A multiphase non-linear mixed effects model: An application to spirometry after lung transplantation.

abstract：:Pediatric cardiac surgery may lead to poor outcomes such as acute kidney injury (AKI) and prolonged hospital length of stay (LOS). Plasma and urine biomarkers may help with early identification and prediction of these adverse clinical outcomes. In a recent multi-center study, 311 children undergoing cardiac surgery we...

journal_title：Statistical methods in medical research

authors： Wang Z,Ma S,Zappitelli M,Parikh C,Wang CY,Devarajan P

更新日期：2016-12-01 00:00:00

abstract：:The positivity assumption, or the experimental treatment assignment (ETA) assumption, is important for identifiability in causal inference. Even if the positivity assumption holds, practical violations of this assumption may jeopardize the finite sample performance of the causal estimator. One of the consequences of p...

journal_title：Statistical methods in medical research

authors： Ju C,Schwab J,van der Laan MJ

更新日期：2019-06-01 00:00:00

abstract：:In genomic analysis, it is significant though challenging to identify markers associated with cancer outcomes or phenotypes. Based on the biological mechanisms of cancers and the characteristics of datasets, we propose a novel integrative interaction approach under a semiparametric model, in which genetic and environm...

journal_title：Statistical methods in medical research

authors： Li Y,Wang F,Li R,Sun Y

更新日期：2020-10-01 00:00:00

abstract：:Censored data make survival analysis more complicated because exact event times are not observed. Statistical methodology developed to account for censored observations assumes that patients' withdrawal from a study is independent of the event of interest. However, in practice, some covariates might be associated to b...

journal_title：Statistical methods in medical research

authors： Willems S,Schat A,van Noorden MS,Fiocco M

更新日期：2018-02-01 00:00:00

abstract：:Within paediatric populations, there may be distinct age groups characterised by different exposure-response relationships. Several regulatory guidance documents have suggested general age groupings. However, it is not clear whether these categorisations will be suitable for all new medicines and in all disease areas....

journal_title：Statistical methods in medical research

authors： Wadsworth I,Hampson LV,Bornkamp B,Jaki T

更新日期：2020-09-01 00:00:00

abstract：:Clinical trials investigating the efficacy of two or more doses of an experimental treatment compared to a single reference arm are not uncommon. In such situations, if each dose is compared to the reference arm using an un-adjusted significance level, consideration of the Type I familywise error is likely to be requi...

journal_title：Statistical methods in medical research

authors： Fernandes N,Stone A

更新日期：2011-12-01 00:00:00

abstract：:Publication bias frequently appears in meta-analyses when the included studies' results (e.g., p-values) influence the studies' publication processes. Some unfavorable studies may be suppressed from publication, so the meta-analytic results may be biased toward an artificially favorable direction. Many statistical tes...

journal_title：Statistical methods in medical research

authors： Lin L

更新日期：2020-10-01 00:00:00

abstract：:Measurement error is a serious problem in the analysis of epidemiological data. In the past 20 years, a large number of methods for the correction of measurement error have been developed. While at the beginning mostly methods for cohort studies were considered, recently more attention has been paid to case-control st...

journal_title：Statistical methods in medical research

authors： Thürigen D,Spiegelman D,Blettner M,Heuer C,Brenner H

更新日期：2000-10-01 00:00:00

abstract：:Health data may be collected across one spatial framework (e.g. health provider agencies), but contrasts in health over another spatial framework (neighbourhoods) may be of policy interest. In the UK, population prevalence totals for chronic diseases are provided for populations served by general practitioner practice...

journal_title：Statistical methods in medical research

authors： Congdon P

更新日期：2014-04-01 00:00:00

abstract：:For semi-continuous data which are a mixture of true zeros and continuously distributed positive values, the use of two-part mixed models provides a convenient modelling framework. However, deriving population-averaged (marginal) effects from such models is not always straightforward. Su et al. presented a model that ...

journal_title：Statistical methods in medical research

authors： Tom BD,Su L,Farewell VT

更新日期：2016-10-01 00:00:00

abstract：:The analysis of walking behavior in a physical activity intervention is considered. A Bayesian latent structure modeling approach is proposed whereby the ability and willingness of participants is modeled via latent effects. The dropout process is jointly modeled via a linked survival model. Computational issues are a...

journal_title：Statistical methods in medical research

authors： Lawson AB,Ellerbe C,Carroll R,Alia K,Coulon S,Wilson DK,VanHorn ML,George SM

更新日期：2016-12-01 00:00:00

abstract：:The simple yet subtle concept of regression towards the mean is reviewed historically. Verbal, geometric, and mathematical expressions of the concept date to the discoverer of the concept, Francis Galton. That discovery and subsequent understanding (and misunderstanding) of the concept are surveyed. ...

journal_title：Statistical methods in medical research

authors： Stigler SM

更新日期：1997-06-01 00:00:00

abstract：:Statistical methods for spatial health data to identify the significant covariates associated with the health outcomes are of critical importance. Most studies have developed variable selection approaches in which the covariates included appear within the spatial domain and their effects are fixed across space. Howeve...

journal_title：Statistical methods in medical research

authors： Choi J,Lawson AB

更新日期：2018-01-01 00:00:00

abstract：:To evaluate the antiretroviral activity of antiretroviral agents and to compare the effects of two different antiretroviral agents, we propose a non-parametric mixed-effects model to investigate change of CD4+ counts. The proposed model and methods are applied to analyse the data from PACTG345 study. Population and in...

journal_title：Statistical methods in medical research

authors： Liang H

更新日期：2008-04-01 00:00:00

abstract：:One of the main advantages of Bayesian analyses of clinical trials is their ability to formally incorporate skepticism about large treatment effects through the use of informative priors. We conducted a simulation study to assess the performance of informative normal, Student- t, and beta distributions in estimating r...

journal_title：Statistical methods in medical research

authors： Pedroza C,Han W,Truong VTT,Green C,Tyson JE

更新日期：2018-01-01 00:00:00

abstract：:One purpose of a longitudinal study is to gain a better understanding of how an outcome of interest changes among a given population over time. In what follows, a trajectory will be taken to mean the series of measurements of the outcome variable for an individual. Group-based trajectory modelling methods seek to iden...

journal_title：Statistical methods in medical research

authors： Davies CE,Glonek GF,Giles LC

更新日期：2017-08-01 00:00:00

abstract：:The accuracy of a diagnostic test, which is often quantified by a pair of measures such as sensitivity and specificity, is critical for medical decision making. Separate studies of an investigational diagnostic test can be combined through meta-analysis; however, such an analysis can be threatened by publication bias....

journal_title：Statistical methods in medical research

authors： Piao J,Liu Y,Chen Y,Ning J

更新日期：2019-10-01 00:00:00

abstract：:Variable selection in semiparametric mixed models for longitudinal data remains a challenge, especially in the presence of multiple correlated outcomes. In this paper, we propose a model selection procedure that simultaneously selects fixed and random effects using a maximum penalized likelihood method with the adapti...

journal_title：Statistical methods in medical research

authors： Li Z,Liu H,Tu W

更新日期：2018-10-01 00:00:00

abstract：:Many statistical studies report p-values for inferential purposes. In several scenarios, the stochastic aspect of p-values is neglected, which may contribute to drawing wrong conclusions in real data experiments. The stochastic nature of p-values makes their use to examine the performance of given testing procedures o...

journal_title：Statistical methods in medical research

authors： Vexler A,Yu J,Zhao Y,Hutson AD,Gurevich G

更新日期：2018-12-01 00:00:00

abstract：:Sample selection arises when the outcome of interest is partially observed in a study. Although sophisticated statistical methods in the parametric and non-parametric framework have been proposed to solve this problem, it is yet unclear how to deal with selectively missing covariate data using simple multiple imputati...

journal_title：Statistical methods in medical research

authors： Ogundimu EO,Collins GS

更新日期：2019-01-01 00:00:00

abstract：:In multi-regional trials, the underlying overall and region-specific accrual rates often do not hold constant over time and different regions could have different start-up times, which combined with initial jump in accrual within each region often leads to a discontinuous overall accrual rate, and these issues associa...

journal_title：Statistical methods in medical research

authors： Deng Y,Zhang X,Long Q

更新日期：2017-04-01 00:00:00

abstract：:Sensitive questions are often involved in healthcare or medical survey research. Much empirical evidence has shown that the randomized response technique is useful for the collection of truthful responses. However, few studies have discussed methods to estimate the dependence of sensitive responses of multiple types. ...

journal_title：Statistical methods in medical research

authors： Chu AM,So MK,Chan TW,Tiwari A

更新日期：2020-03-01 00:00:00

abstract：:This paper presents a new model-based generalized functional clustering method for discrete longitudinal data, such as multivariate binomial and Poisson distributed data. For this purpose, we propose a multivariate functional principal component analysis (MFPCA)-based clustering procedure for a latent multivariate Gau...

journal_title：Statistical methods in medical research

authors： Lim Y,Cheung YK,Oh HS

更新日期：2020-11-01 00:00:00

abstract：:This article discusses and extends statistical models to jointly analyse the spatial variation of rates of several diseases with common risk factors. We start with a review of methods for separate analyses of diseases, then move to ecological regression approaches, where the rates from one of the diseases enter as sur...

journal_title：Statistical methods in medical research

authors： Held L,Natário I,Fenton SE,Rue H,Becker N

更新日期：2005-02-01 00:00:00

abstract：:Previous work has shown that individual randomized "proof-of-concept" (PoC) studies may be designed to maximize cost-effectiveness, subject to an overall PoC budget constraint. Maximizing cost-effectiveness has also been considered for arrays of simultaneously executed PoC studies. Defining Type III error as the oppor...

journal_title：Statistical methods in medical research

authors： He L,Du L,Antonijevic Z,Posch M,Korostyshevskiy VR,Beckman RA

更新日期：2020-09-21 00:00:00

abstract：:In the past two decades, it has become increasingly clear that genetic factors contribute to the aetiology of many common diseases including cancers, coronary disease, allergy and psychiatric disorders. While one goal of genetic epidemiological studies is to locate susceptibility genes for these complex diseases, it i...

journal_title：Statistical methods in medical research

authors： Liang KY,Beaty TH

更新日期：2000-12-01 00:00:00

abstract：:Appropriate handling of aggregate missing outcome data is necessary to minimise bias in the conclusions of systematic reviews. The two-stage pattern-mixture model has been already proposed to address aggregate missing continuous outcome data. While this approach is more proper compared with the exclusion of missing co...

journal_title：Statistical methods in medical research

authors： Spineli LM,Kalyvas C,Papadimitropoulou K

更新日期：2021-01-06 00:00:00

abstract：:Cancer mortality risk estimates are essential for planning resource allocation and designing and evaluating cancer prevention and management strategies. However, mortality figures generally become available after a few years, making necessary to develop reliable procedures to provide current and near future mortality ...

journal_title：Statistical methods in medical research

authors： Ugarte MD,Goicoa T,Etxeberria J,Militino AF

更新日期：2012-10-01 00:00:00

abstract：:This review provides an overview of forensic inference from genetic markers. Because the judge and jurors are charged with decision-making, the forensic expert's job is to provide a useful summary of the evidence to the court. Hence, this review focuses on the likelihood ratio as a means of summarizing the genetic dat...

journal_title：Statistical methods in medical research

authors： Devlin B

更新日期：1993-01-01 00:00:00

abstract：:Common limitations of clustering methods include the slow algorithm convergence, the instability of the pre-specification on a number of intrinsic parameters, and the lack of robustness to outliers. A recent clustering approach proposed a fast search algorithm of cluster centers based on their local densities. However...

journal_title：Statistical methods in medical research

authors： Wang XF,Xu Y

更新日期：2017-12-01 00:00:00