title: Meta-regression with partial information on summary trial or patient characteristics.
abstract: We present a model for meta-regression in the presence of missing information on some of the study level covariates, obtaining inferences using Bayesian methods. In practice, when confronted with missing covariate data in a meta-regression, it is common to carry out a complete case or available case analysis. We propose to use the full observed data, modelling the joint density as a factorization of a meta-regression model and a conditional factorization of the density for the covariates. With the inclusion of several covariates, inter-relations between these covariates are modelled. Under this joint likelihood-based approach, it is shown that the lesser assumption of the covariates being Missing At Random is imposed, instead of the more usual Missing Completely At Random (MCAR) assumption. The model is easily programmable in WinBUGS, and we examine, through the analysis of two real data sets, sensitivity and robustness of results to the MCAR assumption.
authors.affiliation: Department of Public Health, Epidemiology and Biostatistics, University of Birmingham, UK. k.hemming@bham.ac.uk
authors.forename: K
authors.initials: K
authors.lastname: Hemming
authors.forename: J L
authors.initials: JL
authors.lastname: Hutton
authors.forename: M G
authors.initials: MG
authors.lastname: Maguire
authors.forename: A G
authors.initials: AG
authors.lastname: Marson
mesh_terms: D000927:Anticonvulsants / Q000494:pharmacology; D001499:Bayes Theorem; D056808:Biostatistics; D002986:Clinical Trials as Topic / Q000706:statistics & numerical data; D006801:Humans; D016013:Likelihood Functions; D015201:Meta-Analysis as Topic; D015233:Models, Statistical; D015999:Multivariate Analysis; D012044:Regression Analysis; D020888:Vigabatrin / Q000494:pharmacology
chemical_list: D000927:Anticonvulsants; D020888:Vigabatrin