Clinical Assessment of Child and Adolescent Personality and ...

380CHAPTER 17 Assessment of Attention Deficit Hyperactivitythat the decision to eliminate the subtypesin the DSM-III-R was not consistent withthis body of research.DSM-IV-TRThe DSM-IV-TR definition of ADHD wasdesigned to reflect research findings onboth of these issues (American PsychiatricAssociation, 2000). First, there are twosymptom lists, which closely correspond tothe two dimensions of behavior describedin Table 17.1. Second, the DSM-IV-TRrecognizes the existence of subtypes basedlargely on the presence of hyperactivity.There is an ADHD Predominantly InattentiveType to designate children withproblems of inattention and disorganizationbut without problems of impulsivityand overactivity. In addition, there are theADHD Predominantly Hyperactive Typeand ADHD Combined Type to designatechildren with significant problems ofimpulsivity-hyperactivity, either in isolationfrom or in combination with problemsof inattention and disorganization.While these subtypes seem to match theresearch findings summarized previously,it is important to note that the stability ofthese ADHD subtypes over time is questionable.Specifically, in a sample of 118children with ADHD who were ages 4 to6 at the start of the study, Lahey, Pelham,Loney, Lee, and Wilcutt (2005) reportedthat it was not unusual for children tochange in their subtype of ADHD over the8-year study period. For example, 37% ofchildren with Combined Type and 50% ofthe children with Predominantly InattentiveType met criteria for a different subtypeat least twice during the study period.Children with the Hyperactive Type werethe most likely to shift subtypes, with mostshifting to the Combined Type at somepoint during the study.An inspection of the symptoms includedin the DSM-IV-TR criteria for ADHD (seeTable 17.1) indicate that the individualbehaviors that form the diagnostic criteriafor this disorder are behaviors that arequite common to some degree in normallydeveloping children and adolescents. Thisis one of the issues that has led to seriousconcerns over the potential overdiagnosisof the disorder and concomitant overuse ofstimulant medication to treat it (Angold,Erkanli, Egger, & Costello, 2000; Jensenet al., 1999). There are two critical issuesrelated to these concerns. First, at present,there is little empirical evidence tosupport the concerns about overdiagnosisand overmedication, although clearly thisis a very difficult issue on which to obtaingood data (Jensen et al., 1999). Second, thesymptoms of most childhood disorders,not just ADHD, are not qualitatively differentfrom normal behaviors shown bychildren (e.g., sadness as a symptom ofdepression). This is not to imply that this isnot an important issue in assessment but toillustrate that it is not specific to ADHD.It relates to the important issue raised inChap. 3 that classification systems mustclearly define what parameters are mostimportant for differentiating disordered(i.e., clinically impairing) manifestationsof the symptoms from more normal manifestations.The DSM-IV-TR includes severalsuch parameters for the diagnosis ofADHD, and it is imperative that assessorssystematically assess these parameters toavoid overdiagnosis.The first parameter is the frequency andseverity of the symptoms. The DSM-IV-TRsets six symptoms of either inattention-disorganizationor impulsivity-hyperactivityas the diagnostic threshold for the disorder.This level of severity was chosen basedon evidence that it seemed to designate alevel of symptomology that predictedclinically significant levels of psychosocialimpairment (e.g., poor academic performance,social rejection) for elementaryschool-aged children (Lahey, Applegate,McBurnett, et al., 1994). Using this diagnosticthreshold, 3–7% of children would