title: Neural network subtyping of depression.
abstract: OBJECTIVE
  To examine the applicability of a neural network classification strategy to examine the independent contribution of psychomotor disturbance (PMD) and endogeneity symptoms to the DSM-III-R definition of melancholia.
  
  
  METHODS
  We studied 407 depressed patients with the clinical dataset comprising 17 endogeneity symptoms and the 18-item CORE measure of behaviourally rated PMD. A multilayer perception neural network was used to fit non-linear models of varying complexity. A linear discriminant function analysis was also used to generate a model for comparison with the non-linear models.
  
  
  RESULTS
  Models (linear and non-linear) using PMD items only and endogeneity symptoms only had similar rates of successful classification, while non-linear models combining both PMD and symptoms scores achieved the best classifications.
  
  
  CONCLUSIONS
  Our current non-linear model was superior to a linear analysis, a finding which may have wider application to psychiatric classification. Our non-linear analysis of depressive subtypes supports the binary view that melancholic and non-melancholic depression are separate clinical disorders rather than different forms of the same entity. This study illustrates how non-linear modelling with neural networks is a potentially fruitful approach to the study of the diagnostic taxonomy of psychiatric disorders and to clinical decision-making.
authors.affiliation: Psychiatry Unit, Prince of Wales Hospital, Randwick, New South Wales, Australia.
authors.forename: T M
authors.initials: TM
authors.lastname: Florio
authors.forename: G
authors.initials: G
authors.lastname: Parker
authors.forename: M P
authors.initials: MP
authors.lastname: Austin
authors.forename: I
authors.initials: I
authors.lastname: Hickie
authors.forename: P
authors.initials: P
authors.lastname: Mitchell
authors.forename: K
authors.initials: K
authors.lastname: Wilhelm
mesh_terms: D001526:Behavioral Symptoms / Q000145:classification; D002493:Central Nervous System Diseases / Q000145:classification; D003866:Depressive Disorder / Q000145:classification*; D016002:Discriminant Analysis; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009069:Movement Disorders / Q000145:classification*; D016571:Neural Networks, Computer; D011569:Psychiatric Status Rating Scales; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index