The Neuro/PsyGRID Calibration Experiment: Identifying Sources of Variance and Bias in Multicenter MRI Studies

John Suckling, Anna Barnes, Dominic Job, David Brennan, Katherine Lymer, Paola Dazzan, Tiago Reis Marques, Clare MacKay, Shane McKie, Steve R. Williams, Steven C. R. Williams, Bill Deakin, Stephen Lawrie

Research output: Contribution to journalArticlepeer-review

Abstract

Calibration experiments precede multicenter trials to identify potential sources of variance and bias. In support of future imaging studies of mental health disorders and their treatment, the Neuro/PsyGRID consortium commissioned a calibration experiment to acquire functional and structural MRI from twelve healthy volunteers attending five centers on two occasions. Measures were derived of task activation from a working memory paradigm, fractal scaling (Hurst exponent) from resting fMRI, and grey matter distributions from T1-weighted sequences. At each intracerebral voxel a fixed-effects analysis of variance estimated components of variance corresponding to factors of center, subject, occasion, and within-occasion order, and interactions of center-by-occasion, subject-by-occasion, and center-by-subject, the latter (since there is no intervention) a surrogate of the expected variance of the treatment effect standard error across centers. A rank order test of between-center differences was indicative of crossover or noncrossover subject-by-center interactions. In general, factors of center, subject and error variance constituted >90% of the total variance, whereas occasion, order, and all interactions were generally

Original languageEnglish
Pages (from-to)373-386
Number of pages14
JournalHuman Brain Mapping
Volume33
Issue number2
DOIs
Publication statusPublished - Feb 2012

Keywords

  • PERMUTATION
  • HUMAN BRAIN
  • magnetic resonance imaging
  • 1.5 T
  • multicentre
  • IMAGES
  • rank test
  • FUNCTIONAL MRI
  • NOISE
  • MAGNETIC-RESONANCE
  • variance components
  • CLINICAL-TRIALS
  • SAMPLE-SIZE
  • FMRI

Fingerprint Dive into the research topics of 'The Neuro/PsyGRID Calibration Experiment: Identifying Sources of Variance and Bias in Multicenter MRI Studies'. Together they form a unique fingerprint.

Cite this