title: Reproducibility of fMRI in the clinical setting: implications for trial designs.
abstract: With expanding potential clinical applications of functional magnetic resonance imaging (fMRI) it is important to test how reliable different measures of fMRI activation are between subjects and sessions and between centres. This study compared variability across 17 patients with multiple sclerosis (MS) and 22 age-matched healthy controls (HC) in 5 European centres performing an fMRI block design with hand tapping. We recruited subjects from sites using 1.5 T scanners from different manufacturers. 5 healthy volunteers also were studied at each of 4 of the centres. We found that reproducibility between runs and sessions for single individuals was consistently much greater than between individuals. There was greater run-to-run variability for MS patients than for HC. Measurements of maximum signal change (MSC) appeared to provide higher reproducibility within individuals and greater sensitivity to differences between individuals than region of interest (ROI) suprathreshold voxel counts. The variability in measurements between centres was not as great as that between individuals. Consistent with these observations, we estimated that power should not be reduced substantially with use of multi-, as opposed to single-, centre study designs with similar numbers of subjects. Multi-centre interventional studies in which fMRI is used as an outcome measure thus appear practical even when implemented in conventional clinical environments.
authors.affiliation: Centre for Functional Magnetic Resonance Imaging of the Brain, University of Oxford, UK.
authors.forename: R
authors.initials: R
authors.lastname: Bosnell
authors.forename: C
authors.initials: C
authors.lastname: Wegner
authors.forename: Z T
authors.initials: ZT
authors.lastname: Kincses
authors.forename: T
authors.initials: T
authors.lastname: Korteweg
authors.forename: F
authors.initials: F
authors.lastname: Agosta
authors.forename: O
authors.initials: O
authors.lastname: Ciccarelli
authors.forename: N
authors.initials: N
authors.lastname: De Stefano
authors.forename: A
authors.initials: A
authors.lastname: Gass
authors.forename: J
authors.initials: J
authors.lastname: Hirsch
authors.forename: H
authors.initials: H
authors.lastname: Johansen-Berg
authors.forename: L
authors.initials: L
authors.lastname: Kappos
authors.forename: F
authors.initials: F
authors.lastname: Barkhof
authors.forename: L
authors.initials: L
authors.lastname: Mancini
authors.forename: F
authors.initials: F
authors.lastname: Manfredonia
authors.forename: S
authors.initials: S
authors.lastname: Marino
authors.forename: D H
authors.initials: DH
authors.lastname: Miller
authors.forename: X
authors.initials: X
authors.lastname: Montalban
authors.forename: J
authors.initials: J
authors.lastname: Palace
authors.forename: M
authors.initials: M
authors.lastname: Rocca
authors.forename: C
authors.initials: C
authors.lastname: Enzinger
authors.forename: S
authors.initials: S
authors.lastname: Ropele
authors.forename: A
authors.initials: A
authors.lastname: Rovira
authors.forename: S
authors.initials: S
authors.lastname: Smith
authors.forename: A
authors.initials: A
authors.lastname: Thompson
authors.forename: J
authors.initials: J
authors.lastname: Thornton
authors.forename: T
authors.initials: T
authors.lastname: Yousry
authors.forename: B
authors.initials: B
authors.lastname: Whitcher
authors.forename: M
authors.initials: M
authors.lastname: Filippi
authors.forename: P M
authors.initials: PM
authors.lastname: Matthews
mesh_terms: D000328:Adult; D001931:Brain Mapping / Q000379:methods*; D002986:Clinical Trials as Topic / Q000379:methods*; D005073:Evoked Potentials, Somatosensory; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009103:Multiple Sclerosis / Q000175:diagnosis / Q000503:physiopathology*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013003:Somatosensory Cortex / Q000503:physiopathology*