Gabrio, Andrea;
(2019)
Full Bayesian Methods to Handle Missing Data in Health Economic Evaluation.
Doctoral thesis (Ph.D), UCL (University College London).
Preview |
Text
thesis_markup_final.pdf - Accepted Version Download (40MB) | Preview |
Abstract
Trial-based economic evaluations are performed on individual-level data, which almost invariably contain missing values. Missingness represents a threat for the analysis because any statistical method makes assumptions about the unobserved values that cannot be verified from the data at hand; when these assumptions are not realistic, they could lead to biased inferences and mislead the cost-effectiveness assessment. We start by investigating the current missing data handling in economic evaluations and provide recommendations about how information about missingness and related methods should be reported in the analysis. We illustrate the pitfalls and issues that affect the methods used in routine analyses, which typically do not account for the intrinsic complexities of the data and rarely include sensitivity analysis to the missingness assumptions. We propose to overcome these problems using a full Bayesian approach. We use two case studies to demonstrate the benefits of our approach, which allows for a flexible specification of the model to jointly handle the complexities of the data and the uncertainty around the missing values. Finally, we present a longitudinal bivariate model to handle nonignorable missingness. The model extends the standard approach by accounting for all observed data, for which a flexible parametric model is specified. Missing data are handled through a combination of identifying restrictions and sensitivity parameters. First, a benchmark scenario is specified and then plausible nonignorable departures are assessed using alternative prior distributions on the sensitivity parameters. The model is applied to and motivated by one of the two case studies considered.
Type: | Thesis (Doctoral) |
---|---|
Qualification: | Ph.D |
Title: | Full Bayesian Methods to Handle Missing Data in Health Economic Evaluation |
Event: | UCL (University College London) |
Open access status: | An open access version is available from UCL Discovery |
Language: | English |
Additional information: | Copyright © The Author 2019. Original content in this thesis is licensed under the terms of the Creative Commons Attribution 4.0 International (CC BY 4.0) Licence (https://creativecommons.org/licenses/by/4.0/). Any third-party copyright material present remains the property of its respective owner(s) and is licensed under its existing terms. |
UCL classification: | UCL UCL > Provost and Vice Provost Offices > UCL BEAMS UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Maths and Physical Sciences UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Maths and Physical Sciences > Dept of Statistical Science |
URI: | https://discovery.ucl.ac.uk/id/eprint/10072087 |




Archive Staff Only
![]() |
View Item |