C o m o r b i d i t y for D i s r u p t i v e B e h a v i o r D i s o r d e r s in P s y c h i a t r i c a l l y H o s p i t a l i z e d C h i l d r e n Stephen M. Soltys, MD Javad H. Kashani, MD Alison C. Dandoy, MS Alzira F. Vaidya, MD John C. Reid, PhD University of Missouri-Columbia
ABSTRACT: A variety of instruments were used to compare six groups of inpatient children: pure attention deficit disorder with hyperactivity (ADDH), pure conduct disorder (CD), pure oppositional defiant disorder (OD), ADDH + CD, and ADDH + OD, and a clinical control group who had no DBD diagnosis. Children with ADDH and CD or OD exhibited a greater degree of psychopathology. Children with CD and OD were more similar than different, indicating that perhaps a continuum of pathology exists between these diagnostic classifications. KEY WORDS: Disruptive Behavior Disorders; comorbidity; Attention Deficit Disorder with Hyperactivity.
The DSM-III-R diagnostic entity, Attention Deficit Hyperactivity Disorder (ADHD) has been used as a diagnostic category for many years under many different names--minimal brain dysfunction, hyperactivity and attention deficit disorder with hyperactivity (ADDH). Much disagreement exists concerning its relationship with other disorders of conduct. 1,5Such controversy has arisen primarily from recognition of the high degree of overlap between ADDH and other disorders, especially conduct disorder (CD). 3,4 One of the major changes in the DSM-III-R 5 classification scheme for childhood psychiatric disorders was the creation of the category Disruptive Behavior Disorders (DBD). This category actually comprises three disorders: Attention Deficit Hyperactivity Disorder (ADHD), Conduct Disorder (CD), and Oppositional Defiant Disorder (OD). The Received June 10, 1992; For Revision July 28, 1992; Accepted August 15, 1992. Reprints requests should be sent to Stephen M. Soltys, MD, Department of Psychiatry, University of Missouri-Columbia, 3 Hospital Drive, Columbia, MO 65201. Child Psychiatry and Human Development, Vol. 23(2), Winter 1992 9 1992 Human Sciences Press, Inc.
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DSM-III-R notes that evaluations of this new diagnostic classification have shown that symptoms of ADHD co-vary to a high degree with those of CD or OD. The ongoing debate regarding whether ADHD and CD are indeed distinct entities has led to many factor analytic studies designed to explore classification issues. Overall, these studies indicate that these two disorders have at least partially overlapping but independent behavioral dimensions, and that when subgroups are examined, differences emerge2 Mixed (ADHD/CD) children have more aggressive, impulsive, and antisocial behavior whereas pure ADHD children have shorter attention spans and exhibit more academic and cognitive difficulties. Other investigators have expressed doubts about the distinctiveness of OD from the other disruptive behavior disorders. Ferguson and Rapoport 7 suggested that OD be used instead of ADD, while other results s,9 support the view that OD may be a milder form of CD. In fact, a few researchers have chosen to categorize children as "CD/ Oppositionar' when studying the prevalence of psychiatric disorders in epidemiologic samples. 1~ Many investigations of a specific disruptive behavior disorder provide descriptive data on the proportion of subjects who have a concurrent disruptive behavior disorder diagnosis, but there is a dearth of literature addressing the high comorbidity of ADHD and CD. Since estimates of the overlap between these two disorders have ranged from 41% to 75%, 12obviously a clinical sample of ADHD will contain a significant number of children with CD. The situation is likely to be similar with ADHD and OD. Hence, any symptom associated with one disruptive behavior disorder could be mistakenly attributed to another if overlapping children are not distinguished. The importance of controlling for and separately analyzing attention deficit disorder patients with a concurrent diagnosis of conduct disorder was underscored in a recent study by Bowden et al. 13These researchers examined platelet monamine oxidase (MAO) and plasma dopamine-B-hydroxylase (DBH) activity in three groups of boys: ADHD, ADHD + CD-Undersocialized, and healthy controls. Low activity levels of DBH and MAO have been associated with greater impulsivity and conflicts with authorities. Results showed that MAO and DBH activity was lower in ADHD + CD-Undersocialized boys than in those boys who had only ADHD. Furthermore, DBH activity was lower in ADHD § CD-Undersocialized than in controls. However, for
Stephen M. Soltys et al.
89
the full group of ADHD children there were no differences in DBH activity levels when compared with the control group of healthy boys. Bowden et al. 1~ concluded that decreased DBH activity levels were associated only with CD-Undersocialized and that future biological studies should take comorbidity into account during analysis. The effects of comorbidity were also recognized in a study focusing on the psychopathology in the parents of children with CD and ADDH. 14 This investigation (an improved replication of a study by Stewart et al. 15) provided strong support for the view that CD and ADDH are separate disorders by virtue of differing patterns of familial transmission. In this follow-up study, Lahey et al. 14also found that ADDH was not associated with the same antisocial spectrum of parental illness as was CD. In fact, they found no association between ADDH and parental psychopathology. However, fathers of children with both ADDH and CD (which is associated with greater aggression than CD alone) were more likely to have a history of aggression and imprisonment. These results confirm previous findings that CD but not ADDH is linked to parental psychopathology, thus providing a basis for clearly distinguishing the two disorders. Hence, controlling for comorbidity is critical in order to accurately measure psychopathology. The present study furthers our knowledge of comorbidity among the disruptive behavior disorders by studying a clinical population of 100 children admitted to a children's psychiatric inpatient unit. As would be expected in an inpatient sample, there may be a greater degree of comorbidity due to referral bias as compared to a community or a clinic sample. However, we improve upon previous studies (e-g-'1~ by analyzing the disruptive behavior disorders individually instead of grouping them into general categories such as "CD/Oppositional". By separating children with disruptive behavior disorders into subgroups (pure ADDH, ADDH + CD, ADDH + OD, pure CD and pure OD), we specifically hope to ascertain any differences within subgroups on a variety of instruments, taking multiple diagnoses into account. The instruments chosen will provide data on a variety of characteristics--self-esteem, personality, anxiety, and temperament-to obtain a global picture of the degree of psychopathology within the child. A comparison between the various subgroups can then be performed to assess differences in behavior based on overlapping behavior disorder diagnoses.
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Method
Subjects and Procedure The sample consisted of 100 children admitted to an inpatient child psychiatry service within a community mental health center (CMHC). To obtain our sample, 155 children consecutively admitted to the inpatient setting were evaluated. Subjects were then excluded from the sample either on the basis of age (outside the 7-12 year age group) or a Full Scale WISC-R score below 70. After 100 subjects had qualified for the study, the investigation was stopped. Of the 100 subjects, 73 were males and 27 were females, aged 7 to 12 years. Ninety-one percent were caucasian and 9% blacks. (The catchment area was 90% caucasian, 8% black, 1% Oriental, and 1% Hispanic.) Family social class, calculated by the Hollingshead and Redlich Index, TM yielded the following breakdown: Class V (10%), Class IV (34%), Class III (50%), Class II (5%), and Class I (5%). Children were interviewed during the first week of admission to the inpatient unit by a Ph.D. candidate in Clinical Psychology trained to administer the DICA. The DICA was used as the basis for diagnostic grouping of the children because of its standardized administration as opposed to clinical diagnoses which may vary between clinicians. Because no diagnostic instrument existed at the beginning of the study that used DSM-III-R criteria to investigate inter-relationships between disruptive behavior disorders, we used the DICA which is based on DSM-III criteria. Also, all parent(s) were interviewed and completed self-report questionnaires.
Distinction Between Groups According to DSM-III criteria, a child may have a diagnosis of Attention Deficit Disorder with Hyperactivity (ADDH) and a diagnosis of either Conduct Disorder (CD) or Oppositional Defiant Disorder (OD). However, no subject can receive a diagnosis of both Conduct Disorder and Oppositional Deftant Disorder, which are mutually exclusive. To assess the effects of comorbidity within our sample, the three primary diagnoses of ADDH, CD, and OD were separated into five subcategories. These include: 1. Pure ADDH (n = 8)--no concurrent diagnosis of CD or OD 2. Pure CD (n = 8)--no concurrent diagnosis of ADDH 3. Pure OD (n = 18)--no concurrent diagnosis of ADDH 4. ADDH + CD (n= 16) 5. ADDH + OD (n=21) These groups were then compared to a clinical control population (n--29) of all patients hospitalized on the inpatient unit who did not have a disruptive disorder diagnosis (e.g., did not have the diagnosis of ADDH, CD, or OD) on the DICA. Eight children in the clinical control group received a DICA diagnosis of Anxiety disorder, three had depression, and nine had an enuresis/ encopresis DICA diagnosis. Nine children in the clinical control group did not
Stephen M. Soltys et al.
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receive a DICA diagnosis but had one or more diagnosis based on team assessment.
Instruments For obtaining DSM-III diagnosis: Diagnostic Interview for Children and Adolescents (DICA). The DICA 17is a structured diagnostic interview keyed to DSM-III criteria. This instrument assesses common psychiatric disorders in children and adolescents. Reliability and validity are satisfactory27,~8 The other inventories chosen were selected to provide measures on a wide variety of areas as we looked for possible similarities and distinguishing characteristics between the various disruptive behavior disorders. Piers-Harris Children's Self-Concept Scale. The Piers-Harris scale, ~9 "The Way I Feel About Myself', is an 80-item (yes/no) self-report questionnaire developed for a wide age range of children. The six subscales are: Behavior, Intellectual and School Status, Physical Appearance, Anxiety, Popularity, and Happiness and Satisfaction. Validity and reliability of this scale are described in the Piers-Harris manual. Revised Children's Manifest Anxiety Scale (RCMAS). The RCMAS ~~ is a 37-item true/false self-rating scale on anxiety. Five factors comprise the RCMAS: Physiological, Worry/oversensitivity, Concentration, a lie score, and an anxiety score. Its high reliability and validity have been well established.20.21 Dimensions of Temperament Survey (DOTS). The DOTS 22 is an 89-item dichotomous questionnaire in three forms. In the present study it reveals responses by the child about the child. Nine dimensions of temperament derived from the New York Longitudinal Study are identified with this scale. Reliability and validity of these categories varies from low to moderate. 2~ Life Events Checklist (LEC). The LEC 23 identifies and assesses a range of positive and negative life events that have occurred in the past year as well as their perceived impact on the individual. Children rate events on a 4-point scale with positive and negative change events scored separately. Test-retest reliability, interrater reliability, and validity data have been reported. ~3,24,~5 Personality Inventory for Children. The PIC 28 is a true/false questionnaire completed by the parent about the child. Twelve clinical and four validity scales comprise the 16 scales of the PIC. Lachar et al. 27 describe its internal consistency, validity, and test-retest reliability of the factor scales.
Statistical Analyses Following the breakdown of the sample into subpopulations, analyses performed were either chi square (Yates corrected) tests for dichotomous data or Mann-Whitney U tests for interval data. All were two-tailed tests. The Bonferroni probability levels for the PIC, Piers-Harris, and DOT are .004, .008, and .005 respectively. However, we have reported only the obtained probabilities.
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Results
Demographic characteristics of the subgroups show that the ADDH + CD and the ADDH + OD groups had a higher proportion of males than did the pure groups or the clinical control group, although this difference was not significant. Analysis of age, socioeconomic class, and race failed to show any significant differences between various groups. The total number of DICA diagnoses in each group was examined. The clinical control population had 0.7 DICA diagnosis (Dx) per patient. This compares with a markedly higher number in any patient with CD or OD, especially if they are comorbid with ADDH. There were 3.8 Dx per patient in the ADDH § CD group, 3.2 Dx per patient for ADDH + OD, 2 Dx per patient for pure CD, and 1.9 Dx per patient for pure OD. The most common additional diagnoses for children with OD or CD were anxiety disorders, elimination disorders, and depression. In contrast, not one of the children with pure ADDH had a DICA diagnosis in addition to ADDH. Differences between the subgroups of disruptive behavior disorders and children in the clinical control group are documented in Table 1. Children in all five subgroups had significantly more negative life events compared to the clinical control group. It appears that children in the mixed groups of CD + ADDH and OD § ADDH have a greater degree of psychopathology as revealed through (1) the instrument results (Table 1), and (2) the greater number of DICA diagnoses than do children in the pure CD, pure ADDH, and pure OD group. This observation is not surprising since children with multiple disorders are considered to have greater psychopathology than children with fewer disorders. There are few differences between children with CD and OD. More specifically, the only significant difference between the CD + ADDH groups and the OD + ADDH group is the presence of fewer negative life events in the latter group. Similarly, the only difference between the pure CD group and the pure OD group was the significantly lower threshold scores on the DOT in pure OD children. The overall similarity of these groups on every other measure supports the view that OD may represent a milder form of CD. Given the degree of behavior disturbance of children referred to our unit, it was somewhat surprising to find that children in the pure CD group significantly differed from the clinical control group on only three measures, showing more negative life events, lower behavior
Stephen M. Soltys et al.
93
scores on the Piers-Harris, and higher depression scores on the PIC. Significantly higher PIC depression scores were associated both with pure CD children and those in the CD + ADDH group, while lower happiness but not depression scores were associated with the pure OD and OD + ADDH groups. Pure ADDH, pure OD, and OD + ADDH children also had higher PIC depression scores compared to the hospital controls but not to the p
ABSTRACT: A variety of instruments were used to compare six groups of inpatient children: pure attention deficit disorder with hyperactivity (ADDH), pure conduct disorder (CD), pure oppositional defiant disorder (OD), ADDH + CD, and ADDH + OD, and a clinical control group who had no DBD diagnosis. Children with ADDH and CD or OD exhibited a greater degree of psychopathology. Children with CD and OD were more similar than different, indicating that perhaps a continuum of pathology exists between these diagnostic classifications. KEY WORDS: Disruptive Behavior Disorders; comorbidity; Attention Deficit Disorder with Hyperactivity.
The DSM-III-R diagnostic entity, Attention Deficit Hyperactivity Disorder (ADHD) has been used as a diagnostic category for many years under many different names--minimal brain dysfunction, hyperactivity and attention deficit disorder with hyperactivity (ADDH). Much disagreement exists concerning its relationship with other disorders of conduct. 1,5Such controversy has arisen primarily from recognition of the high degree of overlap between ADDH and other disorders, especially conduct disorder (CD). 3,4 One of the major changes in the DSM-III-R 5 classification scheme for childhood psychiatric disorders was the creation of the category Disruptive Behavior Disorders (DBD). This category actually comprises three disorders: Attention Deficit Hyperactivity Disorder (ADHD), Conduct Disorder (CD), and Oppositional Defiant Disorder (OD). The Received June 10, 1992; For Revision July 28, 1992; Accepted August 15, 1992. Reprints requests should be sent to Stephen M. Soltys, MD, Department of Psychiatry, University of Missouri-Columbia, 3 Hospital Drive, Columbia, MO 65201. Child Psychiatry and Human Development, Vol. 23(2), Winter 1992 9 1992 Human Sciences Press, Inc.
87
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Child Psychiatry and Human Development
DSM-III-R notes that evaluations of this new diagnostic classification have shown that symptoms of ADHD co-vary to a high degree with those of CD or OD. The ongoing debate regarding whether ADHD and CD are indeed distinct entities has led to many factor analytic studies designed to explore classification issues. Overall, these studies indicate that these two disorders have at least partially overlapping but independent behavioral dimensions, and that when subgroups are examined, differences emerge2 Mixed (ADHD/CD) children have more aggressive, impulsive, and antisocial behavior whereas pure ADHD children have shorter attention spans and exhibit more academic and cognitive difficulties. Other investigators have expressed doubts about the distinctiveness of OD from the other disruptive behavior disorders. Ferguson and Rapoport 7 suggested that OD be used instead of ADD, while other results s,9 support the view that OD may be a milder form of CD. In fact, a few researchers have chosen to categorize children as "CD/ Oppositionar' when studying the prevalence of psychiatric disorders in epidemiologic samples. 1~ Many investigations of a specific disruptive behavior disorder provide descriptive data on the proportion of subjects who have a concurrent disruptive behavior disorder diagnosis, but there is a dearth of literature addressing the high comorbidity of ADHD and CD. Since estimates of the overlap between these two disorders have ranged from 41% to 75%, 12obviously a clinical sample of ADHD will contain a significant number of children with CD. The situation is likely to be similar with ADHD and OD. Hence, any symptom associated with one disruptive behavior disorder could be mistakenly attributed to another if overlapping children are not distinguished. The importance of controlling for and separately analyzing attention deficit disorder patients with a concurrent diagnosis of conduct disorder was underscored in a recent study by Bowden et al. 13These researchers examined platelet monamine oxidase (MAO) and plasma dopamine-B-hydroxylase (DBH) activity in three groups of boys: ADHD, ADHD + CD-Undersocialized, and healthy controls. Low activity levels of DBH and MAO have been associated with greater impulsivity and conflicts with authorities. Results showed that MAO and DBH activity was lower in ADHD + CD-Undersocialized boys than in those boys who had only ADHD. Furthermore, DBH activity was lower in ADHD § CD-Undersocialized than in controls. However, for
Stephen M. Soltys et al.
89
the full group of ADHD children there were no differences in DBH activity levels when compared with the control group of healthy boys. Bowden et al. 1~ concluded that decreased DBH activity levels were associated only with CD-Undersocialized and that future biological studies should take comorbidity into account during analysis. The effects of comorbidity were also recognized in a study focusing on the psychopathology in the parents of children with CD and ADDH. 14 This investigation (an improved replication of a study by Stewart et al. 15) provided strong support for the view that CD and ADDH are separate disorders by virtue of differing patterns of familial transmission. In this follow-up study, Lahey et al. 14also found that ADDH was not associated with the same antisocial spectrum of parental illness as was CD. In fact, they found no association between ADDH and parental psychopathology. However, fathers of children with both ADDH and CD (which is associated with greater aggression than CD alone) were more likely to have a history of aggression and imprisonment. These results confirm previous findings that CD but not ADDH is linked to parental psychopathology, thus providing a basis for clearly distinguishing the two disorders. Hence, controlling for comorbidity is critical in order to accurately measure psychopathology. The present study furthers our knowledge of comorbidity among the disruptive behavior disorders by studying a clinical population of 100 children admitted to a children's psychiatric inpatient unit. As would be expected in an inpatient sample, there may be a greater degree of comorbidity due to referral bias as compared to a community or a clinic sample. However, we improve upon previous studies (e-g-'1~ by analyzing the disruptive behavior disorders individually instead of grouping them into general categories such as "CD/Oppositional". By separating children with disruptive behavior disorders into subgroups (pure ADDH, ADDH + CD, ADDH + OD, pure CD and pure OD), we specifically hope to ascertain any differences within subgroups on a variety of instruments, taking multiple diagnoses into account. The instruments chosen will provide data on a variety of characteristics--self-esteem, personality, anxiety, and temperament-to obtain a global picture of the degree of psychopathology within the child. A comparison between the various subgroups can then be performed to assess differences in behavior based on overlapping behavior disorder diagnoses.
90
Child Psychiatry and Human Development
Method
Subjects and Procedure The sample consisted of 100 children admitted to an inpatient child psychiatry service within a community mental health center (CMHC). To obtain our sample, 155 children consecutively admitted to the inpatient setting were evaluated. Subjects were then excluded from the sample either on the basis of age (outside the 7-12 year age group) or a Full Scale WISC-R score below 70. After 100 subjects had qualified for the study, the investigation was stopped. Of the 100 subjects, 73 were males and 27 were females, aged 7 to 12 years. Ninety-one percent were caucasian and 9% blacks. (The catchment area was 90% caucasian, 8% black, 1% Oriental, and 1% Hispanic.) Family social class, calculated by the Hollingshead and Redlich Index, TM yielded the following breakdown: Class V (10%), Class IV (34%), Class III (50%), Class II (5%), and Class I (5%). Children were interviewed during the first week of admission to the inpatient unit by a Ph.D. candidate in Clinical Psychology trained to administer the DICA. The DICA was used as the basis for diagnostic grouping of the children because of its standardized administration as opposed to clinical diagnoses which may vary between clinicians. Because no diagnostic instrument existed at the beginning of the study that used DSM-III-R criteria to investigate inter-relationships between disruptive behavior disorders, we used the DICA which is based on DSM-III criteria. Also, all parent(s) were interviewed and completed self-report questionnaires.
Distinction Between Groups According to DSM-III criteria, a child may have a diagnosis of Attention Deficit Disorder with Hyperactivity (ADDH) and a diagnosis of either Conduct Disorder (CD) or Oppositional Defiant Disorder (OD). However, no subject can receive a diagnosis of both Conduct Disorder and Oppositional Deftant Disorder, which are mutually exclusive. To assess the effects of comorbidity within our sample, the three primary diagnoses of ADDH, CD, and OD were separated into five subcategories. These include: 1. Pure ADDH (n = 8)--no concurrent diagnosis of CD or OD 2. Pure CD (n = 8)--no concurrent diagnosis of ADDH 3. Pure OD (n = 18)--no concurrent diagnosis of ADDH 4. ADDH + CD (n= 16) 5. ADDH + OD (n=21) These groups were then compared to a clinical control population (n--29) of all patients hospitalized on the inpatient unit who did not have a disruptive disorder diagnosis (e.g., did not have the diagnosis of ADDH, CD, or OD) on the DICA. Eight children in the clinical control group received a DICA diagnosis of Anxiety disorder, three had depression, and nine had an enuresis/ encopresis DICA diagnosis. Nine children in the clinical control group did not
Stephen M. Soltys et al.
91
receive a DICA diagnosis but had one or more diagnosis based on team assessment.
Instruments For obtaining DSM-III diagnosis: Diagnostic Interview for Children and Adolescents (DICA). The DICA 17is a structured diagnostic interview keyed to DSM-III criteria. This instrument assesses common psychiatric disorders in children and adolescents. Reliability and validity are satisfactory27,~8 The other inventories chosen were selected to provide measures on a wide variety of areas as we looked for possible similarities and distinguishing characteristics between the various disruptive behavior disorders. Piers-Harris Children's Self-Concept Scale. The Piers-Harris scale, ~9 "The Way I Feel About Myself', is an 80-item (yes/no) self-report questionnaire developed for a wide age range of children. The six subscales are: Behavior, Intellectual and School Status, Physical Appearance, Anxiety, Popularity, and Happiness and Satisfaction. Validity and reliability of this scale are described in the Piers-Harris manual. Revised Children's Manifest Anxiety Scale (RCMAS). The RCMAS ~~ is a 37-item true/false self-rating scale on anxiety. Five factors comprise the RCMAS: Physiological, Worry/oversensitivity, Concentration, a lie score, and an anxiety score. Its high reliability and validity have been well established.20.21 Dimensions of Temperament Survey (DOTS). The DOTS 22 is an 89-item dichotomous questionnaire in three forms. In the present study it reveals responses by the child about the child. Nine dimensions of temperament derived from the New York Longitudinal Study are identified with this scale. Reliability and validity of these categories varies from low to moderate. 2~ Life Events Checklist (LEC). The LEC 23 identifies and assesses a range of positive and negative life events that have occurred in the past year as well as their perceived impact on the individual. Children rate events on a 4-point scale with positive and negative change events scored separately. Test-retest reliability, interrater reliability, and validity data have been reported. ~3,24,~5 Personality Inventory for Children. The PIC 28 is a true/false questionnaire completed by the parent about the child. Twelve clinical and four validity scales comprise the 16 scales of the PIC. Lachar et al. 27 describe its internal consistency, validity, and test-retest reliability of the factor scales.
Statistical Analyses Following the breakdown of the sample into subpopulations, analyses performed were either chi square (Yates corrected) tests for dichotomous data or Mann-Whitney U tests for interval data. All were two-tailed tests. The Bonferroni probability levels for the PIC, Piers-Harris, and DOT are .004, .008, and .005 respectively. However, we have reported only the obtained probabilities.
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Child Psychiatry and Human Development
Results
Demographic characteristics of the subgroups show that the ADDH + CD and the ADDH + OD groups had a higher proportion of males than did the pure groups or the clinical control group, although this difference was not significant. Analysis of age, socioeconomic class, and race failed to show any significant differences between various groups. The total number of DICA diagnoses in each group was examined. The clinical control population had 0.7 DICA diagnosis (Dx) per patient. This compares with a markedly higher number in any patient with CD or OD, especially if they are comorbid with ADDH. There were 3.8 Dx per patient in the ADDH § CD group, 3.2 Dx per patient for ADDH + OD, 2 Dx per patient for pure CD, and 1.9 Dx per patient for pure OD. The most common additional diagnoses for children with OD or CD were anxiety disorders, elimination disorders, and depression. In contrast, not one of the children with pure ADDH had a DICA diagnosis in addition to ADDH. Differences between the subgroups of disruptive behavior disorders and children in the clinical control group are documented in Table 1. Children in all five subgroups had significantly more negative life events compared to the clinical control group. It appears that children in the mixed groups of CD + ADDH and OD § ADDH have a greater degree of psychopathology as revealed through (1) the instrument results (Table 1), and (2) the greater number of DICA diagnoses than do children in the pure CD, pure ADDH, and pure OD group. This observation is not surprising since children with multiple disorders are considered to have greater psychopathology than children with fewer disorders. There are few differences between children with CD and OD. More specifically, the only significant difference between the CD + ADDH groups and the OD + ADDH group is the presence of fewer negative life events in the latter group. Similarly, the only difference between the pure CD group and the pure OD group was the significantly lower threshold scores on the DOT in pure OD children. The overall similarity of these groups on every other measure supports the view that OD may represent a milder form of CD. Given the degree of behavior disturbance of children referred to our unit, it was somewhat surprising to find that children in the pure CD group significantly differed from the clinical control group on only three measures, showing more negative life events, lower behavior
Stephen M. Soltys et al.
93
scores on the Piers-Harris, and higher depression scores on the PIC. Significantly higher PIC depression scores were associated both with pure CD children and those in the CD + ADDH group, while lower happiness but not depression scores were associated with the pure OD and OD + ADDH groups. Pure ADDH, pure OD, and OD + ADDH children also had higher PIC depression scores compared to the hospital controls but not to the p
