A Guide to ComBat Harmonization of Imaging Biomarkers in Multicenter Studies

J Nucl Med. 2022 Feb;63(2):172-179. doi: 10.2967/jnumed.121.262464. Epub 2021 Sep 16.

Abstract

The impact of PET image acquisition and reconstruction parameters on SUV measurements or radiomic feature values is widely documented. This scanner effect is detrimental to the design and validation of predictive or prognostic models and limits the use of large multicenter cohorts. To reduce the impact of this scanner effect, the ComBat method has been proposed and is now used in various contexts. The purpose of this article is to explain and illustrate the use of ComBat based on practical examples. We also give examples in which the ComBat assumptions are not met and, thus, in which ComBat should not be used.

Keywords: harmonization; multicenter studies; radiomics; texture analysis.

Publication types

  • Multicenter Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Biomarkers
  • Image Processing, Computer-Assisted
  • Positron-Emission Tomography* / methods
  • Prognosis
  • Tomography, X-Ray Computed* / methods

Substances

  • Biomarkers