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Parameter estimation of complex mixed models based on meta-model approach

Pierre Barbillon, Célia Barthélémy, Adeline Samson
2016 Statistics and computing  
A control on the distance between the maximum likelihood estimates in this mixed meta-model and the maximum likelihood estimates obtained with the exact mixed model is guaranteed.  ...  When there is no analytical solution, a classical estimation approach relies on the coupling of a stochastic version of the EM algorithm (SAEM) with a MCMC algorithm.  ...  Three mixed meta-models The estimation of the population parameter θ is performed on the meta-model approximation of the mixed model (1).  ... 
doi:10.1007/s11222-016-9674-x fatcat:ysfkwlk7indvpd27stvfpjgfsm

Using Generalized Linear Mixed Models to Evaluate Inconsistency within a Network Meta-Analysis

Yu-Kang Tu
2015 Value in Health  
We also compared contrast-based and arm-based models in the evaluation of design inconsistency when different heterogeneity variances were estimated, and the arm-based model yielded more accurate results  ...  Objective: The aim of this article was to show how to evaluate the design-by-treatment interaction model using the generalized linear mixed model.  ...  linear mixed model by Higgins et al. and from the proposed arm-based generalized linear mixed model.Contrast-based linear mixed modelArm-based generalized linear mixed model Model parameters Consistency  ... 
doi:10.1016/j.jval.2015.10.002 pmid:26686799 fatcat:aze3c4jx3bfehcna3t4cjsxnhe

Deriving percentage study weights in multi-parameter meta-analysis models: with application to meta-regression, network meta-analysis and one-stage individual participant data models

Richard D Riley, Joie Ensor, Dan Jackson, Danielle L Burke
2017 Statistical Methods in Medical Research  
This approach generalises how percentage weights are calculated in a traditional, single parameter meta-analysis model.  ...  In particular, meta-regression models may contain multiple study-level covariates, and one-stage individual participant data meta-analysis models may contain multiple patient-level covariates and interactions  ...  Acknowledgements We thank Ian White for helpful comments on an early draft of this work, and a reviewer for helpful feedback that helped us to improve the article upon revision.  ... 
doi:10.1177/0962280216688033 pmid:28162044 pmcid:PMC6146321 fatcat:3fbxhfioprbplaxakbpjhv7etm

Using structural equation modeling for network meta-analysis

Yu-Kang Tu, Yun-Chun Wu
2017 BMC Medical Research Methodology  
We also showed that a new approach to network meta-analysis based on the technique of unrestricted weighted least squares (UWLS) method can also be undertaken using SEM.  ...  As random effect is explicitly modeled as a latent variable in SEM, it is very flexible for analysts to specify complex random effect structure and to make linear and nonlinear constraints on parameters  ...  Availability of data and materials All data generated or analysed during this study are included in the Additional file 1.  ... 
doi:10.1186/s12874-017-0390-9 pmid:28709406 pmcid:PMC5512972 fatcat:3iwymqdkvzh4tl6pt7tzbgcdva

One-stage random effects meta-analysis using linear mixed models for aggregate continuous outcome data

Katerina Papadimitropoulou, Theo Stijnen, Olaf M Dekkers, Saskia le Cessie
2018 Research Synthesis Methods  
When the outcome is continuous and IPD are available, linear mixed modelling methods canbe employed in a one-stage approach.  ...  The vast majority of meta-analyses uses summary/aggregate data retrieved from published studies in contrast to meta-analysis of individual participant data (IPD).  ...  Results on iron blood levels We compare the results of the 12 models fitted with the pseudo IPD data to the three commonly used two-stage meta analysis approaches based on aggregate mean differences and  ... 
doi:10.1002/jrsm.1331 pmid:30523676 pmcid:PMC6767371 fatcat:gmigukyskjb27peizisbnfu3e4

Fitting parametric random effects models in very large data sets with application to VHA national data

Mulugeta Gebregziabher, Leonard Egede, Gregory E Gilbert, Kelly Hunt, Paul J Nietert, Patrick Mauldin
2012 BMC Medical Research Methodology  
Thus, this study proposes and assesses the performance of a meta regression approach and makes comparison with methods based on sampling of the full data.  ...  Using this outcome, we compared parameter estimates from the proposed random effects meta regression (REMR) with estimates based on simple random sampling and VISN (Veterans Integrated Service Networks  ...  The manuscript represents the views of the authors and not those of the Department of Veterans Affairs, the United States Government 2.  ... 
doi:10.1186/1471-2288-12-163 pmid:23095325 pmcid:PMC3542162 fatcat:puefvmcsanbkhjimq2ljhb23ty

A frequentist one-step model for a simple network meta-analysis of time-to-event data in presence of an effect modifier

Matthieu Faron, Pierre Blanchard, Laureen Ribassin-Majed, Jean-Pierre Pignon, Stefan Michiels, Gwénaël Le Teuff, Mona Pathak
2021 PLoS ONE  
In the real data example, Cox and Poisson IPD-based models gave similar estimations of the model parameters.  ...  Methods One-step, frequentist, IPD-based Cox and Poisson generalized linear mixed models were proposed.  ...  Acknowledgments We thank the investigators and associated research groups of the Meta-Analysis of Chemotherapy in Head and Neck Cancer/Meta-Analysis of Radiotherapy in Squamous Cell Carcinomas of Head  ... 
doi:10.1371/journal.pone.0259121 pmid:34723994 pmcid:PMC8559936 fatcat:i3jvb4xtfzc2xoc3qsxfterpbi

PRM69 Network Meta-Analysis of Interventions for Overactive Bladder and Detrusor Instability – a Hierarchical Modelling Approach

R.K. Owen, K. Abrams, D.G. Tincello
2012 Value in Health  
OBJECTIVES: To demonstrate a simplified approach to cost-effectiveness analysis of new diagnostic tests based on minimal information and without developing a full decision-analytic modeling framework,  ...  which is often complex, time consuming and potentially inefficient.  ...  In this DES model parameters, attributes and distributions were estimated based on patient population (patient-level DES model).  ... 
doi:10.1016/j.jval.2012.08.1532 fatcat:c7naf2heyvb33jnq6k2tuu6zjq

PRM66 Discrete Event Simulation: Modeling Simultaneous Complications and Outcomes

E.H. Quik, T.L. Feenstra, P.F.M. Krabbe
2012 Value in Health  
OBJECTIVES: To demonstrate a simplified approach to cost-effectiveness analysis of new diagnostic tests based on minimal information and without developing a full decision-analytic modeling framework,  ...  which is often complex, time consuming and potentially inefficient.  ...  In this DES model parameters, attributes and distributions were estimated based on patient population (patient-level DES model).  ... 
doi:10.1016/j.jval.2012.08.1529 fatcat:mh6k4ufy7rfudbbdl4kkhz3pem

Parametric estimation of complex mixed models based on meta-model approach [article]

Pierre Barbillon, Célia Barthélémy
2015 arXiv   pre-print
A control on the distance between the maximum likelihood estimates in this mixed meta-model and the maximum likelihood estimates obtained with the exact mixed model is guaranteed.  ...  When there is no analytical solution, a classical estimation approach relies on the coupling of a stochastic version of the EM algorithm (SAEM) with a MCMC algorithm.  ...  Three mixed meta-models The estimation of the population parameter θ is performed on the meta-model approximation of the mixed model (1).  ... 
arXiv:1506.03313v1 fatcat:afpbb2chqfbg5obayczkpgmhcq

Efficient two-step multivariate random effects meta-analysis of individual participant data for longitudinal clinical trials using mixed effects models

Hisashi Noma, Kazushi Maruo, Masahiko Gosho, Stephen Z. Levine, Yair Goldberg, Stefan Leucht, Toshi A. Furukawa
2019 BMC Medical Research Methodology  
In meta-analysis of individual participant data (IPD) based on these longitudinal studies, joint synthesis of the regression coefficient parameters can improve efficiency, especially for explorations of  ...  Mixed effects models have been widely applied in clinical trials that involve longitudinal repeated measurements, which possibly contain missing outcome data.  ...  Science (Grant numbers: JP15K15954, JP17K19808) in the design of the study and collection, analysis, and interpretation of data and in writing the manuscript.  ... 
doi:10.1186/s12874-019-0676-1 pmid:30764757 pmcid:PMC6376708 fatcat:j4ir74n43zd33okkgkb43yv4yy

Evidence Synthesis for Decision Making 6

Sofia Dias, Alex J. Sutton, Nicky J. Welton, A. E. Ades
2013 Medical decision making  
Network meta-analysis (mixed treatment comparisons) is one example where such correlations occur, along with meta-regression and syntheses involving multiple related outcomes.  ...  Frequentist methods of parameter estimation followed by forward Monte Carlo simulation from the maximum likelihood estimates and their variance-covariance matrix represent a third approach.  ...  ACKNOWLEDGMENTS The authors thank Jenny Dunn at NICE DSU and Rachael Fleurence, Jeroen Jansen, Alec Miners, Jaime Peters, Mike Spencer, and the team at NICE, led by Gabriel Rogers, for reviewing earlier versions of  ... 
doi:10.1177/0272989x13487257 pmid:23804510 pmcid:PMC3704202 fatcat:ltgu32bpjbau7au6k2azjilk4e

Multivariate meta-analysis for non-linear and other multi-parameter associations

A. Gasparrini, B. Armstrong, M. G. Kenward
2012 Statistics in Medicine  
In this paper, we formalize the application of multivariate meta-analysis and meta-regression to synthesize estimates of multi-parameter associations obtained from different studies.  ...  The model The framework we use is nested within that of the multivariate normal linear mixed model and so follows well-developed lines [27] .  ...  , on 26 January 2010.  ... 
doi:10.1002/sim.5471 pmid:22807043 pmcid:PMC3546395 fatcat:rbdujaxh4rf3hkv34miyvx4kpa

PRM68 Comparative Computation Speed of Excel, Visual Basic for Applications, R, and Java in Execution of a Microsimulation Model With Probabilistic Sensitivity Analysis

S.J. Snedecor, X. Ji, V. Ektare, M. Treur
2012 Value in Health  
OBJECTIVES: To demonstrate a simplified approach to cost-effectiveness analysis of new diagnostic tests based on minimal information and without developing a full decision-analytic modeling framework,  ...  which is often complex, time consuming and potentially inefficient.  ...  In this DES model parameters, attributes and distributions were estimated based on patient population (patient-level DES model).  ... 
doi:10.1016/j.jval.2012.08.1531 fatcat:kgrfygpnhzfwzi7fxesw7apd5q

Individual participant data meta-analysis of continuous outcomes: A comparison of approaches for specifying and estimating one-stage models

Amardeep Legha, Richard D. Riley, Joie Ensor, Kym I.E. Snell, Tim P. Morris, Danielle L. Burke
2018 Statistics in Medicine  
One-stage individual participant data meta-analysis models should account for within-trial clustering, but it is currently debated how to do this.  ...  of the summary treatment effect estimate are very similar when using stratified or random intercept models with restricted maximum likelihood, and thus either approach could be taken in practice, (ii)  ...  It also allows greater flexibility of parameter specification over the two-stage approach. 6 When conducting a one-stage IPD meta-analysis, it is important to account for clustering of participants within  ... 
doi:10.1002/sim.7930 pmid:30101507 fatcat:dedcwwmgdbgevouz6vny6n6xju
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