A new proposal to adjust Moran's I for population density.

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

authors： Lui KJ

更新日期：1997-08-15 00:00:00

abstract：:A targeted poll was undertaken to compare and contrast models of data monitoring of randomized clinical trials sponsored by the National Institutes of Health. In an attempt to represent the institutes which conduct clinical trials, twelve individuals were selected and asked to respond to a questionnaire specifically p...

journal_title：Statistics in medicine

authors： Geller NL,Stylianou M

更新日期：1993-03-01 00:00:00

abstract：:The development of drugs and biologicals whose mechanisms of action may extend beyond their target indications has led to a need to identify unexpected potential toxicities promptly even while blinded clinical trials are under way. One component of recently issued FDA rules regarding safety reporting requirements rais...

journal_title：Statistics in medicine

authors： Gould AL,Wang WB

更新日期：2017-01-15 00:00:00

abstract：:Writing the variance of the Mantel-Haenszel estimator under the null of homogeneity and inverting the corresponding test, we arrive at an improved confidence interval for the common risk difference in stratified 2 × 2 tables. This interval outperforms a variety of other intervals currently recommended in the literatur...

journal_title：Statistics in medicine

authors： Klingenberg B

更新日期：2014-07-30 00:00:00

abstract：:Novel methodology is implemented to assess the predictive power of covariate information associated with sequential binary events. Logistic models are first fitted on the basis of a subset of the observations and then evaluated sequentially on the rest. The probabilistic forecasts are compared to the outcomes via a sc...

journal_title：Statistics in medicine

authors： Seillier-Moiseiwitsch F

更新日期：1996-10-30 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

authors： Andersen PK,Horowitz MM,Klein JP,Socie G,Stone JV,Zhang MJ

更新日期：1999-06-30 00:00:00

abstract：:This paper is a compendium of exact and asymptotic formulae and tables for estimating the sample size in a clinical trial with two treatment groups and a dichotomous outcome. The paper provides separate formulae for equal and unequal treatment group sizes, formulae for the calculation of power given the sample size, a...

journal_title：Statistics in medicine

authors： Sahai H,Khurshid A

更新日期：1996-01-15 00:00:00

abstract：:Multi-type recurrent event data arise when two or more different kinds of events may occur repeatedly over a period of observation. The scientific objectives in such settings are often to describe features of the marginal processes and to study the association between the different types of events. Interval-censored m...

journal_title：Statistics in medicine

authors： Chen BE,Cook RJ,Lawless JF,Zhan M

更新日期：2005-03-15 00:00:00

abstract：:The proposed guidelines for the assessment of the effect of new pharmaceutical agents on the QT interval (beginning of QRS complex to end of T wave on the electrocardiogram) are based on the maximum of a series over time of simple one-sided 95 per cent upper confidence bounds. This procedure is typically very conserva...

journal_title：Statistics in medicine

authors： Boos DD,Hoffman D,Kringle R,Zhang J

更新日期：2007-09-10 00:00:00

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：:When analyzing time to disease recurrence, we sometimes need to work with data where all the recurrences are recorded, but no information is available on the possible deaths. This may occur when studying diseases of benign nature where patients are only seen at disease recurrences or in poorly-designed registries of b...

journal_title：Statistics in medicine

authors： Štupnik T,Pohar Perme M

更新日期：2016-03-30 00:00:00

abstract：:In many community-based studies on the incidence of dementia, a target population is screened and a subsample is clinically evaluated at baseline and follow-up. Incidence rates are affected by missed cases at both exams and this complicates the estimation of these rates. Recent work proposes a regression-based techniq...

journal_title：Statistics in medicine

authors： Izmirlian G,Brock D,White L

更新日期：2000-06-15 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：:This paper models monthly AIDS diagnosis counts in terms of smooth secular trend, calendar month effects, and the number of workdays per month. A parameterization of month effects allows separation of true seasonal effects from a linear trend over the calendar year and an arbitrary June effect. There is strong evidenc...

journal_title：Statistics in medicine

authors： Bacchetti P

更新日期：1994-10-15 00:00:00

abstract：:Residuals in normal regression are used to assess a model's goodness-of-fit (GOF) and discover directions for improving the model. However, there is a lack of residuals with a characterized reference distribution for censored regression. In this article, we propose to diagnose censored regression with normalized rando...

journal_title：Statistics in medicine

authors： Li L,Wu T,Feng C

更新日期：2020-12-13 00:00:00

abstract：:In this paper, we consider fitting a flexible and interpretable additive regression model in a data-rich setting. We wish to avoid pre-specifying the functional form of the conditional association between each covariate and the response, while still retaining interpretability of the fitted functions. A number of recen...

journal_title：Statistics in medicine

authors： Petersen A,Witten D

更新日期：2019-02-20 00:00:00

abstract：:In medical research, risk difference (RD) and number needed to treat (NNT) measures for survival times have been mainly proposed without consideration of covariates. In this paper, we develop adjusted RD and NNT measures for use in observational studies with survival time outcomes within the framework of the Cox propo...

journal_title：Statistics in medicine

authors： Laubender RP,Bender R

更新日期：2010-03-30 00:00:00

abstract：:Generalized linear models are often assumed to fit propensity scores, which are used to compute inverse probability weighted (IPW) estimators. To derive the asymptotic properties of IPW estimators, the propensity score is supposed to be bounded away from zero. This condition is known in the literature as strict positi...

journal_title：Statistics in medicine

authors： Molina J,Sued M,Valdora M

更新日期：2018-10-30 00:00:00

abstract：:We consider bivariate survival times for heterogeneous populations, where heterogeneity induces deviations in an individual's risk of an event as well as associations between survival times. The heterogeneity is characterized by a bivariate frailty model. We measure the heterogeneity effects through deviations associa...

journal_title：Statistics in medicine

authors： Xue X,Ding Y

更新日期：1999-04-30 00:00:00

abstract：:We examine the use of randomization-based inference for analyzing multiarmed randomized clinical trials, including the application of conditional randomization tests to multiple comparisons. The view is taken that the linkage of the statistical test to the experimental design (randomization procedure) should be recogn...

journal_title：Statistics in medicine

authors： Wang Y,Rosenberger WF,Uschner D

更新日期：2020-02-20 00:00:00

abstract：:This paper develops methods of analysis for active extension clinical trials. Under this design, patients are randomized to treatment or placebo for a period of time (period 1), and then all patients receive treatment for an additional period of time (period 2). We assume a continuous outcome is measured at baseline a...

journal_title：Statistics in medicine

authors： Hu Z,Follmann D

更新日期：2007-05-30 00:00:00

abstract：:Many different methods have been proposed for the analysis of cluster randomized trials (CRTs) over the last 30 years. However, the evaluation of methods on overdispersed count data has been based mostly on the comparison of results using empiric data; i.e. when the true model parameters are not known. In this study, ...

journal_title：Statistics in medicine

authors： Durán Pacheco G,Hattendorf J,Colford JM Jr,Mäusezahl D,Smith T

更新日期：2009-10-30 00:00:00

abstract：:Instrumental variable estimates of causal effects can be biased when using many instruments that are only weakly associated with the exposure. We describe several techniques to reduce this bias and estimate corrected standard errors. We present our findings using a simulation study and an empirical application. For th...

journal_title：Statistics in medicine

authors： Davies NM,von Hinke Kessler Scholder S,Farbmacher H,Burgess S,Windmeijer F,Smith GD

更新日期：2015-02-10 00:00:00

abstract：:Meta analysis is a collection of quantitative methods devoted to combine summary information from related but independent studies. Because research reports usually present only data reductions and summary statistics rather than detailed data, the reviewer must often resort to rather crude methods for constructing summ...

journal_title：Statistics in medicine

authors： Di Pietrantonj C

更新日期：2006-07-15 00:00:00

abstract：:In longitudinal studies with incomplete data, where the number of time points can become numerous, it is often advantageous to model the covariance matrix. We describe several covariance models (for example, mixed models, compound symmetry, AR(1)-type models, and combination models) that offer parsimonious alternative...

journal_title：Statistics in medicine

authors： Grady JJ,Helms RW

更新日期：1995-07-15 00:00:00

abstract：:Propensity score analysis is widely used in observational studies to adjust for confounding and estimate the causal effect of a treatment on the outcome. When the outcome is survival time, there are special considerations on the definition of the causal estimand, point, and variance estimation that have not been thoro...

journal_title：Statistics in medicine

authors： Mao H,Li L,Yang W,Shen Y

更新日期：2018-11-20 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：: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：:Age-period-cohort (APC) analysis is widely used in cancer epidemiology to model trends in cancer rates. We develop methods for comparative APC analysis of two independent cause-specific hazard rates assuming that an APC model holds for each one. We construct linear hypothesis tests to determine whether the two hazards...

journal_title：Statistics in medicine

authors： Rosenberg PS,Anderson WF

更新日期：2010-05-20 00:00:00

abstract：:Before introducing a new measurement tool it is necessary to evaluate its performance. Several statistical methods have been developed, or used, to evaluate the reliability and validity of a new assessment method in such circumstances. In this paper we review some commonly used methods. Data from a study that was cond...

journal_title：Statistics in medicine

authors： White SA,van den Broek NR

更新日期：2004-05-30 00:00:00