Embed Size (px)
Citation preview
This article was downloaded by: [b-on: Biblioteca do conhecimento online UC]On: 03 November 2013, At: 14:51Publisher: RoutledgeInforma Ltd Registered in England and Wales Registered Number: 1072954 Registeredoffice: Mortimer House, 37-41 Mortimer Street, London W1T 3JH, UK
The Clinical NeuropsychologistPublication details, including instructions for authors andsubscription information:http://www.tandfonline.com/loi/ntcn20
Do executive function deficitsdifferentiate between children withAttention Deficit Hyperactivity Disorder(ADHD) and ADHD comorbid withOppositional Defiant Disorder? A cross-cultural study using performance-basedtests and the Behavior Rating Inventoryof Executive FunctionYing Qian a , Lan Shuai a , Qingjiu Cao a , Raymond C. K. Chan b c &Yufeng Wang aa Institute of Mental Health, Peking University , Beijingb Neuropsychology and Applied Cognitive Neuroscience Laboratoryc Key Laboratory of Mental Health, Institute of Psychology, ChineseAcademy of Sciences , Beijing, ChinaPublished online: 25 Jun 2010.
To cite this article: Ying Qian , Lan Shuai , Qingjiu Cao , Raymond C. K. Chan & Yufeng Wang (2010)Do executive function deficits differentiate between children with Attention Deficit HyperactivityDisorder (ADHD) and ADHD comorbid with Oppositional Defiant Disorder? A cross-cultural study usingperformance-based tests and the Behavior Rating Inventory of Executive Function, The ClinicalNeuropsychologist, 24:5, 793-810, DOI: 10.1080/13854041003749342
To link to this article: http://dx.doi.org/10.1080/13854041003749342
PLEASE SCROLL DOWN FOR ARTICLE
Taylor & Francis makes every effort to ensure the accuracy of all the information (the“Content”) contained in the publications on our platform. However, Taylor & Francis,our agents, and our licensors make no representations or warranties whatsoever as tothe accuracy, completeness, or suitability for any purpose of the Content. Any opinionsand views expressed in this publication are the opinions and views of the authors,and are not the views of or endorsed by Taylor & Francis. The accuracy of the Contentshould not be relied upon and should be independently verified with primary sourcesof information. Taylor and Francis shall not be liable for any losses, actions, claims,
proceedings, demands, costs, expenses, damages, and other liabilities whatsoever orhowsoever caused arising directly or indirectly in connection with, in relation to or arisingout of the use of the Content.
This article may be used for research, teaching, and private study purposes. Anysubstantial or systematic reproduction, redistribution, reselling, loan, sub-licensing,systematic supply, or distribution in any form to anyone is expressly forbidden. Terms &Conditions of access and use can be found at http://www.tandfonline.com/page/terms-and-conditions
Dow
nloa
ded
by [
b-on
: Bib
liote
ca d
o co
nhec
imen
to o
nlin
e U
C]
at 1
4:51
03
Nov
embe
r 20
13
The Clinical Neuropsychologist, 24: 793–810, 2010
http://www.psypress.com/tcn
ISSN: 1385-4046 print/1744-4144 online
DOI: 10.1080/13854041003749342
DO EXECUTIVE FUNCTION DEFICITS DIFFERENTIATEBETWEEN CHILDREN WITH ATTENTION DEFICITHYPERACTIVITY DISORDER (ADHD) AND ADHDCOMORBID WITH OPPOSITIONAL DEFIANT DISORDER?A CROSS-CULTURAL STUDY USING PERFORMANCE-BASED TESTS AND THE BEHAVIOR RATINGINVENTORY OF EXECUTIVE FUNCTION
Ying Qian1, Lan Shuai
1, Qingjiu Cao
1, Raymond C. K. Chan
2,3,
and Yufeng Wang1
1Institute of Mental Health, Peking University, Beijing, 2Neuropsychology
and Applied Cognitive Neuroscience Laboratory, and 3Key Laboratory ofMental Health, Institute of Psychology, Chinese Academy of Sciences,Beijing, China
This study examined the differential executive dysfunction of children with attention deficit
hyperactivity disorder (ADHD) and those with ADHD and oppositional defiant disorder
(ODD) in Han Chinese. A total of 258 children (89 ADHD, 53 ADHDþODD, 116
controls) completed performance-based executive function tests and had their everyday life
executive skills rated by their parents using the Behavior Rating Inventory of Executive
Function (BRIEF). Both the ADHD and ADHDþODD groups performed worse than the
controls in the Stroop and Trail-making tests and the BRIEF. The ADHDþODD group
were rated worse than the ADHD group on the BRIEF, but the two groups showed no
significant difference in the performance-based tests. These findings suggest Han Chinese
children with ADHD display executive dysfunction in performance-based tests and
everyday life scenarios, in a similar way to findings in Western counterparts. However,
children with ADHDþODD showed more severe executive dysfunction in everyday life
scenarios than those with ADHD only.
Keywords: Attention Deficit Hyperactivity Disorder; Oppositional Defiant Disorder; Executive function;
Inventory.
INTRODUCTION
Attention deficit hyperactivity disorder (ADHD) is the most commonbehavioral disorder in childhood (Castellanos & Tannock, 2002). Differingexecutive function abilities (neurocognitive processes that maintain an appropriateproblem-solving set to attain a future goal; Welsh & Pennington, 1988) result insignificant variance in predicting the adaptive behavior, communication, and socialskills of children with ADHD (Clark, Prior, & Kinsella, 2002). However, out of 165
The Clinical Neuropsychologist, 24: 793–810, 2010
http://www.psypress.com/tcn
ISSN: 1385-4046 print/1744-4144 online
DOI: 10.1080/13854041003749342
DO EXECUTIVE FUNCTION DEFICITS DIFFERENTIATEBETWEEN CHILDREN WITH ATTENTION DEFICITHYPERACTIVITY DISORDER (ADHD) AND ADHDCOMORBID WITH OPPOSITIONAL DEFIANT DISORDER?A CROSS-CULTURAL STUDY USING PERFORMANCE-BASED TESTS AND THE BEHAVIOR RATINGINVENTORY OF EXECUTIVE FUNCTION
Ying Qian1, Lan Shuai
1, Qingjiu Cao
1, Raymond C. K. Chan
2,3,
and Yufeng Wang1
1Institute of Mental Health, Peking University, Beijing, 2Neuropsychology
and Applied Cognitive Neuroscience Laboratory, and 3Key Laboratory ofMental Health, Institute of Psychology, Chinese Academy of Sciences,Beijing, China
This study examined the differential executive dysfunction of children with attention deficit
hyperactivity disorder (ADHD) and those with ADHD and oppositional defiant disorder
(ODD) in Han Chinese. A total of 258 children (89 ADHD, 53 ADHDþODD, 116
controls) completed performance-based executive function tests and had their everyday life
executive skills rated by their parents using the Behavior Rating Inventory of Executive
Function (BRIEF). Both the ADHD and ADHDþODD groups performed worse than the
controls in the Stroop and Trail-making tests and the BRIEF. The ADHDþODD group
were rated worse than the ADHD group on the BRIEF, but the two groups showed no
significant difference in the performance-based tests. These findings suggest Han Chinese
children with ADHD display executive dysfunction in performance-based tests and
everyday life scenarios, in a similar way to findings in Western counterparts. However,
children with ADHDþODD showed more severe executive dysfunction in everyday life
scenarios than those with ADHD only.
Keywords: Attention Deficit Hyperactivity Disorder; Oppositional Defiant Disorder; Executive function;
Inventory.
INTRODUCTION
Attention deficit hyperactivity disorder (ADHD) is the most commonbehavioral disorder in childhood (Castellanos & Tannock, 2002). Differingexecutive function abilities (neurocognitive processes that maintain an appropriateproblem-solving set to attain a future goal; Welsh & Pennington, 1988) result insignificant variance in predicting the adaptive behavior, communication, and socialskills of children with ADHD (Clark, Prior, & Kinsella, 2002). However, out of 165
Address correspondence to: Yufeng Wang, Institute of Mental Health, Peking University, Beijing
100191, People’s Republic of China. E-mail: [email protected]
Accepted for publication: February 26, 2010.
� 2010 Psychology Press, an imprint of the Taylor & Francis group, an Informa business
Dow
nloa
ded
by [
b-on
: Bib
liote
ca d
o co
nhec
imen
to o
nlin
e U
C]
at 1
4:51
03
Nov
embe
r 20
13
published research papers, 109 (65%) have found that children with ADHD showmore significant executive dysfunction than those without ADHD (Willcutt, Doyle,Nigg, Faraone, & Pennington, 2005). Such executive dysfunction means thatchildren with ADHD are at high risk of grade retention and decreased academicachievement (Biederman et al., 2004). It is thus important to investigate executivedysfunction in children with ADHD.
Although ADHD occurs as a single disorder in a minority of diagnosedindividuals, in 80% of cases it is comorbid with other disorders (Barkley, DuPaul, &McMurray, 1990). The most frequent co-occurring psychiatric disorders includeoppositional defiant disorder (ODD, 54–67%) (Barkley et al., 1990) and conductdisorder (CD, 20–56% of children and adolescents) (Biederman, Newcorn, &Sprich, 1991). Individuals with ADHD and ODD or CD display higher levels ofdelinquency, overt aggression, and ADHD symptom severity than those withADHD only (Connor & Doerfler, 2007). Individuals with ODD and CD have alsobeen shown to display executive dysfunction (Aronowitz et al., 1994; Oosterlaan,Logan, & Sergeant, 1998), although the evidence is not as strong as for ADHD.There is thus some doubt about how and to what extent the co-occurrence of ODDor CD (ADHDþODD/CD) influences executive dysfunction among individualswith ADHD.
Many studies have investigated the differences in executive function betweenindividuals with ADHD and those with ADHDþODD/CD, but the results aremixed. The most frequently used instruments in these studies are performance-basedtests. Most studies using these instruments have found that children withADHDþODD/CD are similar to children with pure ADHD but worse thannormal controls on some but not all aspects of executive function (Nigg, Hinshaw,Carte, & Treuting, 1998; Oosterlaan et al., 1998). However, other findings indicatethat the executive function of children with ADHDþODD/CD is significantlybetter than that of children with pure ADHD (Schachar, Mota, Logan, Tannock, &Klim, 2000; Schachar & Logan, 1990) and comparable to that of normal controls intasks of working memory, inhibition, and planning (Schachar & Logan, 1990;Schachar et al., 2000; Stephanie, van Goozen, & Cohen-Kettenis, 2004). In a studythat utilized the same sample as this study, the executive function of children withADHDþODD/CD was found to be worse than that of normal controls butsignificantly better than that of children with pure ADHD in measures of inhibition(Shuai & Wang, 2007), yet other findings have indicated that the executive functionof children with ADHDþODD/CD is worse than that of both normal controls andchildren with ADHD in measures of inhibition (Van, Marzocchi, & De, 2005).
A handful of studies in this field have used ecologically valid measurements,such as the Six Elements Test (Burgess et al., 1996) and the Hayling SentenceCompletion Test (Burgess & Shallice, 1996; Clark, Prior, & Kinsella, 2000) toexamine executive dysfunction in children with ADHD. These studies have foundthat adolescents with ADHD and those with ADHDþODD/CD are significantlymore impaired in their ability to generate strategies and monitor their ongoingbehavior than age-matched individuals with ODD/CD only.
Several factors may account for these different findings, of which the use ofdifferent instruments to measure executive function is particularly important. Thiswill be discussed in the next paragraph. Other potential confounding factors include
794 YING QIAN ET AL.
Dow
nloa
ded
by [
b-on
: Bib
liote
ca d
o co
nhec
imen
to o
nlin
e U
C]
at 1
4:51
03
Nov
embe
r 20
13
the treatment of individuals with ODD and CD as one group; ignoring the influenceof symptom severity, ADHD-subtype, IQ, gender, and age; and neglectingthe influence of other co-occurring conditions such as learning disorders(Seidman, 2006). It is thus important to control for these factors in a sample.
In terms of the influence of instruments, conventional performance-based testsare thought to reflect executive performance of the impairment level in highlystructured laboratory situations, but are not sufficient by themselves to capturedeficits in real-world behavior at the functional level (Chan, Shum, Toulopoulou, &Chen, 2008a). The inclusion of both the performance-based and ecologically validmeasures may capture the executive dysfunction of an individual in real life(Chan et al., 2008a; Gioia & Isquith, 2004). Most previous studies on ADHD wereprimarily limited to either the conventional performance-based tests or theecologically valid measures. However, recent studies suggest the superiority ofusing both performance-based tests and ecologically valid measures over usingeither one of them alone to assess executive dysfunction in clinical samples (Riccio,Homack, Jarratt, & Wolfe, 2006; Toplak, Bucciarelli, Jain, & Tannock, 2009).For example, in studies using performance-based tests alone, hyperactive childrentend be calm and attentive and show no executive deficit, since the tasks in thesestudies are usually simple, short term, and well directed (Draeger, Prior, & Sanson,1986; Mahone & Hoffman, 2007). In studies using ecologically valid measuresalone, parents show bias and may not give a true picture of their children (Abikoff,Courtney, Pelham, & Koplewicz, 1993; Christensen, Margolin, & Sullaway, 1992;Shallice & Burgess, 1991). Riccio et al. (2006) and Toplak et al. (2009) used two suchmeasures of executive function in patients with ADHD, and found that theecologically valid instruments of executive function provided information about thelevel of severity of the patient’s clinical and functional outcomes that conventionalperformance-based neuropsychological tests were unable to assess. This study thusemployed both performance-based and ecologically valid measures to detect thedifferential executive function performance between children with ADHD and thosewith co-occurring ADHDþODD.
The Behavior Rating Inventory of Executive Function (BRIEF) is one of thevery few tests specifically designed to assess everyday executive function in children(Gioia, Isquith, Guy, & Kenworthy, 2000). Children with ADHD have beenreported to have significantly higher scores for virtually all of the scales of theBRIEF compared to normal controls (Gioia et al., 2000). Moreover, only the parentand teacher rating on the BRIEF emerged as a predictor of ADHD status whenboth performance (stop task) and parent and teacher rating were entered aspredictors (Toplak et al., 2009). The current study adopted the Mandarin version ofthe parent form (Qian & Wang, 2007).
The four most commonly used tests (details in measures section) were includedto capture the executive dysfunction in highly structured laboratory situations inthis study, as findings have indicated that children with ADHD also exhibit weakperformance in tasks of inhibition and working memory (Seidman, 2006;Willcutt et al., 2005; Wodka et al., 2008) as well as tests of shifting and planning(Seidman, 2006; Wodka et al., 2008).
Treating CD and ODD as separate disorders eliminates another confoundingfactor. As ODD is considered to be a milder and earlier variant of CD (APA, 1994),
EXECUTIVE FUNCTION DEFICITS AND ADHD 795
Dow
nloa
ded
by [
b-on
: Bib
liote
ca d
o co
nhec
imen
to o
nlin
e U
C]
at 1
4:51
03
Nov
embe
r 20
13
the findings for children with ADHDþODD and those with ADHDþCD may bedifferent (Biederman et al., 1991; Connor & Doerfler, 2007). A genetic study showedthat there was a stronger correlation with executive function and co-occurringADHD and ODD than with co-occurring ADHD and CD (Coolidge, Thede, &Young, 2000). Thus, only including children with comorbid ODD may clarify therelationships among ADHD, ODD, and CD.
Given the above findings, the main purpose of the current study was to clarifythe confusing results of the latter studies on the differential executive functionbetween children with ADHD and those with ADHDþODD by using both theBRIEF and performance-based measures in the same sample and controlling forother confounding factors. Moreover, considering the influence of culture, it alsoaimed to provide the first data on executive function of children with ADHD usingboth the BRIEF and performance-based measures in the Han Chinese sample.
To achieve the above purposes, two hypotheses were explored in this study.First, a review of the literature suggests that Western children with ADHD mayexhibit deficits in particular aspects of executive function in both the ecologicallyvalid and performance-based measures regardless of the presence of ODD. Further,children with ODD only may exhibit subtle or no impairment in executive functioncompared with controls. It was thus hypothesized that Han Chinese children withADHD would be rated as more impaired than normal controls on executivefunction of performance-based tests as well as everyday life scenarios regardless oftheir ODD status. Second, children with both ADHD and ODD have been shownto display higher levels of symptom severity than those with pure ADHD. This leadsto the postulation that individuals with ADHDþODD will exhibit poorerexecutive function than those with ADHD only. However, the findings on thedifferential executive function of children with ADHD and those withADHDþODD are mixed on performance-based measures. Studies have alsofound that the BRIEF may provide meaningful information about an individual’severyday executive function to supplement the data provided by performance-basedassessments (Toplak et al., 2009), it was hypothesized that children withADHDþODD would display greater impairment in everyday executive function(as rated by the BRIEF) than children with ADHD only.
METHOD
Participants
The participants were screened for the most common child and adolescentpsychiatric and psychological disorders by using the Clinical DiagnosticInterviewing Scale (CDIS) for DSM-IV (Barkley, 1998). All of the participatingchildren met the following criteria: (a) aged between 7 years 0 months and 13 years 6months; (b) a full-scale IQ estimate of 80 or higher based on the Chinese-WechslerIntelligence Scale for Children (C-WISC) (Gong & Cai, 1993); (c) no evidence ofvisual or hearing impairment, speech/language disorder, or history of otherneurological or psychiatric disorders; (d) no history of treatment for ADHD; and(e) Chinese speaking and Han Chinese.
796 YING QIAN ET AL.
Dow
nloa
ded
by [
b-on
: Bib
liote
ca d
o co
nhec
imen
to o
nlin
e U
C]
at 1
4:51
03
Nov
embe
r 20
13
Diagnostic groups. The DSM-IV criteria (APA, 1994) were used todiagnose ODD and the three subtypes of ADHD, ADHD inattentive type(ADHD-I), ADHD hyperactive-impulsive type (ADHD-HI), and ADHD combinedtype (ADHD-C). Those who meet the criteria of both ADHD and ODD will bediagnosed as ADHDþODD. As there were not enough children with ADHD-HI(n¼ 5) to be included, only children with ADHD-I and those with ADHD-C wererecruited. Both groups were free of other comorbidities, including tics, phobias, andconduct disorders, learning disorders, and anxiety and mood disorders. Childrenwith ADHD (n¼ 89; ADHD-I n¼ 56; ADHD-C n¼ 33) and those withADHDþODD (n¼ 53; ADHD-IþODD n¼ 22; ADHD-CþODD n¼ 31) wererecruited out of 360 suspected outpatients from the Institute of Mental Health ofPeking University. Among those who were screened out, 9 children’s parents hadnot finished BRIEF (missing items42), 40 were not diagnosed as ADHD, and 169were diagnosed as ADHD co-occurring with other disorders.
Control group. A total of 116 healthy children were recruited out of 130children from two regular elementary schools as normal controls. Among those whowere screened out, 1 child’s parents had not finished BRIEF (missing items42), and13 were not diagnosed as normal.
Demographic information and the symptom severity of the participants areprovided in Tables 1 and 2. There were no significant group differences in the age orgender distribution of the participants. The children in the control group had asignificantly higher IQ score than the diagnostic group, F(2, 255)¼ 5.15, p¼ .006.According to the total score of the ADHD Rating Scale–IV (ADHD RS-IV), thetwo diagnostic groups had a significantly higher score than the control group,F(2, 255)¼ 165.72, p5 .001, whereas the ADHD group had a similar score to theADHDþODD group (mean difference¼ 1.667, p4.05).
Measures for screening and assessment of symptom severity
Clinical Diagnostic Interview Scale. The CDIS (Barkley, 1998) is astructured interview instrument based on the DSM-IV that assesses behavioraland emotional disorders during childhood, including ADHD, ODD, CD, tics, and
Table 1 Clinical characteristics of the ADHD, ADHDþODD, and control groups
ADHD ADHDþODD Control
n¼ 89 n¼ 53 n¼ 116
Mean SD Mean SD Mean SD F/�2 (2, 255)
Partial eta
squared
Age 9.07 1.92 9.25 1.79 9.19 1.62 0.20 0.002
IQ 108.24 13.66 107.04 13.44 112.81 11.52 5.15** 0.039
Gender (M:F) 76:13 42:11 97:19 0.92 0.004
Subtype of ADHD
(ADHD-I:ADHD-C)
56:33 22:31
ODD¼Oppositional-defiant disorder; ADHD¼Attention deficit hyperactivity disorder;
ADHD-I¼Attention deficit hyperactivity disorder inattentive type; ADHD-C¼Attention deficit
hyperactivity disorder combined type; M¼male; F¼ female; *¼ p5 .05; **¼ p5 .01.
EXECUTIVE FUNCTION DEFICITS AND ADHD 797
Dow
nloa
ded
by [
b-on
: Bib
liote
ca d
o co
nhec
imen
to o
nlin
e U
C]
at 1
4:51
03
Nov
embe
r 20
13
Table
2Raw
totalscore
fortheADHD
RatingScale
–IV
oftheADHD,ADHDþODD,andcontrolgroups
ADHD
ADHDþODD
Control
n¼89
n¼53
n¼116
Mean
SD
Mean
SD
Mean
SD
F(2,255)
Partialeta
squared
pADHD
vsControl
pADHDþODD
vsControl
PADHDþODD
vsADHD
Totalscore
forADHD
RS–IV
50.148
8.489
51.915
7.377
23.824
5.905
165.722**
0.725
5.001
5.001
0.107
Totalscore
forinattentivesubscale
27.815
4.263
27.872
3.938
12.382
2.907
210.111**
0.676
5.001
5.001
0.940
Totalscore
forhyperactive
andim
pulsivesubscale
22.333
6.033
24.043
5.200
11.407
3.116
64.534**
0.448
5.001
5.001
0.237
ADHD
RS-IV¼ADHD
RatingScale–IV
;ODD¼Oppositional-defiantdisorder;ADHD¼Attentiondeficithyperactivitydisorder;ADHD-I¼Attentiondeficit
hyperactivitydisorder
inattentivetype;
ADHD-C¼Attentiondeficithyperactivitydisorder
combined
type;
*¼p5
.05;**¼p5
.01.
798 YING QIAN ET AL.
Dow
nloa
ded
by [
b-on
: Bib
liote
ca d
o co
nhec
imen
to o
nlin
e U
C]
at 1
4:51
03
Nov
embe
r 20
13
emotional, affective, and learning disorders. The CDIS was introduced to mainlandChina in 2000. We had it translated and back-translated for clinical use. We kept theitems the same as the original one. The mandarin version of CDIS (Yang, Wang,Qian, & Gu, 2001) showed a good sensitivity (97.2%) and specificity (100%), with atest–retest reliability of 0.89. The inter-rater reliability kappa coefficient was 0.74( p5 .01). In the ADHD subscale, the CDIS distinguishes three types: ADHDinattentive type (ADHD-I), ADHD hyperactive-impulsive type (ADHD-HI), andADHD combined type (ADHD-C).
ADHD Rating Scale-IV (ADHD RS-IV). The instrument used to measuresymptom severity was the ADHD Rating Scale-IV (ADHD RS-IV), an 18-itemscale with 1 item for each of the 18 symptoms contained in the DSM-IV diagnosis ofADHD (Dupaul, Power, Anastopoulos, & Reid, 1998). Each item on the scale isscored from 1 to 4 (from never or rarely to very often). The rating scale assessedsymptom severity during the previous week, and was administered and scored byqualified and trained psychiatrists at the investigative site at first visit, based on aninterview with the parents. The total score was computed as the sum of the scoresfor each of the 18 items. In addition to the total score, scores were computed for theinattention and hyperactivity/impulsivity subscales.
Measures for assessment of executive function
Ecologically valid measure of executive function: The Behavior RatingInventory of Executive Function (BRIEF) parent form. The Behavior RatingInventory of Executive Function (BRIEF) parent form for children aged 5–18 yearsconsists of 86 items based on theoretically and empirically based definitions of theexecutive function construct (Gioia et al., 2000). Parents rate items related to theirchildren’s everyday behavior on a 3-point Likert scale (1¼ never, 2¼ sometimes,3¼ often). The instrument includes eight subscales: Initiate, Working Memory,Plan/Organize, Organization of Materials, Monitor, Inhibit, Shift, and EmotionalControl. A higher score indicates more problems in that area.
The Mandarin version of the BRIEF parent form was introduced into Chinaby our group in 2006. Initially we had the BRIEF translated by two native Chinesespeakers, and modified some items to fit Chinese mores or idioms. We then had theMandarin version of the BRIEF back-translated by a fully bilingual Chinesespeaker living in Canada. We then modified the Mandarin version of the BRIEFaccording to the suggestions of the original author. Finally we obtained writtenauthorization to examine the psychometric validation of the Mandarin version ofthe BRIEF parent form.
After about 1 year’s study, we established that the Mandarin version of theBRIEF parent form had good psychometric properties and clinical discrimination,with a test–retest reliability of 0.68–0.89 and a Cronbach’s coefficient of 0.74–0.96.The subscales of the Mandarin version of the BRIEF were moderately correlatedwith some of the subscales of other criteria scales (ADHD RS-IV and so on)(r¼ .41–.64), and indexes of performance-based tests of executive function(r¼ .32–.41). For example, the inhibition subscale of the BRIEF correlatedwith the Stroop word–color interference time test (r¼ .38), and the workingmemory subscale correlated with the time for trial B of the Trail-Making Test, thenumbers of backwards digit test, and the Stroop word–color interference time
EXECUTIVE FUNCTION DEFICITS AND ADHD 799
Dow
nloa
ded
by [
b-on
: Bib
liote
ca d
o co
nhec
imen
to o
nlin
e U
C]
at 1
4:51
03
Nov
embe
r 20
13
test (r¼ .30, �.39, .41, respectively). Confirmatory factor analysis showed theeight-subscale model of BRIEF was reasonable (Comparative Fit Index40.90,Root Mean Square Error of Approximation5 0.08). Diagnostic groups (ADHD,schizophrenia, and autism) had significantly higher scores than controls for almostall of the subscales of the Mandarin version of the BRIEF (Qian & Wang, 2007).
Performance-based tests of executive functions. The tests for this partof the study were selected from the battery used by our group for Chinese samples(Shuai & Wang, 2007), and they are the Chinese versions of the executive tasks mostoften used to test ADHD participants. The inter-rater reliability kappa coefficientsof the tests range from 0.70–0.75 ( p5 .01). The Chinese versions of the StroopColor–Word Test, Trail-Making Test, and Tower of Hanoi have been found todiscriminate well between ADHD and control groups (Shuai & Wang, 2007).
The following paragraphs are brief introduction of the tasks.
Inhibition: Stroop Color–Word Test (Stroop, 1935). The Chinese versionconsists of four parts, and uses three cards. Participants are required to name 30stimuli in a 3� 10 matrix as quickly and correctly as possible. They are asked toname (i) the words on the first card, (ii) the colors on the second card, (iii) the wordson the third card, and (iv) the colors on the third card as the four parts of the test. Inthis study the time taken to complete Part 4 minus that taken to complete Part 2 wasused as the index of inhibition.
Shifting: Trail-Making Test (Reitan, 1979). In Part A, participants areinstructed to connect, as rapidly as possible, 25 numbered circles (from 1 to 25)randomly distributed over an 8� 11 sheet of paper. In Part B, participants arerequired to connect 25 circles that contain numbers (from 1 to 13) or letters (fromletter A to letter L), and sequentially alternate between numbers and letters (that is,1-A-2-B-3-C, and so forth). This study chose the time taken to complete Trail (B–A)as the index of set-shifting ability.
Verbal working memory: Digit span test. This is a subtest of the Chinese-Wechsler Intelligence Scale for Children (Gong & Cai, 1993). The number of thelongest chain of digits is counted as the raw score.
Planning: Tower of Hanoi (ToH). The Chinese version of the ToH(Kopecky, Chang, Klorman, Thatcher, & Borgstedt, 2005) consists of a flat,varnished wooden rectangular base (26� 8.5� 2 cm). Three wooden posts of equalheight (13 cm) and diameter (1 cm) are attached to the base. Vertical pegs are placedan equal distance apart (8 cm). On the posts are four circular wooden disks, rangingin size from small to large (4, 4.5, 5, and 6 cm), with a 1-cm hole in the center toallow them to be positioned on the posts. The ToH requires participants totransform an arrangement of disks into a different configuration in as few moves aspossible. The total time to complete the ToH was then used to determine theplanning function of the participants.
Chinese-Wechsler Intelligence Scale for Children (C-WISC). TheIntelligence Quotient (IQ) of the participants was assessed using the Chinese-Wechsler Intelligence Scale for Children (C-WISC) (Gong & Cai, 1993), a revisedversion of the Wechsler Intelligence Scale for Children third edition (WISC-III)(Weschler, 1991). The C-WISC is the most widely used individually administered
800 YING QIAN ET AL.
Dow
nloa
ded
by [
b-on
: Bib
liote
ca d
o co
nhec
imen
to o
nlin
e U
C]
at 1
4:51
03
Nov
embe
r 20
13
measure of intelligence for children and adolescents in Asian societies. It contains11 subtests and calculates an age-corrected full-scale IQ. The C-WISC hasproven construct validity, with criterion validity correlation coefficients rangingfrom 0.76 to 0.96.
Procedure
The diagnostic group were recruited from the outpatients who were suspectedto be suffering from ADHD when they came to our hospital for the first time, andthe healthy controls were recruited from students studying at the two regularelementary schools in Beijing. It was arranged that they would take the recruitingexamination within 1 to 2 weeks after they received the notice to attend this study.All the participants were given a general introduction to the study and theopportunity to ask questions about it. Once they showed a full understanding of theaims of the study, the participants and their parents signed an informed consentform before testing began. The study protocol was approved by the ethicscommittee of the Institute of Mental Health, Peking University.
On the day of the appointment, all the children (including outpatients andcontrols) took part in the performance-based EF and IQ tests, during which timetheir parents completed the BRIEF or were interviewed by a doctor using the CDIS(for screening) and ADHD RS-IV (for assessment of symptom severity). During the3-hour appointment, the children were allowed to play with toys or read comicswhen they became tired.
The executive function tasks and IQ tests were conducted by seven trainedgraduate students. Each student had been thoroughly trained and had at least3 months’ experience in administering the tests. They followed the guidelines foreach subtest, and thus the Kappa value (inter-rater agreement) was acceptable(0.70–0.75). To minimize context interference, the children were tested individuallyin separate quiet rooms in the hospital (patients) or school (controls).
Two steps were taken to diagnose the patients. First, on the day of therecruiting examination, to determine whether the participants met the CDIS criteriaaccording to the DSM-IV the parents were interviewed separately by twopsychiatrists, one of whom was a senior psychiatrist. Those who were verified asnormal according to CDIS received the results of all the tests by mail, while forthose who were verified as suspected patients it was arranged for them to return toour hospital another time for final diagnosis. Second, as it took several days togather the results of the examinations, both the potential patients and their parentsneeded to come to the hospital 3–7 days later for medical advice. At the next visitthe chief doctor made the final diagnosis based on DSM-IV according to clinicalobservation and the result of the CDIS.
Data analysis
The sample was initially examined for normality. Logistic transformation wasapplied to the Trail (B–A) time and total time and errors for the ToH variables tocorrect for skewness. Multivariate analysis of variance (MANOVA) was performed
EXECUTIVE FUNCTION DEFICITS AND ADHD 801
Dow
nloa
ded
by [
b-on
: Bib
liote
ca d
o co
nhec
imen
to o
nlin
e U
C]
at 1
4:51
03
Nov
embe
r 20
13
to assess the effect of diagnostic group (ADHD, ADHDþODD, control) on the
various executive function tests and the BRIEF. Given that age, gender,
symptom severity, subtype of ADHD, and IQ may affect measures of executive
function—Cronbach’s coefficients between indexes of executive function and age
were 0.052–0.377, p5 .05; those between indexes of executive function and
gender, symptom, subtype, IQ were 0.050–0.121, 0.198–0.443, 0.023–0.527, and
0.008–0.425, respectively; p5 .05—MANOVAs were run with age, gender, full
ADHD RS-IV score, and full IQ score as covariates. To exclude the influence of the
subtype of ADHD, the MANOVAs were re-run with age, gender, full ADHD
RS-IV score, and full IQ score as covariates both among the ADHD-I, ADHD-
IþODD, and control groups and among the ADHD-C, ADHD-CþODD, and
control groups.Because of the multiple comparisons, a more conservative approach to
interpretation was applied to avoid Type I error, and the results were interpreted as
significant at the p5 .01 level instead of p5 .05.
RESULTS
Group comparison of performance-based tests of executive function
The results for group differences among ADHD, ADHDþODD, and
Control were as follows. First, both the ADHDþODD and ADHD groups
demonstrated worse performance than the control group in inhibition (Stroop (4–2)
time, F(2, 252)¼ 8.320, p5 .01, Z2¼ 0.069) and set shifting (Trail, B–A) time,
F(2, 252)¼ 11.500, Z2¼ 0.084, p5 .01), but no significant difference was found
between the ADHDþODD and ADHD groups in these areas. Second, there were
no significant differences among the ADHD, ADHDþODD, and control groups
for the backward digit number and total ToH time tests (see Table 3).These results persisted regardless of whether MANOVAs were performed
among the ADHD-I, ADHD-IþODD, and control groups or among the ADHD-
C, ADHD-CþODD, and control groups.
Group comparison of behavioral rating of executive function
A MANOVA with all eight subscales of the BRIEF as dependent variables
showed that both the ADHD and ADHDþODD groups were rated higher by
the parents in executive function on all eight subscales of the BRIEF,
F(2, 252)¼ 28.487–133.113, p5 .01, Z2¼ 0.175–0.509, than the control group.
Further, the ADHDþODD group received a higher parent rating on the inhibition
( p5 .01), shifting ( p5 .01), and emotional control ( p5 .01) subscales than the
ADHD group (see Table 3).There were no changes in the results when MANOVAs were performed
among the ADHD-I, ADHD-IþODD, and control groups, or among the ADHD-
C, ADHD-CþODD, and control groups.
802 YING QIAN ET AL.
Dow
nloa
ded
by [
b-on
: Bib
liote
ca d
o co
nhec
imen
to o
nlin
e U
C]
at 1
4:51
03
Nov
embe
r 20
13
Table3
Mean(SD)perform
ance
oftheADHD,ADHDþODD,andcontrolgroupsin
theperform
ance-basedtestsandtheBehaviorRatingInventory
ofExecutive
Function
ADHD
ADHDþODD
Control
n¼89
n¼53
n¼116
Mean
SD
Mean
SD
Mean
SD
F(2,252)
Partialeta
squared
pADHD
vsControl
pADHDþODD
vsControl
pADHDþODD
vsADHD
Inhibition
Stroop4-2t
28.876
14.090
27.000
10.376
22.793
10.203
8.320**
.069
5.001
.009
.248
Shift
Ln(TrailB-A
)4.864
0.073
4.769
0.095
4.379
0.064
11.500**
.084
5.001
.001
.427
Workingmem
ory
Back
digit
4.350
1.706
4.300
1.295
4.630
1.335
0.392
.031
.175
.179
.855
Plan
Ln(ToH
time)
5.086
0.617
4.956
0.706
5.012
0.735
0.448
.008
.515
.672
.361
BRIE
F
Inhibit
1.765
0.462
2.066
0.425
1.265
0.254
96.731**
.430
5.001
5.001
5.001
Shift
1.466
0.300
1.679
0.314
1.314
0.281
28.487**
.175
5.001
5.001
5.001
Emotionalcontrol
1.529
0.369
1.902
0.411
1.318
0.300
50.940**
.280
5.001
5.001
5.001
Initiate
1.847
0.357
1.917
0.371
1.455
0.333
46.525**
.258
5.001
5.001
.245
Workingmem
ory
2.230
0.362
2.223
0.397
1.479
0.355
133.113**
.494
5.001
5.001
.904
Plan
2.261
0.348
2.333
0.359
1.586
0.382
117.981**
.479
5.001
5.001
.257
Organization
2.390
0.477
2.431
0.474
1.741
0.498
59.541**
.335
5.001
5.001
.625
Monitor
2.466
0.377
2.587
0.327
1.754
0.390
133.044**
.509
5.001
5.001
.063
Stroop4-2t¼timetaken
tocomplete
Stroop4minusthattaken
tocomplete
Stroop2;Ln(TrailB-A
)¼LN
(tim
etaken
tocomplete
trailB
minustimetaken
to
complete
trailA);Ln(ToH
time)¼LN
(totaltimetaken
tocompeteTower
ofHanoi);ODD¼Oppositional-defiantdisorder;ADHD¼Attentiondeficithyperactivity
disorder;BRIE
F¼BehaviorRatingInventory
ofExecutiveFunction;*¼p5
.05;**¼p5
.01.
EXECUTIVE FUNCTION DEFICITS AND ADHD 803
Dow
nloa
ded
by [
b-on
: Bib
liote
ca d
o co
nhec
imen
to o
nlin
e U
C]
at 1
4:51
03
Nov
embe
r 20
13
DISCUSSION
ADHD, ADHDþODD, versus control
Although previous cross-cultural studies have reported that children withADHD are less hyperactive and impulsive and have less comorbid condition ofODD in Han Chinese (28.2%) (Yang et al., 2001) than in Caucasian samples(54–67%) (Barkley et al., 1990), the result of the current cross-cultural study onexecutive function replicated what most previous studies found in Westerncounterparts (Clark et al., 2000; Nigg et al., 1998; Oosterlaan et al., 1998). TheADHD groups, with or without ODD, performed significantly worse thanthe control group in some of the performance-based tests—a longer reaction timefor the Stroop (4–2) and Trail (B–A) tests—and also on the ecologically validmeasure (higher scores for all eight subscales of the BRIEF) in the current HanChinese sample. Such a finding might indicate that executive dysfunction isrelatively robust in children with ADHD across cultures. This might also strengthenthe theory that executive dysfunction is one of the core deficits in children withADHD. Furthermore, the present study supports the first hypothesis that childrenwith ADHD, both on its own and comorbid with ODD, display executivedysfunction on both performance-based tests and ecologically valid measures.
However, on the performance-based tests, the majority of previous studieshave reported considerable impairment in working memory in children with ADHD(Seidman, 2006; Willcutt et al., 2005), whereas in this study only deficits ininhibition and shifting were observed. Differences in the instruments used tomeasure working memory may explain the inconsistency between the current studyand the previous ones. Most studies using the self-order pointing (SOP) task orother space span tests as the instrument to measure working memory have reportedchildren with ADHD to display impairment in working memory (Sergeant, Geurts,& Oosterlaan, 2002; Willcutt et al., 2005), whereas only half of the studies usingverbal working memory assessments reported positive results (Willcutt et al., 2005).This study used the digit span test (a verbal working memory test) as the instrument.Alternatively, the inconsistency between this study and many of the previousstudies may indicate either that children with ADHD have more severe deficitsin spatial working memory than in verbal working memory, or that the digitspan test is insufficiently sensitive to detect working memory deficits in childrenwith ADHD.
On the other hand, for the performance-based tests, unlike the results of someprevious studies (Toplak et al., 2009; Willcutt et al., 2005), the current study did notfind children with ADHD were impaired in planning. As there have also been quitea few studies (Geurts, Vert, Oosterlaan, Roeyers, & Sergeant, 2005; Sergeant et al.,2002) reporting no such an impairment in planning in children with ADHD, wemight speculate that the impairment in planning in children with ADHD is not asrobust as that found in inhibition (Seidman, 2006).
As described in the introduction, other studies have been unable to detect anyexecutive dysfunction at all in children with ADHD or ADHDþODD. Thesenegative findings may be attributable to several factors, including a small samplesize (Stephanie et al., 2004; Van et al., 2005), the absence of a clinical group
804 YING QIAN ET AL.
Dow
nloa
ded
by [
b-on
: Bib
liote
ca d
o co
nhec
imen
to o
nlin
e U
C]
at 1
4:51
03
Nov
embe
r 20
13
(Van et al., 2005), and lack of control for CD or other comorbidities (Schachar &Logan, 1990; Schachar et al., 2000; Stephanie et al., 2004; Van et al., 2005).
ADHD versus ADHDþODD
In this study the ADHDþODD group were rated worse than the ADHDgroup by their parents on the ecologically valid measure (with higher scores on theinhibition, shift, and emotional control subscales of the BRIEF) but performedsimilarly to the ADHD group in the performance-based tests. These findingssupport the second hypothesis that children with ADHDþODD display moresevere executive dysfunction than those with ADHD on everyday executivefunction only.
As for the performance-based tests, the results confirm the findings of mostprevious studies (Oosterlaan et al., 1998) that the executive function of children withADHDþODD is similar to that of children with ADHD only. However, a previousstudy conducted by our group (Shuai & Wang, 2007) showed that the executivefunction of children with ADHDþODD/CD was worse than that of normalcontrols and significantly better than that of children with pure ADHD. Severalfactors may explain this inconsistency. Our previous study used the Stroop 4 time todetect response inhibition, which is not as sensitive as the Stroop (4–2) time, as thelatter excludes interference by baseline color-naming ability. Alternatively, the smallsample size (n¼ 19) and failure to control for other comorbidities in our previousstudy might explain why it could not be replicated by the current study.As mentioned in the introduction, unlike the present study and most previousstudies, there have also been studies that have returned findings that the executivefunction of children with ADHDþODD/CD is significantly better or worse thanthat of children with ADHD only (Schachar et al., 2000; Van et al., 2005). However,as these studies either included CD and ODD as one group or did not control forother comorbidities, their results may not be sufficient to show the influence of theco-occurring condition of ODD only on ADHD.
On everyday executive function, the results for the ecologically valid measurein this study are in partial agreement with those of previous research, in that nosignificant difference was found between the ADHD and ADHDþODD groups inthe monitor and plan/organize subscales of the BRIEF. In particular, both theresults of this study and that of the only other study (Clark et al., 2000) in this fieldusing ecologically valid instruments (Six Elements Test and Hayling SentenceCompletion Test) showed that adolescents with ADHD display deficits in executivefunction similar to those of adolescents with ADHDþODD/CD, specifically intheir ability to generate strategies and monitor their ongoing behavior. However,this study further found that the ADHDþODD group were rated similarly to theADHD group in the working memory, plan/organize, and initiate subscales, butworse in the inhibition, shift, and emotion control subscales of the BRIEF. Unlikethe BRIEF, which touches all eight constructs of executive function, the SixElements Test (Burgess et al., 1996) and Hayling Sentence Completion Test(Burgess & Shallice, 1996) used in previous studies mainly focus on the monitor andplan constructs. Thus the only partial agreement between this study and that ofClark et al. (2000) is due to the latter measures failing to address the other
EXECUTIVE FUNCTION DEFICITS AND ADHD 805
Dow
nloa
ded
by [
b-on
: Bib
liote
ca d
o co
nhec
imen
to o
nlin
e U
C]
at 1
4:51
03
Nov
embe
r 20
13
constructs of executive function. The results of this study thus provide moremeaningful information on the executive dysfunction of children with ADHD andODD, such as more severe deficits in inhibition, shifting, and emotion control.
The results of performance-based tests conflict with those of ecologically validmeasures of executive function for the sample, in that the ADHDþODD groupwas found to be similar to the ADHD group in the performance-based tests, but todisplay worse performance than the ADHD group on everyday executive functionon the three subscales of the BRIEF. This inconsistency has also been found inother ADHD studies. Riccio et al. (2006) found no differences in laboratory tasks,although parent reports using the BRIEF indicated different problems betweenchildren with different subtypes of ADHD. Toplak et al. (2009) found throughlogistic regression analyses that when both child performance on stop task and theparent and teacher BRIEF ratings were entered as predictors, only the parent andteacher ratings emerged as predictors of ADHD status. These results suggest thatperformance-based tests may revise what is known about the child, but may notaccurately reflect what others see in daily contexts (Riccio et al., 2006). That is tosay, ADHDþODD children may be described as displaying severe executivedysfunction in everyday activities by their parents, even though such dysfunctionmay not be shown during performance-based tests conducted under observation(Gioia & Isquith, 2004). This phenomenon can be explained as follows. Childrenwith ADHDþODD can perform normally in conventional performance-basedexecutive function tests because the situations are highly structured, the rules areexplicit, and the consequences are short term (Draeger et al., 1986). However, theymay not have the ability to deal with multi-step tasks in real life, because these tasksrequire a more complicated series of responses (Chan et al., 2008a, 2008b).Alternatively, the phenomenon may be attributable to the different levels ofexecutive function that the different instruments measure (Chan et al., 2008a).
Limitations and implications
The comparison of executive function between diagnostic groups in this studyrevealed that the participants with ADHD and ODD who displayed the same levelof performance as those with ADHD in performance-based tests may have hadgreater difficulties in some domains of executive function in their everyday lives.These findings can give us important clinical implications: (i) There is dissociationbetween test performance and ecologically parent rating, so it is important tocombine both performance-based tests and ecologically valid instruments to give amore comprehensive and detailed investigation of the different levels of executivefunction. (ii) The children with ADHDþODD will have more difficulties in theireveryday life than those with ADHD only, since poorer executive function isassociated with higher risk of grade retention and decreased academic achievement.(iii) Clearly, more attention needs to be paid to improving the everyday performanceof children with ADHDþODD in inhibition, shifting, and emotional control.It would be of value to apply these findings in clinical work.
This study has several limitations. First, although the behavior that theparents rated on the BRIEF was commonly associated with the executivedysfunction of the participants, it may in some instances have been higher because
806 YING QIAN ET AL.
Dow
nloa
ded
by [
b-on
: Bib
liote
ca d
o co
nhec
imen
to o
nlin
e U
C]
at 1
4:51
03
Nov
embe
r 20
13
of the unwillingness of some of the participants to perform certain tasks on theBRIEF, such as following multi-step tasks, which is not uncommon among childrenwith ODD. Second, parents tend to rate children with ODD as impaired on nearlyall types of parent ratings (not just executive function), simply because thesechildren have annoying and aggressive behaviors. So the difference between ADHDand ADHDþODD groups might be due only to the dissociation between parentrating and test performance. Thus future studies could include other ecologicallyvalid tests that simulate real life but are observed by trained observers to excludechildren unwilling to perform the tasks in the performance-based tests and toexclude the subjectivity of parents on the scale. Third, it might be the Han Chineseculture that would make parents more likely to rate children with annoying oroppositional behaviors as having greater executive dysfunction. Thus future studiescould pay more attention to cross-culture influence. Finally, the sample wasdominated by boys and thus the findings may not be sufficiently powerful to detectany gender effects. Hence future studies could include more girls to detectgender effects.
Notwithstanding these limitations, the current study has indicated that HanChinese children with ADHD display executive dysfunction in performance-basedtests and everyday life scenarios, just as has been found in Western counterparts.However, children with co-occurring ADHD and ODD show more severe executivedysfunction in everyday life scenarios than those with ADHD alone.
ACKNOWLEDGMENTS
This research is funded by Ministry of Health grants (200802073)and Ministry of Science and Technology grants (2007BA117B03). We thank theanonymous reviewers for their advice and comments as well as the individuals whoserved as research participants.
REFERENCES
Abikoff, H., Courtney, M., Pelham, W. E., & Koplewicz, H. S. (1993). Teachers’ ratings ofdisruptive behaviors: The influence of halo effects. Journal of Abnormal Child
Psychology, 21(5), 519–533.American Psychiatric Association (1994). Diagnostic and statistical manual of mental disorders
(4th ed.). Washington, DC: American Psychiatric Association.
Aronowitz, B., Liebowitz, M., Hollander, E., Fazzini, E., Durlach-Misteli, C., Frenkel, M.,et al. (1994). Neuropsychiatric and neuropsychological findings in conduct disorder andattention-deficit hyperactivity disorder. Journal of Neuropsychiatry and Clinical
Neuroscience, 6(3), 245–249.Barkley, R. A. (1998). Attention-deficit hyperactivity disorder: A clinical workbook (2nd ed.).
New York: Guilford Press.Barkley, R. A., DuPaul, G. J., & McMurray, M. B. (1990). Comprehensive evaluation of
attention deficit disorder with and without hyperactivity as defined by research criteria.Journal of Consulting and Clinical Psychology, 58(6), 775–789.
Biederman, J., Monuteaux, M. C., Doyle, A. E., Seidman, L. J., Wilens, T. E., Ferrero, F.,
et al. (2004). Impact of executive function deficits and attention-deficit/hyperactivity
EXECUTIVE FUNCTION DEFICITS AND ADHD 807
Dow
nloa
ded
by [
b-on
: Bib
liote
ca d
o co
nhec
imen
to o
nlin
e U
C]
at 1
4:51
03
Nov
embe
r 20
13
disorder (ADHD) on academic outcomes in children. Journal of Consulting and ClinicalPsychology, 72(5), 757–766.
Biederman, J., Newcorn, J., & Sprich, S. (1991). Comorbidity of attention deficithyperactivity disorder with conduct, depressive, anxiety, and other disorders.American Journal of Psychiatry, 148(5), 564–577.
Burgess, P. W., Alderman, N., Evans, J. J., Wilson, B. A., Emslie, H., & Shallice, T. (1996).Modified six elements test. In B. A. Wilson, N. N. Alderman, P. W. Burgess, H. Emslie,& J. J. Evans (Eds.), Behavioural assessment of the dysexecutive syndrome. Bury St.
Edmunds, UK: Thames Valley Test Company.Burgess, P. W., & Shallice, T. (1996). Response suppression, initiation and strategy use
following frontal lobe lesions. Neuropsychologia, 34(4), 263–272.
Castellanos, F. X., & Tannock, R. (2002). Neuroscience of attention-deficit/hyperactivitydisorder: the search for endophenotypes. Nature Reviews Neuroscience, 3(8), 617–628.
Chan, R. C., Shum, D., Toulopoulou, T., & Chen, E. Y. (2008a). Assessment of executivefunctions: Review of instruments and identification of critical issues. Archive of Clinical
Neuropsychology, 23(2), 201–216.Chan, R. C., Wang, Y., Ma, Z., Hong, X. H., Yuan, Y., Yu, X., et al. (2008b). Objective
measures of prospective memory do not correlate with subjective complaints in
schizophrenia. Schizophrenia Research, 103(1–3), 229–239.Christensen, A., Margolin, G., & Sullaway, M. (1992). Interparental agreement on child
behavior problems. Psychological Assessment, 4(4), 419–425.
Clark, C., Prior, M., & Kinsella, G. J. (2000). Do executive function deficits differentiatebetween adolescents with ADHD and oppositional defiant/conduct disorder? Aneuropsychological study using the six elements test and Hayling sentence completiontest. Journal of Abnormal Child Psychology, 28(5), 403–414.
Clark, C., Prior, M., & Kinsella, G. (2002). The relationship between executive functionabilities, adaptive behaviour, and academic achievement in children with externalisingbehaviour problems. Journal of Child Psychology and Psychiatry, 43(6), 785–796.
Connor, D. F., & Doerfler, L. A. (2007). Adhd with comorbid oppositional defiant disorderor conduct disorder: Discrete or nondistinct disruptive behavior disorders? Journal ofAttention Disorders, 12(2), 126–134.
Coolidge, F. L., Thede, L. L., & Young, S. E. (2000). Heritability and the comorbidityof attention deficit hyperactivity disorder with behavioral disorders and executivefunction deficits: A preliminary investigation. Developmental Neuropsychology, 17(3),
273–287.Draeger, S., Prior, M., & Sanson, A. (1986). Visual and auditory attention performance in
hyperactive children: Competence or compliance. Journal of Abnormal Child Psychology,14(3), 411–424.
DuPaul, G. J., Power, T. J., Anastopoulos, A. D., & Reid, R. (1998). ADHD Rating Scale-IV:Checklists, norms, and clinical interpretations. New York: Guilford Press.
Geurts, H. M., Vert, S., Oosterlaan, J., Roeyers, H., & Sergeant, J. A. (2005). ADHD
subtypes: Do they differ in their executive functioning profile? Archives of ClinicalNeuropsychology, 20(4), 457–477.
Gioia, G. A., & Isquith, P. K. (2004). Ecological assessment of executive function in
traumatic brain injury. Developmental Neuropsychology, 25(1–2), 135–158.Gioia, G. A., Isquith, P. K., Guy, S. C., & Kenworthy, L. (2000). Behavior rating inventory of
executive function. Odessa, FL: Psychological Assessment Resources.
Gong, Y. X., & Cai, T. S. (1993). Manual of Wechsler Intelligence Scale for Children, Chineserevision (C-WISC). Changsha, China: Hunan Map Press.
Kopecky, H., Chang, H. T., Klorman, R., Thatcher, J. E., & Borgstedt, A. D. (2005).Performance and private speech of children with attention-deficit/hyperactivity disorder
808 YING QIAN ET AL.
Dow
nloa
ded
by [
b-on
: Bib
liote
ca d
o co
nhec
imen
to o
nlin
e U
C]
at 1
4:51
03
Nov
embe
r 20
13
while taking the Tower of Hanoi test: Effects of depth of search, diagnostic subtype, andmethylphenidate. Journal of Abnormal Child Psychology, 33(5), 625–638.
Mahone, E. M., & Hoffman, J. (2007). Behavior ratings of executive function amongpreschoolers with ADHD. The Clinical Neuropsychologist, 21(4), 569–586.
Nigg, J. T., Hinshaw, S. P., Carte, E. T., & Treuting, J. J. (1998). Neuropsychological
correlates of childhood attention-deficit/hyperactivity disorder: Explainable by comor-bid disruptive behavior or reading problems? Journal of Abnormal Child Psychology,107(3), 468–480.
Oosterlaan, J., Logan, G. D., & Sergeant, J. A. (1998). Response inhibition in ADHD, CD,comorbid ADHDþCD, anxious, and control children: A meta-analysis of studies withthe stop task. Journal of Child Psychology and Psychiatry, 39(3), 411–425.
Qian, Y., & Wang, Y. F. (2007). [Reliability and validity of behavior rating scale of executivefunction parent form for school age children in China]. Beijing Da Xue Xue Bao, 39(3),277–283.
Reitan, R. M. (1979). Manual for administration of neuropsychological test batteries for adults
and children. Tucson, AZ: Neuropsycological Press.Riccio, C. A., Homack, S., Jarratt, K. P., & Wolfe, M. E. (2006). Differences in academic and
executive function domains among children with ADHD predominantly inattentive and
combined types. Archives of Clinical Neuropsychology, 21(7), 657–667.Schachar, R., & Logan, G. D. (1990). Impulsivity and inhibitory control in normal
development and childhood psychopathology. Developmental Psychology, 26(5),
710–720.Schachar, R., Mota, V. L., Logan, G. D., Tannock, R., & Klim, P. (2000). Confirmation of
an inhibitory control deficit in attention-deficit/hyperactivity disorder. Journal ofAbnormal Child Psychology, 28(3), 227–235.
Seidman, L. J. (2006). Neuropsychological functioning in people with ADHD across thelifespan. Clinical Psychology Review, 26(4), 466–485.
Sergeant, J. A., Geurts, H., & Oosterlaan, J. (2002). How specific is a deficit of executive
functioning for attention-deficit/hyperactivity disorder? Behavior Brain Research,130(1–2), 3–28.
Shallice, T., & Burgess, P. W. (1991). Deficits in strategy application following frontal lobe
damage in man. Brain, 114(Pt 2), 727–741.Shuai, L., & Wang, Y. F. (2007). Executive function characteristic in boys with attention
deficit hyperactivity disorder comorbid disruptive behavior disorders. Beijing Da Xue
Xue Bao, 39(3), 241–246.Stephanie, H. M., van Goozen, P. T., & Cohen-Kettenis, H. S. (2004). Executive functioning
in children: A comparison of hospitalised ODD, ODDþADHD, normals. Journal ofChild Psychology and Psychiatry, 45(2), 284–292.
Stroop, J. R. (1935). Studies of interference in serial verbal reactions. Journal of ExperimentalPsychology, 18(6), 643–662.
Toplak, M. E., Bucciarelli, S. M., Jain, U., & Tannock, R. (2009). Executive functions:
Performance-based measures and the Behavior Rating Inventory of Executive Function(BRIEF) in adolescents with attention deficit/hyperactivity disorder (ADHD). ChildNeuropsychology, 16, 1–20.
Van, M. J., Marzocchi, G. M., & De, M. T. (2005). Response inhibition and attention deficithyperactivity disorder with and without oppositional defiant disorder screened from acommunity sample. Developmental Neuropsychology, 28(1), 459–472.
Wechsler, D. (1991). Wechsler Intelligence Scale for Children, third edition (WISC-III)manual. San Antonio, TX: The Psychological Corporation.
Welsh, M. C., & Pennington, B. F. (1988). Assessing frontal lobe functioning in children:Views from developmental psychology. Developmental Neuropsychology, 4, 199–230.
EXECUTIVE FUNCTION DEFICITS AND ADHD 809
Dow
nloa
ded
by [
b-on
: Bib
liote
ca d
o co
nhec
imen
to o
nlin
e U
C]
at 1
4:51
03
Nov
embe
r 20
13
Willcutt, E. G., Doyle, A. E., Nigg, J. T., Faraone, S. V., & Pennington, B. F. (2005). Validityof the executive function theory of attention-deficit/hyperactivity disorder: A meta-analytic review. Biological Psychiatry, 57(11), 1336–1346.
Wodka, E. L., Loftis, C., Mostofsky, S. H., Prahme, C., Larson, J. C., Denckla, M. B., et al.(2008). Prediction of ADHD in boys and girls using the D-KEFS. Archives of ClinicalNeuropsychology, 23(3), 283–293.
Yang, L., Wang, Y. F., Qian, Q. J., & Gu, B. M. (2001). Primary exploration of the clinicalsubtypes of attention deficit hyperactivity disorder in Chinese children. Clinical Journalof Psychiatry, 34(4), 204–207.
810 YING QIAN ET AL.
Dow
nloa
ded
by [
b-on
: Bib
liote
ca d
o co
nhec
imen
to o
nlin
e U
C]
at 1
4:51
03
Nov
embe
r 20
13
