riley RD,Snell KIE,Ensor J,Burke DL,Harrell FE Jr,Moons KGM,Collins GS

更新日期：2019-03-30 00:00:00

abstract：:This article concerns construction of a confidence surface for tangential slopes of the dose-response surface of a combination therapy to identify where response increases as a function of drug dosage. This approach extends to the assessment of the effectiveness of the combination therapy. ...

journal_title：Statistics in medicine

authors： Hung HM

更新日期：1992-03-01 00:00:00

abstract：:Assay sensitivity has been proposed as a criterion for including psychiatric clinical outcome studies in meta-analyses. The authors assess the performance of assay sensitivity as a method for determining study appropriateness for meta-analysis by calculating expected standard drug vs placebo effect sizes for various c...

journal_title：Statistics in medicine

authors： Gelfand LA,Strunk DR,Tu XM,Noble RE,Derubeis RJ

更新日期：2006-03-30 00:00:00

abstract：:For the analysis of time to event data in contraceptive studies when individuals are subject to competing causes for discontinuation, some authors have recently advocated the use of the cumulative incidence rate as a more appropriate measure to summarize data than the complement of the Kaplan-Meier estimate of discont...

journal_title：Statistics in medicine

authors： Farley TM,Ali MM,Slaymaker E

更新日期：2001-12-15 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

authors： Nagelkerke N,Smits J,le Cessie S,van Houwelingen H

更新日期：2005-01-15 00:00:00

abstract：:The relative importance of prognostic factors in regression can be measured either by standardized regression coefficients or by percentages of explained variation in a dependent variable. One advantage of using explained variation is the direct comparability of qualitative prognostic factors with others, or of groups...

journal_title：Statistics in medicine

authors： Schemper M

更新日期：1993-12-30 00:00:00

abstract：:In the analysis of composite endpoints in a clinical trial, time to first event analysis techniques such as the logrank test and Cox proportional hazard test do not take into account the multiplicity, importance, and the severity of events in the composite endpoint. Several generalized pairwise comparison analysis met...

journal_title：Statistics in medicine

authors： Verbeeck J,Spitzer E,de Vries T,van Es GA,Anderson WN,Van Mieghem NM,Leon MB,Molenberghs G,Tijssen J

更新日期：2019-12-30 00:00:00