Clinical Assessment of Child and Adolescent Personality and ...

54 CHAPTER 3 CLASSIFICATION AND DEVELOPMENTAL PSYCHOPATHOLOGYflaws that make their exclusive use problematic(see Quay, 1986). For example, thedependence of medical model approacheson theory has led to many “disorders” beingcreated with little support from research.Also, the medical model approach, with itsemphasis on qualitative distinction, masksa continuum with normality that seemsmost appropriate for understanding manydimensions of functioning. In contrast,the multivariate approach with its dependenceon statistical analyses in the absenceof clear theory has resulted in syndromesthat are hard to generalize across samplesand with different sets of symptoms. Also,while some psychological phenomena inchildren and adolescents are best conceptualizedon a continuum with normality,there are others that may fit with morequalitative distinctions (e.g., Kagan &Snidman, 1991; Lahey et al., 1990) andare not captured well by the multivariateapproach.As a result, future classificationsshould look towards an integration of theapproaches. For example, clinical diagnosescan be improved by conducting multivariateanalyses to see if the covariationof symptoms for the diagnosis is supported(e.g., Frick, et al., 1993; Lahey et al.,2004). However, there are other ways inwhich the correspondence between statisticallyderived syndromes and the clinicallyderived diagnoses can be explicitly tested(e.g., Eiraldi, Power, Karustis, & Goldstein,2000), thereby improving the validityof both the approaches and leading to classificationsystems that accommodate thediverse nature of psychological constructs.In the following section, we provide anoverview of one of the most commonlyused classification systems, the Diagnosticand Statistical Manual of Mental Disorders,which is published by the American PsychiatricAssociation. Although initially thissystem of classification was based largelyon a medical model system of classification,more recent revisions have attemptedto capture the best characteristics of thetwo major classification approaches.Diagnostic and StatisticalManual of Mental Disorders,Fourth Edition (DSM-IV; APA,1994 & DSM-IVTR; APA, 2000)The DSM approach to defining psychiatricdisorders has undergone dramaticchanges in its many revisions since its firstpublication in 1952. The biggest changecame with the publication of its thirdrevision in 1980. In the first two editions,the definition of disorder was clearlybased on a medical model approach toclassification. The definition assumedan underlying pathological core, and theconceptualization of the core was largelybased on psychodynamic theory. In thethird edition, there was an explicit switchfrom a medical model view of disordersand a dependence on the psychodynamictheory. In the third and subsequent editions,a functional approach of viewingdisorders was used in which mentaldisorders were defined as “a clinicallysignificant behavioral or psychologicalsyndrome or pattern that occurs in anindividual and is typically associated withpresent distress (e.g., a painful symptom)or disability (i.e., impairment in one ormore important areas of functioning), orwith a significantly increased risk of suffering,death, pain, disability, or importantloss of freedom.” (p. xxxi, AmericanPsychiatric Association, 2000).Another major change in the thirdedition, also maintained in subsequentrevisions, is an increase in the level ofspecificity with which disorders aredefined. In the first two editions of themanual, disorders were often poorlydefined, leading to problems of obtaininghigh levels of reliability in the diagnosticclassifications (Spitzer & Cantwell,1980). In contrast, later revisions include