UCL Discovery Stage
UCL home » Library Services » Electronic resources » UCL Discovery Stage

Meta‐analysis of non‐linear exposure‐outcome relationships using individual participant data: A comparison of two methods

White, IR; Kaptoge, S; Royston, P; Sauerbrei, W; (2019) Meta‐analysis of non‐linear exposure‐outcome relationships using individual participant data: A comparison of two methods. Statistics in Medicine , 38 (3) pp. 326-338. 10.1002/sim.7974. Green open access

[thumbnail of Royston VoR White_et_al-2019-Statistics_in_Medicine.pdf]
Preview
Text
Royston VoR White_et_al-2019-Statistics_in_Medicine.pdf - Published Version

Download (1MB) | Preview

Abstract

Non‐linear exposure‐outcome relationships such as between body mass index (BMI) and mortality are common. They are best explored as continuous functions using individual participant data from multiple studies. We explore two two‐stage methods for meta‐analysis of such relationships, where the confounder‐adjusted relationship is first estimated in a non‐linear regression model in each study, then combined across studies. The “metacurve” approach combines the estimated curves using multiple meta‐analyses of the relative effect between a given exposure level and a reference level. The “mvmeta” approach combines the estimated model parameters in a single multivariate meta‐analysis. Both methods allow the exposure‐outcome relationship to differ across studies. Using theoretical arguments, we show that the methods differ most when covariate distributions differ across studies; using simulated data, we show that mvmeta gains precision but metacurve is more robust to model mis‐specification. We then compare the two methods using data from the Emerging Risk Factors Collaboration on BMI, coronary heart disease events, and all‐cause mortality (>80 cohorts, >18 000 events). For each outcome, we model BMI using fractional polynomials of degree 2 in each study, with adjustment for confounders. For metacurve, the powers defining the fractional polynomials may be study‐specific or common across studies. For coronary heart disease, metacurve with common powers and mvmeta correctly identify a small increase in risk in the lowest levels of BMI, but metacurve with study‐specific powers does not. For all‐cause mortality, all methods identify a steep U‐shape. The metacurve and mvmeta methods perform well in combining complex exposure‐disease relationships across studies.

Type: Article
Title: Meta‐analysis of non‐linear exposure‐outcome relationships using individual participant data: A comparison of two methods
Location: England
Open access status: An open access version is available from UCL Discovery
DOI: 10.1002/sim.7974
Publisher version: https://doi.org/10.1002/sim.7974
Language: English
Additional information: © 2018 The Authors. Statistics in Medicine Published by John Wiley & Sons Ltd. This is an open access article under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0/).
Keywords: fractional polynomials, meta-analysis, multivariate meta-analysis, prognostic research, random effects models
UCL classification: UCL
UCL > Provost and Vice Provost Offices > School of Life and Medical Sciences
UCL > Provost and Vice Provost Offices > School of Life and Medical Sciences > Faculty of Population Health Sciences > Inst of Clinical Trials and Methodology
UCL > Provost and Vice Provost Offices > School of Life and Medical Sciences > Faculty of Population Health Sciences > Inst of Clinical Trials and Methodology > MRC Clinical Trials Unit at UCL
URI: https://discovery-pp.ucl.ac.uk/id/eprint/10057888
Downloads since deposit
7,524Downloads
Download activity - last month
Download activity - last 12 months
Downloads by country - last 12 months

Archive Staff Only

View Item View Item