title: Disorders without borders: current and future directions in the meta-structure of mental disorders.
abstract: OBJECTIVE
  Classification is the cornerstone of clinical diagnostic practice and research. However, the extant psychiatric classification systems are not well supported by research evidence. In particular, extensive comorbidity among putatively distinct disorders flags an urgent need for fundamental changes in how we conceptualize psychopathology. Over the past decade, research has coalesced on an empirically based model that suggests many common mental disorders are structured according to two correlated latent dimensions: internalizing and externalizing.
  
  
  METHODS
  We review and discuss the development of a dimensional-spectrum model which organizes mental disorders in an empirically based manner. We also touch upon changes in the DSM-5 and put forward recommendations for future research endeavors.
  
  
  RESULTS
  Our review highlights substantial empirical support for the empirically based internalizing-externalizing model of psychopathology, which provides a parsimonious means of addressing comorbidity.
  
  
  CONCLUSIONS
  As future research goals, we suggest that the field would benefit from: expanding the meta-structure of psychopathology to include additional disorders, development of empirically based thresholds, inclusion of a developmental perspective, and intertwining genomic and neuroscience dimensions with the empirical structure of psychopathology.
authors.affiliation: National Drug and Alcohol Research Centre, University of New South Wales, Sydney, NSW, 2052, Australia, n.carragher@unsw.edu.au.
authors.forename: Natacha
authors.initials: N
authors.lastname: Carragher
authors.forename: Robert F
authors.initials: RF
authors.lastname: Krueger
authors.forename: Nicholas R
authors.initials: NR
authors.lastname: Eaton
authors.forename: Tim
authors.initials: T
authors.lastname: Slade
mesh_terms: D006801:Humans; D001523:Mental Disorders / Q000145:classification* / Q000150:complications / Q000175:diagnosis*; D008960:Models, Psychological; D011569:Psychiatric Status Rating Scales