The psychosis continuum and categorical versus dimensional diagnostic approaches

Article

Abstract

This overview briefly presents recent thinking on the dimensional approach to understanding psychotic experiences. First, evidence is provided for a continuum of psychosis ranging from self-reported infrequent psychotic symptoms in the general population, to schizotypal traits, to schizotypal personality disorder, and finally to full-blown psychosis resulting in a diagnosable primary psychotic disorder. Variation within each of these types of psychotic experience is discussed. Then, a comparison is presented between categorical and dimensional approaches to the diagnosis of psychosis by highlighting four advantages of each approach. In doing so, it is emphasized that the categorical approach is beneficial primarily in terms of reliability, whereas the dimensional approach would enhance validity.

References and Recommended Reading

  1. 1.
    American Psychiatric Association: Diagnostic and Statistical Manual of Mental Disorders, edn 4 (text revision). Washington, DC: American Psychiatric Association; 2000.Google Scholar
  2. 2.
    Krabbendam L, Myin-Germeys I, Bak M, van Os J: Explaining transitions over the hypothesized psychosis continuum. Aust N Z J Psychiatry 2005, 39:180–186.PubMedCrossRefGoogle Scholar
  3. 3.
    Livingston G, Kitchen G, Manela M, et al.: Persecutory symptoms and perceptual disturbance in a community sample of older people: the Islington study. Int J Geriatr Psychiatry 2001, 16:462–468.PubMedCrossRefGoogle Scholar
  4. 4.
    Lundberg P, Cantor-Graae E, Kabakyenga J, et al.: Prevalence of delusional ideation in a district in southwestern Uganda. Schizophr Res 2004, 71:27–34.PubMedCrossRefGoogle Scholar
  5. 5.
    Wiles NJ, Zammit S, Bebbington P, et al.: Self-reported psychotic symptoms in the general population: results from the longitudinal study of the British National Psychiatric Morbidity Survey. Br J Psychiatry 2006, 188:519–526.PubMedCrossRefGoogle Scholar
  6. 6.
    Verdoux H, van Os J: Psychotic symptoms in non-clinical populations and the continuum of psychosis. Schizophr Res 2002, 54:59–65.PubMedCrossRefGoogle Scholar
  7. 7.
    Freeman D, Garety PA, Bebbington PE, et al.: Psychological investigation of the structure of paranoia in a non-clinical population. Br J Psychiatry 2005, 186:427–435.PubMedCrossRefGoogle Scholar
  8. 8.
    Johns LC, Cannon M, Singleton N, et al.: Prevalence and correlates of self-reported psychotic symptoms in the British population. Br J Psychiatry 2004, 185:298–305.PubMedCrossRefGoogle Scholar
  9. 9.
    Johns LC, van Os J: The continuity of psychotic experiences in the general population. Clin Psychol Rev 2001, 21:1125–1141.PubMedCrossRefGoogle Scholar
  10. 10.
    Johns LC, Nazroo JY, Bebbington P, Kuipers E: Occurrence of hallucinatory experiences in a community sample and ethnic variations. Br J Psychiatry 2002, 180:174–178.PubMedCrossRefGoogle Scholar
  11. 11.
    van Os J, Verdoux H, Maurice-Tison S, et al.: Self-reported psychosis-like symptoms and the continuum of psychosis. Soc Psychiatry Psychiatr Epidemiol 1999, 34:459–463.PubMedCrossRefGoogle Scholar
  12. 12.
    Allen P, Freeman D, Johns L, McGuire P: Misattribution of self-generated speech in relation to hallucinatory proneness and delusional ideation in healthy volunteers. Schizophr Res 2006, 84:281–288.PubMedCrossRefGoogle Scholar
  13. 13.
    Freeman D: Suspicious minds: the psychology of persecutory delusions. Clin Psychol Rev 2007, 27:425–457.PubMedCrossRefGoogle Scholar
  14. 14.
    Tien AY: Distributions of hallucinations in the population. Soc Psychiatry Psychiatr Epidemiol 1991, 26:287–292.PubMedCrossRefGoogle Scholar
  15. 15.
    Kendler KS, Gallagher TJ, Abelson JM, Kessler RC: Lifetime prevalence, demographic risk factors, and diagnostic validity of nonaffective psychosis as assessed in a US community sample. The National Comorbidity Survey. Arch Gen Psychiatry 1996, 53:1022–1031.PubMedGoogle Scholar
  16. 16.
    Ohayon MM: Prevalence of hallucinations and their pathological associations in the general population. Psychiatry Res 2000, 97:153–164.PubMedCrossRefGoogle Scholar
  17. 17.
    Claridge G, McCreery C, Mason O, et al.: The factor structure of ’schizotypal’ traits: a large replication study. Br J Clin Psychol 1996, 35:103–115.PubMedGoogle Scholar
  18. 18.
    van Os J, Hanssen M, Bijl RV, Ravelli A: Strauss (1969) revisited: a psychosis continuum in the general population? Schizophr Res 2000, 45:11–20.PubMedCrossRefGoogle Scholar
  19. 19.
    van der Werf M, van Boxtel M, Verhey F, et al.: Mild hearing impairment and psychotic experiences in a normal aging population. Schizophr Res 2007, 94:180–186.PubMedCrossRefGoogle Scholar
  20. 20.
    Stefanis NC, Hanssen M, Smirnis NK, et al.: Evidence that three dimensions of psychosis have a distribution in the general population. Psychol Med 2002, 32:347–358.PubMedCrossRefGoogle Scholar
  21. 21.
    Cohen CJ, Magai C, Yaffee R, Walcott-Brown L: Racial differences in paranoid ideation and psychoses in an older urban population. Am J Psychiatry 2004, 161:864–871.PubMedCrossRefGoogle Scholar
  22. 22.
    Compton MT, Kaslow NJ: Self-reported psychotic symptoms predict impulsivity among African-American patients in an urban non-psychiatric medical setting. Psychiatry Res 2005, 135:35–44.PubMedCrossRefGoogle Scholar
  23. 23.
    Compton MT, Carter T, Kryda A, et al.: The impact of psychoticism on perceived hassles, depression, hostility, and hopelessness in non-psychiatric African Americans. Psychiatry Res 2008, 159:215–225.PubMedCrossRefGoogle Scholar
  24. 24.
    Lincoln TM: Relevant dimensions of delusions: continuing the continuum versus category debate. Schizophr Res 2007, 93:211–220.PubMedCrossRefGoogle Scholar
  25. 25.
    Rado S: Dynamics and classification in disordered behavior. Am J Psychiatry 1953, 110:406–416.PubMedGoogle Scholar
  26. 26.
    Kendler KS: Diagnostic approaches to schizotypal personality disorder: a historical perspective. Schizophr Bull 1985, 11:538–553.PubMedGoogle Scholar
  27. 27.
    Meehl P: Schizotaxia, schizotypy, schizophrenia. Am Psychol 1962, 17:827–838.CrossRefGoogle Scholar
  28. 28.
    Fossati A, Raine A, Carretta I, et al.: The three-factor model of schizotypal personality: invariance across age and gender. Pers Individ Dif 2003, 35:1007–1019.CrossRefGoogle Scholar
  29. 29.
    Meehl P: Schizotaxia revisited. Arch Gen Psychiatry 1989, 152:935–944.Google Scholar
  30. 30.
    Tsuang MT, Stone WS, Tarbox SI, Faraone SV: An integration of schizophrenia with schizotypy: identification of schizotaxia and implications for research on treatment and prevention. Schizophr Res 2002, 54:169–175.PubMedCrossRefGoogle Scholar
  31. 31.
    Raine A, Lencz T: Conceptual and theoretical issues in schizotypal personality research. In Schizotypal Personality. Edited by Raine A, Lencz T, Mednick SA. New York: Cambridge University Press; 1995:3–17.Google Scholar
  32. 32.
    Kendler KS, McGuire M, Gruenberg AM, Walsh D: Schizotypal symptoms and signs in the Roscommon family study. Arch Gen Psychiatry 1995, 52:296–303.PubMedGoogle Scholar
  33. 33.
    Gottesmann II: Schizophrenia Genesis: The Origins of Madness. New York: W.H. Freeman and Co.; 1991.Google Scholar
  34. 34.
    Eaton WW, Chen CY: Epidemiology. In The American Psychiatric Publishing Textbook of Schizophrenia. Edited by Lieberman JA, Stroup TS, Perkins DO. Washington, DC: American Psychiatric Publishing; 2006:17–37.Google Scholar
  35. 35.
    Mellor CS: First rank symptoms of schizophrenia. Br J Psychiatry 1970, 117:15–23.PubMedGoogle Scholar
  36. 36.
    Kraemer HC, Noda A, O’Hara R: Categorical versus dimensional approaches to diagnosis: methodological challenges. J Psychiatr Res 2004, 38:17–25.PubMedCrossRefGoogle Scholar
  37. 37.
    Trull TJ, Durrett CA: Categorical and dimensional models of personality disorders. Ann Rev Clin Psychol 2005, 1:355–380.CrossRefGoogle Scholar
  38. 38.
    Kendell R, Jablensky A: Distinguishing between the validity and utility of psychiatric diagnoses. Am J Psychiatry 2003, 160:4–12.PubMedCrossRefGoogle Scholar
  39. 39.
    Craddock N, Owen MJ: The beginning of the end for the Kraepelinian dichotomy. Br J Psychiatry 2005, 186:364–366.PubMedCrossRefGoogle Scholar
  40. 40.
    Mellsop GW, Menkes DB, El-Badri SM: Classification in psychiatry: does it deliver in schizophrenia and depression? Int J Ment Health Syst 2007, 1:7.PubMedCrossRefGoogle Scholar
  41. 41.
    Dutta R, Greene T, Addington J, et al.: Biological, life course, and cross-cultural studies all point toward the value of dimensional and developmental ratings in the classification of psychosis. Schizophr Bull 2007, 33:868–876.PubMedCrossRefGoogle Scholar
  42. 42.
    Peralta V, Cuesta MJ: A dimensional and categorical architecture for the classification of psychotic disorders. World Psychiatry 2007, 6:100–101.PubMedGoogle Scholar
  43. 43.
    Widiger TA, Samuel DB: Diagnostic categories or dimensions? A question for the Diagnostic and Statistical Manual of Mental Disorders—Fifth Edition. J Abnorm Psychol 2005, 114:494–504.PubMedCrossRefGoogle Scholar
  44. 44.
    Robins E, Guze SB: Establishment of diagnostic validity in psychiatric illness: its application to schizophrenia. Am J Psychiatry 1970, 126:983–986.PubMedGoogle Scholar
  45. 45.
    Krueger RF, Watson D, Barlow DH: Toward a dimensionally based taxonomy of psychopathology. J Abnorm Psychol 2005, 114:491–493.PubMedCrossRefGoogle Scholar
  46. 46.
    Esterberg ML, Trotman HD, Brasfield J, et al.: Childhood and current autistic features in adolescents with schizotypal personality disorder. Schizophr Res 2008, 104:265–273.PubMedCrossRefGoogle Scholar
  47. 47.
    Peralta V, Cuesta MJ, Giraldo C, et al.: Classifying psychotic disorders: issues regarding categorical vs. dimensional approaches and time frame to assess symptoms. Eur Arch Psychiatry Clin Neurosci 2002, 252:12–18.PubMedGoogle Scholar
  48. 48.
    Rosenman S, Korten A, Medway J, Evans M: Dimensional vs. categorical diagnoses in psychosis. Acta Psychiatr Scand 2003, 107:378–384.PubMedCrossRefGoogle Scholar
  49. 49.
    van Os J, Gilvarry C, Bale R, et al.: A comparison of the utility of dimensional and categorical representations of psychosis. Psychol Med 1999, 29:595–606.PubMedCrossRefGoogle Scholar
  50. 50.
    van Os J, Fahy T, Jones P, et al.: Psychopathological syndromes in the functional psychoses: associations with course and outcome. Psychol Med 1996, 26:203–208.CrossRefGoogle Scholar

Copyright information

© Current Medicine Group, LLC 2009

Authors and Affiliations

  1. 1.Department of Psychiatry and Behavioral SciencesEmory University School of MedicineAtlantaUSA

Personalised recommendations