title: Prediction of illness severity in patients with major depression using structural MR brain scans.
abstract: OBJECTIVE
  To develop a model for the prediction of Major Depressive Disorder (MDD) illness severity ratings from individual structural MRI brain scans.
  
  
  METHODS
  Structural T1-weighted MRI scans were obtained from 30 patients with MDD recruited from two different scanning centers. Self-rated (Beck Depression Inventory; BDI), and clinician-rated (Hamilton Rating Scale for Depression, HRSD), syndrome-specific illness severity ratings were obtained just before scanning. Relevance vector regression (RVR) was used to predict the scores (BDI, HRSD) from T1-weighted MRI scans.
  
  
  RESULTS
  It was possible to predict the BDI score (correlation between actual score and RVR predicted scores r = 0.694; P < 0.0001), but not the HRSD scores (r = 0.34; P = 0.068) from individual subjects. BDI scores from the most ill patients were predicted more accurately than those from patients who were least ill (standard deviation of difference between predicted and actual scores 2.5 versus 7.4, respectively).
  
  
  CONCLUSIONS
  These data suggest that T1-weighted MRI scans contain sufficient information about neurobiological change in patients with MDD to permit accurate predictions about illness severity, on an individual subject basis, particularly for the most ill patients.
authors.affiliation: Centre for Neuroscience, Division of Medical Sciences, Ninewells Hospital and Medical School, University of Dundee, Dundee, United Kingdom. b.m.irungu@dundee.ac.uk
authors.forename: Benson
authors.initials: B
authors.lastname: Mwangi
authors.forename: Keith
authors.initials: K
authors.lastname: Matthews
authors.forename: J Douglas
authors.initials: JD
authors.lastname: Steele
mesh_terms: D000328:Adult; D001499:Bayes Theorem; D001921:Brain / Q000473:pathology*; D001931:Brain Mapping / Q000379:methods; D003865:Major Depressive Disorder / Q000175:diagnosis* / Q000473:pathology; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D015233:Models, Statistical; D012044:Regression Analysis; D015203:Reproducibility of Results; D012720:Severity of Illness Index