The Occurrence of Behavior Disorders in Children: The Interdependence of Attention Deficit Disorder and Conduct Disorder

The Occurrence of Behavior Disorders in Children: The Interdependence of Attention Deficit Disorder and Conduct Disorder STEVEN K. SHAPIRO, B.A., AND BARRY D. GARFINKEL, M.D., F.R.C.P.(C) A nonreferred elementary school population of 315 children participated in a screening for behavioral problems. The prevalence of inattentive-overactive symptoms suggestive of Attention Deficit Disorder (ADD) was determined to be 2.3%; 3.6% of the children had aggressive/oppositional symptoms suggestive of Conduct Disorder (CD). Another 3.0% showed both ADD and CD symptoms. Index children comprise 8.9% of the school population and were more likely to come from broken homes and had more remedial education. They also had higher scores on the ADD Interview (DICA) and were more impulsive and disorganized on a computerized attentional battery. There were no symptoms or characteristics that differentiated the inattentive-overactive (ADD) from the aggressive/oppositional (CD) child. Multivariate statistical techniques indicated a different relative importance of individual symptoms in the two groups. These results suggest the interdepencence of symptoms commonly associated with ADD and CD diagnoses. Journal of the American Academy of Child Psychiatry, 25, 6:809-819, 1986.

Epidemiological studies have revealed discrepancies both in prevalence rates and in clinical criteria for various psychiatric disorders. Attention Deficit Disorder (ADD) is a controversial example of this disagreement. Studies surveying incidence rates within clinic populations have yielded striking variability. Nylander (1979), reviewing 2364 cases from a Stockholm child guidance clinic showed complaints of hyperactivity and disturbed concentration in 27% of boys and in 16% of girls. Safer and Allen (1976) found 40% of their cases at an American child guidance clinic met criteria for Hyperactivity. Thorley (1984), however, noted a 1.24% incidence rate for the Hyperkinetic Syndrome (lCD-9) at the Maudsley Children's Clinic. Surveys using samples of nonreferred children have also shown variability both in symptom frequency and in diagnostic prevalence. Earls (1980), interviewing parents of 3-year-old preschoolers, found overactivity to be a problem in 4% of the boys and none of the girls; impaired concentration was found in 8% of the boys and 4.3% of the girls. An empirically derived teacher questionnaire used to assess Minimal Brain Dysfunction (MHD) in 3448 urban Swedish preschoolers (Gillberg et al., 1982) identified 1.2% as having

severe attention deficits, neurological or perceptual problems with an additional 6% showing less severe forms of these problems. Using a similar approach, Kohler (1973) estimated that 2.1% of 4-year-old Swedish children met MBD criteria. Assessing 1753 children from kindergarten through second grade with the Quay-Peterson checklist (1967) Werry and Quay (1971) showed boys to have more inattentive/overactive symptoms than girls. Prevalence rates for these behaviors ranged from 25 to 58% for boys and 10 to 32% for girls. Gorin (1973), with a 27% participation rate of 7-year-olds in Connecticut schools, reported a 5% prevalence rate of the Hyperkinetic Syndrome. In this study, the teacher was asked to determine whether each child met criteria for significant inattention and hyperactive problems. Crucial major metropolitan school systems did not participate and sample bias may have affected the prevalence rates. Additionally, using the teacher as the diagnostician instead of symptom raters presents the problem of diagnostic validity. Using various cognitive and perceptual instruments as well as behavioral ratings, Korhonen and Sillanpaa (1976) observed a prevalence rate of 7-10% in 208 10year-olds: an additional 16% showed "MBD-like" behavior. Older elementary school children have been studied by Rutter et al. (1970). Fewer than 1% of 2121 children from the Isle of Wight were diagnosed "Hyperkinetic Syndrome." Schachar et al. (1981) using the Rutter scale on a subset of the same sample, identified 14.3% as hyperactive according to parent or teacher reports; another 2.2% were pervasively hyperactive. This discrepancy in the two prevalence rates

Received May :iO, !9H.5; accepted Sept. !H, !9H.5. Mr. Shapiro is a Dnctoral candidate in L'linical Psychology. Unioersitv uf Miami, Coral Gables, Florida. Dr. Garfinkel is Director uf the Dicisicm uf Child and Adolescent Psychiatry, University of Minnesota Medica! School, Minneapolis, MN .5.54.5.5. Correspondence and reprint requests may be made to Dr. Garfinkel. The authors with to thank John Hopwuod [or his technical assistance in data collection, 0002-71:1H/H6/2506-0H09 $02.00/0 (c· 1986 by the American Academy of Child Psychiatry. 809

810

S. K. SHAPIRO AND B. D. GARFINKEL

in the same population highlights the effect of using rating scale symptom endorsement alone, not in conjunction with diagnostic interviews. Schachar noted that those children who were not reassessed (28%) due to either noncompliance or missing data represented the more problematic children; thus, there was an underestimation of the prevalence of hyperactivity. Overestimation, however, may have resulted from the use of a rating scale from which the diagnosis was derived. Studies assessing large samples have helped to demonstrate the utility of a factor analytic description. Trites and Laprade (1983) identified 5.7% of a random sample of 9229 children with symptoms of hyperactivity. By controlling for the presence of conduct and emotional problems the prevalence rate dropped to 2.5%. Wray et al. (1980), using the 10-item abbreviated Conners (1969) Teacher Rating Scale (CTRS) identified 24.3% of :353 -Iamaican school children as hyperactive with 90% of these manifesting other problems. Many surveys (Glow, 1980; Goyette et al., 1978; Trites and Laprade, 1983; Werry et al., 1975; Wray et al., 1980) rely on one source of information to assess generalized behavioral problems. Rating scales are often easily influenced by demographic characteristics such as age, sex and socioeconomic status (SES) of the sample studied. Although rating scales provide useful clinical information, many of the factors derived from the CTRS are highly interrelated (Glow, 1980; Goyette et al., 1978; Trites et al., 1982; Werry et al., 1975). Parent interviews have also been used, although neither their validity nor reliability has been established for symptom or disorder recognition (Earls, 1980). Overall, many studies cannot be compared with each other because of inconsistencies in defining diagnostic criteria, instrumentation validity and sample heterogeneity. The purpose of the present study was to determine the prevalence of symptoms commonly associated with ADD in an elementary school population where every child could be assessed, thereby minimizing the bias from missing data (Cox et al., 1977). Instruments were chosen so as to collect information from as many sources and formats as possible. Assessment included a structured interview and therefore would reflect current nosology, increasing the opportunity to test the diagnostic criteria associated with ADD. It was hypothesized that based on a teacher rating scale, one group would show inattention and hyperactivity characteristic of ADD and could be distinguished from a second group that would demonstrate aggressive behaviors, consistent with Oppositional or Conduct Disorders. By using available measures, a multidimensional description of inattention/hyperactivity and aggression would be possible. The diagnostic

criteria for ADD would be examined to determine specificity and sensitivity for each criteria. Furthermore, the success of a diagnostic battery for ADD would be examined in differentiating symptomatic children from the remainder of the population of students.

Method SUBJECTS

Subjects consisted of all children (N = 315; 153 girls, 162 boys; x~ = 0.26, NS) attending grades 2 through 6 at a rural Minnesota public school in the fall of 1983. Ages ranged from 7 years to 12 years 10 months with a mean age of 9 years 10 months. All subjects were English speaking and more than 99% were Caucasian. INSTRUMENTS

Instruments were chosen on the basis of conceptual validity, ease of application for population screening, and ability to sample behavior in a variety of situations.

CTRS (Conners, 1969) Homeroom teachers completed the full 39-item rating scale.

Diagnostic Interview for Children and Adolescents (DICA) (Herjanic and Campbell, 1977) The ADD portion of this structured interview was administered by either one of two individuals. By means of concurrent interview, the percent of agreement for meeting the criteria for the diagnosis of ADD based on a random sample of 4 % of the children was 98%.

Attentional Battery This computerized assessment has been described elsewhere (Garfinkel and Klee, 1983; Klee and Garfinkel, 1983). Three separate tests were used: 1. Continuous Performance Task (CPT). This task is similar to the concept employed by Rosvold et al. (1956). The task consists of 13 letters flashing for 100 milliseconds in the center of a low resolution color video monitor. The order in which target (orange "S," blue "T") and nontarget letter sequences appeared is randomly generated. An error of omission is scored for each target missed, while a commission error is scored when a response is made to a nontarget stimulus. After ample practice to ensure comprehension, every child began at a rate of 1 second between letters and was shown 700 letters (seven 100-letter blocks). The interstimulus interval increased or decreased by 5% from the current frequency whenever an error or

811

ADD AND CONDUCT DISORDER

correct response was made. The ability to correctly identify the letters and colors was determined prior to testing. 2. Computerized Progressive Maze. This requires visual-motor integration skills as does the Porteus (191)9) Mazes. The task is to negotiate a movable square through a series of 16 progressively more difficult patterns with horizontal and vertical obstacles. Dependent variables for this task are the time taken to complete all 16 mazes and the number of errors incurred in the process. Feedback is given by a computer-generated tone when an obstacle is hit. :1. Sequential Urganization Test. This test is designed to assess the child's ability to organize in a non impulsive manner, a strategy for uncovering a hidden target. Beneath a 10 X 10 matrix of squares is a geometric figure hidden in an area of no more than 21)% of the grid. By use of a toggle and button, the child is asked to uncover the boxes, under which he or she thinks part of the figure has been placed. The time, and number of responses and sequences (at least two adjoining squares) taken to uncover the entire figure is recorded. Three figures of various complexity were used, the first being used for instruction and practice purposes.

SRA Achievement Series (Naslund, Thorpe, and Lefever) These are group administered tests assessing reading, arithmetic and language achievement and percentile scores based on a national normative sample. PROCEDURES

Teachers and school personnel were asked to provide demographic, family, academic, medical, and behavioral information about their home room children. Children were randomly assigned to one of two individuals who administered questionnaires and computerized tests during the regular school day. Within a 7week period every child participated for approximately 41) minutes to complete the screening procedures. Testers were blind to ratings on the teacher rating scale and were not aware of any child's academic achievement and/or behavioral characteristics. In order to identify index and comparison groups, the CTRS was used. This decision was based on research demonstrating its documented clinical usefulness, validity and reliability (Gittelman-Klein et al., 1976; Zentall and Barach, 1979). Based on empirical criteria, Loney and Milich (1982) identified two relatively independent dimensions using CTRS items. The five items comprising the Inattention-Overactivity subscale are: fidgety, hums and makes other noises, excitable/impulsive, inattentive/easily distracted, and short attention span. The five items on the Aggression

subseaIe include: quarrelsome, acts "smart," temper outbursts, defiant, and uncooperative. Criteria scores greater than 7 for Inattention/Overactivity and 4 for Aggression were set. In order to compare a different classification based on factor analysis, factors derived by Werry et al. (1975) were used. This comparison would provide the opportunity to compare clinically (Loney) with statistically (Werry et al.) derived definitions of these clinical problems. To identify the utility of the CPT for evaluating behavior problems, a poor CPT performance group was formed. This group included subjects who obtained a slow rate (X + 1 S.D.) in comparison to their peers. This poor CPT performance was based on the arithmetic average of the rates obtained from blocks 3 through 7. Results

Demographic Features Biographical and socioeconomic information describe a middle class, rural community. Of the children 78.7% came from intact homes; an additional 13% had only one biological parent living at home. For fathers, the modal social position (Hollingshead, 1957) was 5 with a mean of 3.8; mothers had a modal social position of 4 with a mean of 4.3. The unemployment rate was 1.3%, considerably lower than the state and national average. This community represents intact, working class, nonsuburban families. School-based assessments had identified frequencies for learning disability of 3.5%, educable mental retardation of 1.6% and behavior disorder (unspecified) of 1.3%. Another 7.1% were receiving some form of remedial education, leaving 86% of the total enrollment of grades 2 through 6 in the regular educational and/or behavioral programs for which remediation was not necessary.

Symptom Rating Measures Figure 1 presents an age-based scattergram of total scores obtained on the CTRS. If a score of 58.5 (mean ± 1.5 S.D.) is used to identify behavioral problems, 7 children were identified. If one standard deviation above the mean for each age group were used, this identifies 10.5% (N = 33) of the children (two standard deviations identifies 1.1% (N = 4)). CTRS scores for this population does not reflect a normal distribution. Figure 2 presents the total number of symptoms endorsed by each child during the diagnostic interview (DICA) for ADD. Symptom-free interviews were obtained for 26% of the children. However, 19% of the children endorsed 6 or more items out of 20, a level which, in conjunction with information concerning

812

S. K. SHAPIRO AND B. D. GARFINKEL 7

• Sc«t .:~ • Scan ' X• 1S0 • Scort ' 2S0

-lO' .

(N·3S)

r•

8 (N.SS)

Ul ... til

9

Q,)

(N-59)

>-

Tolal H - 315

.e

.

~

Q,)

10

Cl

(N-S1)


.~

11

no·

JI...... 1.

(N-73)

12

.-

I

IN-20)

0

10

20

••

30

40

50

60

70

80

90

Total eTRS Score

~7

10'1<;. 1. Total score on CTRS. (U)

80 70

.. c

60

Ui

40

.

30

E

20

41 "tJ :::l

'0 QI

lSi)

SO

(H)

131)

(25)

.c

:::l

Z

10 (2) 14) (21 (4)

12) 131

tl)

0

o

>J

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 20 Number of Endorsed Interview Items

10'1<;. ~. Endorsement of OleA interview questions by all stu-

dents. D criteria.

= students without

ADD criteria;.

= students with ADD

onset and duration, is used to diagnose ADD (Herjanic and Campbell, 1977). Twelve children were excluded because of mental retardation, neurological impairments, and epilepsy. A sample of :303 children resulted; 7 (2.3%) children (6 boys, 1 girl) had elevated ratings on the InattentiveOveractive factor and 11 (3.6%) children (9 boys, 2 girls) were rated highly on the aggressive factor. An additional 9 (3.0%) children (8 boys, 1 girl) met criteria for both clinical problems (Loney and Milich, 1982). Comparison of the 27 (8.9%) Inattentive-Overactive and/or Aggressive children (index group) with the remaining 276 children (all others) is shown in Table 1. Fewer index children came from intact families and had more fathers of a lower SES. They were more often classified as learning disabled or having a significant behavior problem which warranted remediation prior to this study. Table 2 presents results from analyses of variance (ANOYA), with age and sex serving as covariates. The

index children were delayed academically in comparison with the rest of the children on each of the three SRA subscales. Behavioral ratings from the CTRS and symptom endorsement from the DICA interview indicated a heterogeneous variance (Hartley's F-max test) requiring log transformation between the two comparison groups. The index children scored five times higher on the CTRS total score and three times higher on the DICA, both of which were statistically significant. With factors derived by Werry et al. (1975), index children showed a much higher score on factors such as Conduct-Lying, Inattentive-Hyperactive, TensionAnxiety, and Unsociable. The Pearson Correlation between the Loney and Milich factors and the Werry et al. factors is reported in Table 3. Interfactor correlations of Inattention and Conduct Problems show more independence with Loney and Milich's factors (r = 0.67, p < 0.001) than with Werry et al.'s factors (r = 0.79, p < 0.001). Statistically significant differences (analysis of covariance) between the two groups on performance measures are presented in Table 4. After log transformation for variance stabilization, the index group showed a slower rate on the CPT arising from a higher rate of errors of commission. This suggests a greater tendency by the index group to commit impulsive responses. The Sequential Organization Test showed the index group to uncover more squares and have more uncovering maneuvers in a less organized manner (total sequences). Consistent with this profile of impulsivity and cognitive disorganization, index children also had a tendency to uncover squares which were not part of the figure (non-figure square removal), either by choice or by impulsive tendencies. They were also more rapid (shorter opening time) in finding an initial portion of the figure. Tables 5 and 6 compare the index and remaining children on the basis of individual symptoms endorsed during the Child Interview (DICA). In comparison with their schoolmates, children with significant aggressive and/or inattentive-overactive problems describe themselves as restless, fidgety, impulsive, overactive, poor attenders, having trouble staying on task, and a discipline problem in school which interfered with their schoolwork. The sensitivity of the differentiating items ranged from 26 to 52% and the specificity from 84 to 97%. The three symptomatic groups were compared by analyses of covariance with log transformation (Table 7). No statistical differences were found on the SRA achievement scores, DICA interview and attentional battery subtests. Multiple Regression Analyses were performed using

813

ADD AND CONDUCT DISORDER TABLE 1

Social and Familial Characteristics Index

= 27)"

(N

Charuct erist ic

~

Family situation Both biological parents Single biological parent Other Hollingshead Occupational Index Semiskilled or unskilled labor Father Mother Remedial Educational Services Learning disabled Behavior disorders Supplemental tutoring

All Other Children (N = 276)

~-

z

x (df= 1)

p

N(%)

N(%)

12 (14) 7 (26) H (:J(»)

116 (82) :3:3 (12) 17 (6)

4.46 :1.,')3 16.78

0.0,'; NS 0.001

7 (:I;') H (40) 10 (:17) ;, (18) 4 (1,';) 1 (4)

:1;' (1;') 1J2 (29) 29 (11) 8 (:1) 0(0) 21 (8)

4.;'0 0.74 1:1.:10 13.:30

0.0,,) NS 0.001 0.001

"Index children identified by scores on Inattentive-Overactive Factor (>7) and/or Ag-gressive Factor (>4) (Loney and Milich (1982». TABLE 2 Academic and Behavioral Ratings"

-

--~--------

Index (N = 27)"

Behavior

~-------''.:..-_--------------

All other Children (N = 276)

----

X SRA Percentile Scores' Reading (";) Arithmetic (e;) Lunguage (';;,) Conners Teacher Rating Scale" Total Score (based on :19 items) Teachers' severity rating Werry et al. (197;'): Conduct/Lying (I and VI) Inattentive/Hyperactive (II) Tension/Anxiety (IV) Unsociable (I II) Shyness (V) ADD Interview Score (number of DICA items endorsed)"

(s.n.)

X

F

(I, 299)

p

(s.n.)

:1:l.4 (27.2) :1:1.0 (2;'.9) 2H.4 (27.1)

1J7.:1 (27.:3) IJIJ.O (:10.1) ;';'.7 (27.9)

42.7 (20.:3) 1.6 (0.9)

8.1 (7.7) 0.1 (0.4)

79.0 227.6

<0.001 <0.001

20.4 (11.9) 1:3..') (6.:1) :3.1 (2.6) 4.1 (4.1) 0.,'; (I.:I)

1.7 (2.7) 4.9 (6.0) 1.0 (1.4) 1.1 (1.6) 0.6 (1.0)

427.4 129.8 4:3.3 47.6 0.02

<0.001 <0.001 <0.001 <0.001 NS

7.2 (4.:1)

2.,'; (:3.0)

:12.7


14.0 10.:3 14.8

0.001 (WOO

0.001

" Ag-e and sex served as covariat es. "Index children identified by scores on Inattentive-Overactive factor (>7) and/or aggressive factor (>4) (Loney and Milich (1982». 'SRA test was not administered to 2nd grade: for this variable only, index N = 24, other N = 226 (df = 1,241J). "Variance was heterogeneous by Hartley's F-max test; ANOVA based on log- transformed data. TABLE :1 Conners Tmelll'r Ratiru; Scale Factor Scor» Comparison Loney and Milich (1982)

Werry et al. (197;')

InattentiveOveract ive

Conduct - Lying Inattent ive-Overact ive Unsociable Te nsion-Anxiet y Shyness

Ag~ressive

0.79' 0.9(j' 0.1J7' 0.:12' 0.0:1

0.96' 0.67' 0.1J2' 0.:1:3' -0.09

'p < 0.001, two-tailed Pearson r correlation test.

index children and their inattention-overactivity and aggression scores serving as the independent variable. Separately analyzing available demographic/academic

information, 23% of the variance within the inattentive-overactive score can be accounted for by special education. This was not a significant factor in predicting a child's aggression score (Table 8). Table 9 shows that for all three index groups the total variance accounted for by the Attention Deficit Disorder interview items is extremely high (95-96%). A different rank order of items is seen between the inattentive and aggressive scores. Items such as "talks at school when not allowed," "always on the go," and "problems concentrating on fun things" accounts for 47% of the inattentive score variance with 7 other items making up the remaining 48%. "Cutting and/or pushing in line," "problems concentrating on fun things," and "problems concentrating when noisy"

814

S. K. SHAPIRO AND B. D. GARFINKEL TARLE 4 Attcntional Hattery Performance"

All Other Children

(N=:m h

(N = 27li)

X (S.Il.)

X (S.Il.)

IH.H (fiB) 17.4 (17.:1) 97:Ul (fi79)

20.2 (fi.l)

1.,,0

NS

iz.s (]2.,~)

a.ss

7:>7.7 (:17,,)

7.f){j

0.0" 0.01

Hi:l.H (] 11 ) (202)

IH4.:l (1:19) 49:1." (177)

0.40 2.6H

NS (0.10)

so.s (H.7) :10.2 (lfi.9) IVi (9.4) 7.fi (H.7)

2H.9 (:>.4) ,,0.9 (42.") 10.:> (li.!i)

:l.H9

0.0"

Battery

Continuous Performance task Omission errors Commission errors' Average rate (rnsec}' Progressive Maze Test Errors Completion time (sec) Sequential Organization Test l J ncovering moves' Opening time (sees): Total sequences' Non-figure moves

- - - - - - ---~-----

Index

saz.s

F (1,299)

".9 (".4)

:l.H~l

O.O!i

!i.OO :1.!i7

o.os (O.Ofi)

- - - - -

" Age and

Sl'X

p

----

served as covariates.

/, Index children identified by scores on Inattentive-Overactive factor (>7) and/or Aggressive factor (>4) (Loney and Milich (19H2)). , Variance was heterogeneous by Hartley's F-max test; ANOVA based on log transformed dat a. TABLE

s

Frequency of Symptom Endorsement on Ann interview (Dl CA) -

~._---~----_._-_._.-

Differentiating Interview Items

Index" (N = 27)

All Other Children (N = 27fi)

P

(df= I)

N('.';,) --

Misses instructions by teacher Prohlems staying in seat at school Does not sit st ill Talks at school when not allowed Hushes through assignment s Numerous act ivit v changes Problems concent rat ing on schoolwork Starts games and leaves unfinished Does not listen Climbing on prohihited ohjects Hushes into things without

X'

-----------

- - - -

Sensitivity

Specificity

(I.';,)

(%)

Predictive Value ('i;')

Nr;;,) -------

------~-----

12 (14) 1:\ (·IH)

9 (:1) 22 (H)

1:1 (,IH) 14 (,,2)

:ll (II)

12 (44) II (41 ) 12 (44)

:>~J.OO

:Hi.fiH

0.001 0.001

44 4H

97 92

,,7 :17

:14.liO 27.44

0.001 0.001

4:,

92 H9

:17 :ll

2(i (9) 2H (Ill) :14 (12)

2:UlO 17 :lO

44 41 44

91

is.zo

0.001 0.001 0.001

HH

:12 2H 26

9 (:\:1)

2:\ (H)

14.fiO

0.001

:1:1

92

21'

9 (:1:1) 7 (26) H (:1:1)

2H (10) HJ (7) '29 (II)

IO.HO 10.:>·1 1O.!iO

0.01

:l:l 2fi :lO

90

o.oi o.m

H~J

24 '27 '22

(i (22) 10 (:m ~J (:1:1)

I:> (,,) 41 (]!i) 4:> (Hi)

9.7:1 fi.97 4.0:1

9!i H!i H4

29 '20 17

22 (H)

f)2

gO

~J:l

thinking Cutting and/or rushing in line Fidgets a lot Excessive running in house

IUJI

22

o.or

:17

0.0"

:n

----------

"Index children identilied by scores on Inattentive-Overactive factor (>7) and/or Aggressive factor (>4) (Loney and Milich (l9H2)). TABLE s Frequency of Symptom Endorsement on Ann interview (niCA)

Undifferent iat inl( Interview Items

Index" (N = 27)

All Other Children (N = '276)

----------

N(';;,)

N (U;,)

2 (7) ~J (:1:1) :1 (Ill II (41 ) 12 (44) 10 (:l7j :1 (II)

7 (2) :,7 (21) I" (!i) 4:1 (Ili) 9:1 (:14) HO (29) 2fi (9)

X

(df= I)

- - - - - -- - - - - - - -

Problems concentrating on fun things Needs to be reminded about chores Leaves dinner table before finished Always "on the 1(0 " Rest less sleeper Problems concentrating when noisy Unfinished schoolwork or homework

----.-

----- ---

-

I.~JO

1.79 1.:14 0.79 0.79 O.!i" 0.07 ---------

P

Sensitivity

Specificity

(I.';,)

(';;')

Predictive Value (%)

-------------

NS NS NS NS NS NS NS

7 :l:l II 41 44

:\7

97 79 9!i H4 66 71

:n

sz

22 14 17 20 II II 2H

"Index children identified by scores on Inattentive-Overactive factor (>7) and/or Agl(ressive factor (>4) (Loney and Milich (191''2)).

815

ADD AND CONDUCT DISORDER TABLE i J)iff"n'nt iatian of Index Group" InattentiveOveractive Hattery

(N= i) ----- - .---

-

Co n ne rs T eacher Hat ing Scale T ot al score (based on :1!J it ems} " Teach er s' scve r it v rating Loney a nd M ilich (I !J82) : In a t tent ive -Ove ra c t ive" Aggr es siw h W erry et a l. (19i !i ): Conduct -Lying (I and VI) Inattent ive -Hyperactive (II) T ensi on -Anxiety (IV) Unsociahle (I II)

- --- - - -- ----- -

-

X (S .D . )

:11.4 n .7) 1.1 (0.9 )

6:1.6 ( 18.0 )' 2.:1 (o .:W

22.0:1 6.4 0

0.00 1 0.01

1:1.71 :10.47

0.001 0.001 0.001 0.001 NS 0.001 NS

11.8 (2 .,, )d

9.2 (.'i.1) 1

li .i (4.4)1 i .2 (1.8)' :1.:1 (2.8) 1.8 u.s:

:32.:1 (10.2)1 19.8 (!i.4)' 3.6 (2.0)

0.4 (0 .8)

0.4 (0.8)

22. 60 47.81 0.60 9.!i9 0.66

6.i (4 .2)

8.2 (4.7)

O.i:3

16.2 (1.8)" 2.2 (:1.2) 2.9 (:1.4) 0.9 (2.2)

-

X (S. D. )

F (2, 22 )

4.!i (1.9 ) 6.i (1.6)"

n.s:

-

(N=9 )

9 .6 (1 .:1)" J.:l

6.i (4.6)

ADD Int erview Score (number of DICA it ems endorsed) -

(S. D.)

Both

(N = 11)

p

- --~- - - --------------------------

:\1.:1 (9.0) 1.6 (O.!i)

Shyn ess (V)

--

S

Aggr es sive

9.7 (4 '(J)"

8.0 (4 .•' i)'

NS

-

.. Age a nd se x served as covariat es, h Va r ia nce wa s het er ogeneous hy Hartley's F -max test ; A NOVA ba sed o n log transformed data . . " Bo t h " > " l na t te nt ive- Ove rucr ive" a nd " Aggress ive" hy S ch effe, P < 0.0:1. •, " Bot h" and " Inn t tent ive-O vera ct ive" > " Aggress ive" hy Scheffe, p < 0.0:1. . " Bot h" a nd " Aggress in'" > " Ina t te nt ive -Overactive" by Scheffe.n < 0.0:;. I " Bot h " > "Aggressi vl''' > " Ina t t ent ive-Overact ive" by Sch effe. p < O.U!i. " " Bo t h" > "Inut tent ive -Ov ernct ive " > " Aggress ive" by Sch effe, p < 0.0;).

TABLE 8 Amd"mic and l lvmngrttphir Ch nrucu -rics: Mult iple Reur cssinn All alysis (fill/ex Ch ld rcn (N = 2(;))" - --

-

Account ed Score Variance C ha rnrt eri st ir

l nnt n-nt iveOveract ive Aggr essive

( ' ~;,)

Inatt entiveOveractive

+ Aggressive

Sp ecial rem edial education Sex Agp Family si t ua t io n Fat hers ' occ u pa t ion

2:\ 4 2 2 2

1 4 2

T ot al accou nted va r ia nc e

:1:1

i

(i

" Jnd ex c hi ld re n identified by scores o n lnattent ive-Over active tart or (;;.7) and/ or Aggressiw factor (2:4 ) ( Lo ney and M ilich . 191'\ 2 >'

accounted for :~8 % of the aggressive score variance with 14 items accounting for the remaining 118% of the variance. Table 10 s hows that the average rate on the CPT accounted for equal portions of the variance (14-16 %) for the inattentive-overact ive and aggressive score. The level of inattention (CPT omissions) accounted for 7% of the variance on the inattentive scores. In contrast, errors obtained on the Progressive Maze Test accounted for 7% of the aggressive score variance. In forming the group of poor CPT performers (slow rate), the cutoff scores for the individual age groups

ranged from 1733 msec (between letters) for age 7 to 754 msec for age 12. Of this group, 29% were also cla ssified as having significant inattention-overactivity and/or aggression according to the criteria used by Loney and Milich (982) . Excluding children in grade 2, the CPT index group (N = 23) showed a higher frequency of receiving remedial educational services (39 %) compared to the other children (8%; X~ (1)-18.20, P < 0.001). Table 11 demonstrates that the poor CPT performers (covarying for age, sex and composite SRA score) were significantly worse on Werry et al.ls (1975) Conduct factor with trends toward signficance for the Hyperactive/Inattentive and Unsocialized factor. On fa ctors derived by Loney and Milich (1982) , group differences were significant only for Aggression. They were significantly worse on the overall teacher rating of severity but not on total rating scale score. Table 12 lists the items from the ADD interview (Ol CA) that are significantly different when comparing the poor CPT performers to the remaining stu dents. These characteristics are: "Does not listen," "Numerous activity changes," "Excessive running" and "Problems concentrating when noisy."

Discussion Using criteria established by Loney and Milich (I982) a prevalence rate of 2.3% (N = 7) was found for inattention-overactivity, Eleven or 3.6% showed significant problems with aggression, and 9 (3.0 %) or

816

S. K. SHAPIRO AND B. D. GARFINKEL

TABLE H Ann l ntcrtneu: (Iuestions: Multiple Regrcssum Anolvsu (Index Children (N = 26))"

TABU<: 10 Attcntional Hattery: Multiple Regression Analysis (index Children (N = 26))" Accounted Score Variance (%)

Accounted Score Variance (';;,) Questions

InattentiveOveractive Inattentive. Overactive Aggressive +

Battery

InattentiveInattentive- A ,Overactive Overactive ggressive + Aggressive

Aggressive Talks at school when not allowed Always "on the go " Problems concent rat ing on fun things Problems concent rat ing when noisy Does not listen Starts games and leaves unfinished Rushes through assignments Numerous activity changes Cutting and/or pushing in line Excessive running in house Restless sleeper Climbing on prohibited things Problems concentrating on schoolwork Unfinished schoolwork or homework Problems staying in seat at school Does not sit still Needs to be reminded about chores Fidgets a lot Rushes into things without thinking Total accounted variance

I()

:1

10

)(;

4 H

I:l

12

Continuous Performance Task Average rate Omissions Commissions Completion time Sequential Organization Test Opening moves Uncovering time Non-figure moves Uncovering moves Progressive Maze Test Errors Completion time

(j

III

7

14

H H

:l 4

Hi I

Ii Ii 4 4 I

2 4 2:l :l 4 7 :1

2 10

4 ;)

Total accounted variance

14 7

Hj

2

2

Ij

:l I

:l

:l6

:lS

7

:IR

a Index children identified hy scores on Inattent ive-Overacuve factor 1>7) and/or Aggressive factor (>4) (Loney and Milich, IHH2).

;)

4

9;'

:l

:l

;, .j

I :l

;)

2

Hli

99 -- --_.

__ .

----

"Index children identified hy scores on Inattentiw-Overactive factor (>7) and/or Aggressive factor (>4) (Loney and Milich, IHH2).

:33% of the index group manifested problems in both areas. In the present study, when compared to the remaining 276 children, the index group more frequently showed a broken family structure, lower socioeconomic class, more educational difficulties, greater cognitive disorganization, impulsivity, and more endorsed items on the ADD portion of the DICA child interview. These characteristics describe behaviorally problematic cbildren with respect to inattention, impulsivity and aggression. Using factors derived by Werry et al. (1975), children with both inattentive and aggressive problems had signficantly more problems with conduct, inattention and unsociability than the other two symptomatic groups. Analyses based on a group of poor CPT performers showed that the CPT was useful in identifying the academically delayed, aggressive/oppositional and restless child. Univariate analyses based on the Loney and Milich (1982) CTRS criteria could not differentiate the in-

attentive group from the aggressive group. Many items from the ADD interview showed comparable endorsement for each of the clinical groups. Concentration problems, impulsivity as well as excessive motoric behavior were associated equally with both. Impulsive behavior and cognitive disorganization as demonstrated by the attentional battery were significant factors associated with both groups. Although similar characteristics between an aggressive child and an inattentive child emerge from univariate analyses, lending little support for pathognomonic features, multivariate regression analyses demonstrate the relative importance of different individual symptoms for these clinical problems. The need for remedial education was useful in predicting only a child's level of inattention. The predominant items for the aggression score using the ADD interview questions were: "pushing or cutting in line," "problems concentrating on enjoyable things" and "problems concentrating when noisy." Inattention was characterized by: "talking when not allowed," "always on the go" and "problems concentrating on enjoyable things." Almost twice as many items contributed to the aggression score variance than to the inattentive-overactive score variance, although the total accounted variance was equal. The screening instruments, therefore, identify sensitive characteristics but indicate few specific criteria unique to either inattention or aggression. In attempting to explain why no dependent measure could differentiate between inattentive-overactive and

817

ADD AND CO N D UCT DI SORDER TA BLE 11

Beh avioral Ratinus: Continuous Performan ce T ask Index Group·

- - - --

Ra t ings -

-

- - - - _ .-

-- - -

--

-

--

C PT Index (N = 2:J)

All ot he r Chi ld re n (N = 2:11)

F (I, 244 )"

24 .9 (2;' .2) 1.0 ( 1.11)

10.2 (12.1) 0.2 (0.;')

2.44 11.1\6

NS 0.00 1

0 .0;' (0 .07) NS (0 . 10) NS

1.91

p - -- - X (s .n.) X (s.n.l - ---- - -- - - -- - - - - - - - - - - - -- - - - -- - - - - -

Conne rs Teac he r Ra ting Scale' : Tota l sc o re (based o n :19 items) Teac he rs ' seve r ity ra t ing Werry et al. (HI71i): Cond ucl / Ly ing ( I a nd VI) I na t tent ive / Hype ract ive (Ill T e ns io n -An xiet y ( IV) Unsociah le (Ill) S hyness (V) Lon ey a nd Milich (1982): ln att e n t ive-Overact ive Aggr l's s iv!'

9 .9 (l4 .:I) H.O (7 .H) 1.7 (2 .0) :1.0 (:1.1\) 1.0 ( 1.;' )

:1.0 :"1.2 1.2 U 0 .1i

(2 .0) (0 .9)

;' . 12 :1.26 0 . 18 2.71) U:I

4.;, (4.2) :1.1 (4.;')

1.8 (2.;' ) O.R ( 1.9 )

7.;':1

NS 0.01

;' . 1 (4.1)

2.8 (:1.:1 )

2.49

NS

AD D Int er view Score: (number of DIC A it e ms endorsed}'

(;'.1\)

(4 .11 (J.(;)

- - - --- - - - - - - - - --

" C P T index gro u p defined by C P T rate > X + 1 sta nda rd devia ti o n for eac h age gro u p (excl ud ing gr ade 2) . "Agl'. SI 'X a nd co m posit c S RA per ce nt ile se rved as rova rrat es. , Va ria nce was het ergen eou s by Ha rt lev's F -max lest ; A N OVA based o n log t ra ns formed dat a . TA HLE 12

Frequcncv of ....tymptnm _.. -Endorsement .__ ... Differe nt iut in g Intervi ew It em s

Does not list en Nu merous ac tivi ty c hanges Ex cessive runn ing in hou se P roble ms co nre nt ra t ing when no isy

CPT Index (N = 2:11

- _._.... _. .

.

(1/ 1

A IJIJ lnteroicu: ({)ICA) : Continuous Performance

All othe r C hi ld ren (1\ ' = 2:11)

N( ";·)

N

!I !) 10 12

14 ((j) 14 (H) 1:1 (li) \1 (;,)

(:m)

(:l!l) (.1:1)

(;,2)

( ~' ;,)

x"

id] = II

p

1:I.HO 11.4:1 H.21\ 4.0 1

0 .00 1 0 .00 1 0.001l 0 .0;'

T(J.~k

Ind ('x Group·

Se nsitivity

Specificity

(',';,)

( %)

Predi cti ve Va lue ( %)

:19 :19 4:1 1l:1

90 89 84 7\

28 2H 21 11l

- - - - - - - - - - --n

CPT Ind e x (;rou p defin ed by CPT Rate>

X+

1 sta nda rd dev ia t ion fo r eac h a ge group (e xcl ud in g gra de 2).

aggressive children, con sideration must be given to the que stion of whether or not a n independent ADD synd rome exists. Sandberg et al. (1978) noted that man y child ren diagnosed as hyperactive in the United Sta tes would be regarded in Great Britain as having Conduct Disorder. Furthermore , Sa ndberg argued that ther e were no pathogn omoni c sympto ms for the hyperk ineti c disorder. Beitchman et al. (1978), reviewing cha rts of pat ients who were given DSM-II diagnoses of undersocialized aggr essive disorder and hyperk ineti c disorder demonstrated impulsivit y, hostility and a nti social beh avior to he pr esen t in hoth diagnosti c groups . Stewart et al. (1980) showed a n association of pa ren tal psychopathology with Con duct Disorder but not with Hyp er acti vit y. August and Ste wart (1982) provided add it ional suppor t for t he diagnosti c distinction between "pure" hyperact ivity an d hyperactivity with conduct problems but could not ide nt ify discr iminating facto rs, Offord et al. (1979), however, determined t ha t hyperactive delinquents in comparison to non-

hyp eractive delinquents, had a lower birth weight, more delivery and postnatal complications, with earlier onset and more antisocial sympt oms. These two groups could not be differentiated with respect to IQ, SES, family history of alcoholism and the occurrence of disrupted families . Edelbrock et al. (1984) using the Teacher Child Behavior Checklist (1983 ) found the ADD child without hyperact ivity to be more socially withdrawn , less aggressive, and less self-destructive t ha n his counterpart with ADD and hyperactivity. Crit iquing the DSM-III ADD cla ssification, Loney (l 9 R~ ) showed that Conduct Disorder is considered a complicat ion of ADD. She suggested that the opp osi t ional child use s procrastination and dawdling as purposeful resi stance, whereas the ADD child, with his highly variable behavior, uses these behaviors unintentionally. In general, clin ical features which cha racterize behaviorally symptomatic children include low IQ, poor reading skills, and large famil y size but not SES (Rutter et al., 1976) , the quality of the parentchild relationship, the presence of mental illness in

818

S. K. SHAPIRO AND B. D. GARFINKEL

the parents (Earls, 1982); severe and persistent tension such as marital discord (Stott, 1973, 1978); child abuse, seizures and head injuries (Lewis and Shanok, 1979); and the level of family, social and academic achievement (Kolvin et aI., 1977). The present study provides additional support for some of these earlier results. A common problem arises when studying children from a nonreferred population. A low frequency of severely symptomatic children is found exhibiting the defining characteristics of a clinically derived sample. This low frequency precludes many multidimensional analyses which are useful in developing nosological models . Although some children manifest symptoms which reflect behavioral problems (Loney and Milich, 1982), many do not demonstrate these problems to be of a sufficient magnitude for psychiatric referral or intervention. The presence of individual symptom clusters does not indicate the presence of either a behavioral disorder or psychiatric syndrome. It may be that having multiple symptom clusters determines clinical referral. The methodology used in this study represents in many ways significant improvement over previous epidemiological surveys of ADD. First, an entire elementary school population of nonreferred children were studied. Second, a variety of assessment techniques, all with proved validity and reliability, created a multimodality assessment. The DICA interview based on current DSM-III criteria for ADD was included. Previous studies based their assessment on less structured formats; consequently their validity was not established. Third, all materials were collected blindly, so that neither academic record nor behavioral rating would influence interview style or instructional set for the computerized assessment battery. Fourth, in analyzing tbe data, two factor structures (Loney and Milich, 1982; Werry et aI., 1975) were used for comparison. Previous research has often emphasized statistical derivation and has not compared this with a clinically based factor derivation, such as Loney's. Also, univariate as well as multivariate analyses were used, demonstrating the need for multidimensional descriptions of ADD. There were a number of limitations with the present methodology used. Because of the population characteristics, this group cannot be considered representative of a "typical urban community." The decision to use this socially and culturally uniform population was to assess prevalence rates of behavior problems in a rural setting, relatively free from significant urban stressors. In this manner, prevalence rates hopefully reflect more accurately disorder base rates rather than social/cultural factors. Epidemiological investigations

require a fairly brief screening protocol and therefore, concurrent parent ratings obtained by either interview or rating scale might have identified a more pervasively disturbed group of children. This would have resulted in a high rate of missing data and bias. Obtaining a complete family psychiatric history would have provided information concerning the genetic background to specific behavior problems. Classroom based structured observation would have been useful for information concerning behavior in a more natural setting. In addition, the full diagnostic interview for children was not used because of time constraints. Results from this may have shown that although a child met criteria for ADD, this would not have been his/her primary diagnosis. Subsequent services provided to the identified index children have included an extensive assessment including parent ratings and family history. Although complete findings will be presented at a later date, preliminary findings (obtained through a complete diagnostic interview with the child and parent D1CAP) and valid and reliable parent-rating scales show that similar symptoms were identified resulting in diagnoses of either ADD or Conduct Disorder in all cases. In summary, it was possible to identify and describe behaviorally disturbed children from an elementary school population using a teacher rating scale, clinical interview and performance measures. Without associated agressive behavior, 2.3% of the children showed significant symptoms of the ADD syndrome. The prevalence rate of aggressive behavior was 3.6%; 3.0% showed both problems. Although the population could be divided into these three groups by the CTRS, no other measure such as the child interview, attentional battery or school performance could validate this diagnostic distinction. These results suggest that characteristics commonly associated with ADD are not specific to this syndrome and should not be viewed as exclusive of Conduct Disorder. However, further study is necessary with a larger symptomatic group from a nonreferred population in order to assess whether the lack of difference is a statistical artifact. The discrim inating power of the ADD interview, particularly in a multivariate format with its more sensitive and specific items, demonstrates its usefulness in identifying behaviorally problematic children. It fails, however, to identify only the ADD child. There is no evidence that the inattentive-overactive child suffers from neurological impairment. Based on the attentional battery, primary problems concern impulsivity and cognitive disorganization and not from eye-hand coordination deficits. Further epidemiological research must attempt to identify symptoms specific to ADD, based

ADD AND CONDUCT DISORDER

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819

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