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Research Article                                                                                                                     Open Access

## How Prevalent Are Autistic Traits Among Children With AttentionDeficit/Hyperactivity Disorder? A Qualitative Review of  the Literature

Mai Uchida, MD 1, 2, 3 , Stephen V. Faraone, PhD 4 , Gagan Joshi, MD 1, 2, 3 , Andrea Spencer, MD 1, 2, 3 , Tara Kenworthy, BA 1 , K. Yvonne Woodworth, BA 1 , and Joseph Biederman, MD 1, 2, 3*

1 Massachusetts General Hospital, Department of Psychiatry, Pediatric Psychopharmacology Unit 2 Massachusetts General Hospital, Department of Psychiatry, Alan & Lorraine Bressler Center 3 Harvard Medical School, Department of Psychiatry

4 SUNY Upstate Medical University, Departments of Psychiatry and of Neuroscience and Physiology

* Corresponding Author:

jbiederman@partners.org

## Abstract

Background: Twin, family, and linkage studies have indicated that attention-deficit/hyperactivity disorder (ADHD) and autism spectrum disorders (ASDs) share a portion of  their heritable etiology. This suggests that individuals with ADHD may manifest different forms of  ASDs that may range from fully developed syndromic forms of the disorder to milder manifestations of ASD symptomatology, which will henceforth be referred to as autistic traits.

Objective: The main purpose of this study was to conduct a literature search to examine the current body of  knowledge regarding the prevalence of  autistic traits (operationalized as the presence of  autistic symptoms in the absence of  a diagnosis of  ASD) among children with ADHD and the associated morbidity of such traits.

Method: A  systematic literature search in  PubMed was conducted to discover all controlled studies published in the English language that systematically assessed the presence of  autistic traits in children with ADHD who did not meet the criteria for ASDs. Three articles met our inclusion and exclusion criteria and were included in this qualitative review.

Results: Only  three  scientific  papers  that  met  our  a  priori  inclusion  and  exclusion  criteria  were  identified.  These  articles  described findings obtained from clinical samples and identified a prevalence of  autistic traits among children with ADHD that ranged from 7% to 60%. As compared with children with ADHD without these traits, the presence of autistic traits in children with ADHD was associated with more severe dysfunction in a wide range of  non-overlapping domains and in the social and communication domains in particular.

Conclusions: Although this study was limited by the small amount of  available literature about this subject, these findings suggest that a sizeable subset of  children with ADHD manifest autistic traits and that the presence of  these traits is associated with increased dysfunction and social and communication deficits.

Key Words: Autism; Autistic traits; ADHD; review

## Introduction

Twin,  family,  and  linkage  studies  indicate  that  attention-deficit/hyperactivity  disorder  (ADHD)  and  autism  spectrum  disorders  (ASDs)  share  a  portion  of their  heritable  etiology  (1-6).  Genome-wide  association  studies  found  rare  copy  number  variants  that were shared between the two disorders (7). This state of affairs would suggest that individuals with ADHD may manifest different forms of  ASDs that may range from fully developed syndromatic forms of the disorder to milder forms of ASD symptomatology, which will  henceforth  be  referred  to  as autistic  traits. However,  in  contrast  with  the  well-developed  literature regarding  the  overlap  of   ADHD  and  syndromatic ASD, much less is known about whether children with ADHD exhibit autistic traits and whether such symptoms  are  associated  with  unique  morbidity  and  dysfunction.

A  better  understanding  of  whether  children  with ADHD exhibit autistic traits and whether such traits are  associated  with  dysfunction  and  morbidity  has important  implications. Clinically,  such  knowledge may  encourage  the  development  of  individualized treatment approaches to help address these problems. Scientifically, such knowledge can help with the identification of  a more homogeneous subgroup of children with ADHD with a unique neurobiological underpinning.

The main aim of this study was to examine the current body of knowledge regarding the prevalence of autistic  traits  among  children  with  ADHD  and  the associated  morbidity  of   such  traits.  To  this  end,  we conducted  a  literature  search  and  examined  studies that assessed autistic traits in children with ADHD in the  absence  of   syndromatic  levels  of   ASD.  Related aims were to inventory the conceptualization of  autistic traits and the methods used to assess them. To the best  of   our  knowledge,  this  is  the  first  systematic review that examined the prevalence of  autistic traits among  children  with  ADHD  who  do  not  meet  the criteria for ASDs.

## Methods

We conducted a comprehensive search of the scientific  literature  using  the  following  PubMed  search criteria: (ADHD[Title] OR 'attention deficit hyperactive  disorder'[Title]  OR  autism[Title]  OR  'autistic traits'[Title] OR autistic[Title] OR 'autism traits'[Title] OR 'autistic spectrum disorder traits'[Title] OR 'autism spectrum disorder traits'[Title])  AND  (('autism  traits'[All  Fields]  OR 'autistic traits'[All Fields] OR autistic[All Fields] OR

'autistic  spectrum  disorder  traits'[All  Fields])  AND (ADHD[All Fields] OR 'attention deficit hyperactivity disorder'[All Fields])). If  the reference sections of the articles that were found suggested any additional articles, these were also examined.

For inclusion in the review, we restricted the PubMed literature to studies that included the following: 1) operationalized diagnosis of ADHD; 2) operationalized assessment of autistic traits; 3) operationalized assessment  of   ASD  to  ensure  that  subjects  did  not meet  one  of   the  ASD  diagnoses;  4)  availability  of healthy controls for comparison; and 5) provision of the  prevalence  of   autistic  traits  among  the  children with ADHD. The requirement of having healthy controls  was  to  examine  if   the  autistic  traits  were  overrepresented among the children with ADHD as compared with general population rates. Articles that were written  in  non-English  languages,  articles  that  were not peer reviewed, and review articles were excluded. Four  child  psychiatrists  and  one  psychologist  examined the identified articles and evaluated their eligibility.

We extracted the following methodological features from  each  article:  1)  study  sample  size;  2)  proband mean age; 3) the diagnostic system used to make diagnoses  and  the  method  of   diagnoses;  4)  inclusion and exclusion criteria; 5) study measures; 5) the definition of  autistic traits; and 6) the prevalence of  autistic traits among the children with ADHD.

## Results

From  the  initial  database  search,  393  papers  were identified  and  screened by  one psychologist  and one child and adolescent psychiatrist. After the screening, 25 articles  were  identified  as  possibly  being  relevant, and their full text was carefully examined. Of  these 25 articles, 22 were excluded for the following reasons: 1) 5 did not report the prevalence of autistic traits in the ADHD  probands;  2)  12  did  not  exclude  the  ASD diagnoses; 3) 4 were reviews; and 4) one was a validation  study  of   the  Social  Responsiveness  Scale  (SRS) (8).  Thus,  only  three  studies  met  our  inclusion  and exclusion criteria and were included in this qualitative review (4;9;10).

Table  1  lists  the  characteristics  of   each  study,  including its  design  and  its  definition  of   autistic  traits. There  were  926  children  with  ADHD  that  were evaluated by these studies. The studies used five different  measures  to  assess  autistic  traits;  details  of individual  studies  are  provided  in  the  following  sections of  this article.

Table 1. Study characteristics, assessment and measurement methods, design, and prevalence of  autistic traits among children with attention-deficit/hyperactivity disorder

| Study                    | Total no. of subjects per group             | Age               | Autism spectrum disorder diagnosis as exclusion?   | Diagnostic system and method                                                                                                                                                                        | Measures                                                                                                                            | Definition of autistic traits                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
|--------------------------|---------------------------------------------|-------------------|----------------------------------------------------|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|-------------------------------------------------------------------------------------------------------------------------------------|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| Grzadzinski et al., 2011 | 144 (ADHD group = 75; control group = 69)   | 7.1 to 17.8 years | Yes                                                | Schedule of Affective Disorders and Schizo- phrenia for Children - Present and Lifetime Version (K-SADS-PL) was used to confirm a DSM-IV diagnosis.                                                 | Social Responsiveness Scale Children's Communication Checklist-2                                                                    | 1. Total Social Responsiveness Scale T score of ≥60 2. Children's Communication Checklist-2 autism spectrum disorder profile: General Communication Composite score of <55 with a negative Social Interaction Deviance Composite score or a Social Interaction Deviance Composite score of <- 15 regardless of General Communication Composite score 3. Meets criteria of both 1 and 2 as listed here                                                                                                                                                                                                                  |
| Kochhar et al., 2011     | 60 (ADHD group = 30; control group = 30)    | 9 to 15 years     | Yes                                                | Development and Well- Being Assessment (DAWBA ) was re- viewed by at least 2 child psychiatrist to confirm a DSM-IV diagnosis.                                                                      | Social Aptitudes Scale (part of the Development and Well-Being Assessment) Lifetime version of Social Communication Question- naire | 1. Social Aptitudes Scale score of ≤12 2. Social Communication Questionnaire score of ≥15                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
| Mulligan et al., 2009    | 970 (ADHD group = 821; control group = 149) | 5 to 17 years     | Yes                                                | Parental Account of Children's Symptoms ( PACS interview), Strengths and Difficul- ties Questionnaire (SDQ) and Connor's parent and teacher ratings scales were used to confirm a DSM-IV diagnosis. | Lifetime version of parent- rated Social Communication Questionnaire Autism Diagnostic Interview - Revised                          | Latent class analysis of Social Communication Questionnaire symptoms in probands with ADHD identified five clusters that corresponded with domains of the Autism Diagnostic Interview - Revised; three of the clusters with high mean Social Communi- cation Questionnaire scores were used to identify autistic traits: • Cluster 2: repetitive and stereotyped behaviors (mean score, 10.22) /square4 Cluster 4: communication and social reciprocal interaction (mean score, 13.58) /square4 Cluster 5: repetitive and stereotyped behaviors; communica- tion, and social reciprocal interaction (mean score, 21.4) |

ADHD, Attention-deficit/hyperactivity disorder; DSM-IV, Diagnostic and Statistical Manual of  Mental Disorders, 4th Edition; DSM-IV-TR, Diagnostic and Statistical Manual of  Mental Disorders, 4th Edition, Text Revision Figure 1. Prevalence of Autistic Traits in ADHD Children Reported in Reviewed Studies A. Grzadinski 2011: Prevalence of Autistic Traits in ADHD Children

50%

40%

30%

20%

10%

0%

20%

n=16

B. Kochhar 2011: Prevalence of Autistic Traits in

ADHD children

80%

60% -

40%

27%

n=8

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Figure  1  shows  the  prevalence  of   autistic  traits among ADHD probands as reported in each of the three studies  reviewed.  All studies showed  a  sizeable prevalence of  autistic traits, which ranged from 7% to 60% among children with ADHD.

## Detailed Review of Identified Studies

Study by Grzadzinski and Colleagues (2011)

The  sample  studied  by  Grzadzinski  and  colleagues included  75  children  who  met  the  diagnostic  criteria for  ADHD  and  69  healthy  controls.  Subjects  with history of  ASD were excluded. The first method that the authors used to identify autistic traits was the total T  score  of   at  least  60  (i.e.,  one  standard  deviation above  the  mean)  on  the  SRS.  The  SRS  is  a  65-item scale with 53 items that focus on socialcommunicative  abilities  and  12  items  that  probe  for repetitive  behaviors  or  restricted  patterns  of   interest (11).  An  SRS  cutoff   score  of   75  has  been  used  to differentiation  between  children  with  and  without ASD,  and  SRS  scores  have  been  shown  to  strongly correlate  with  the  Autistic  Diagnostic  Interview ,  Revised (8;11;12). This approach yielded a prevalence of autistic traits among children with ADHD of  32% (N = 25) (see Figure 1, A ). Similar results were obtained with the use of  the Children's Communication Checklist-2  (CCC-2).  The  CCC-2  is  a  checklist  that addresses 10 communication-related domains: 1) speech; 2) syntax; 3) semantics; 4) coherence; 5) inappropriate initiation; 6) stereotyped language; 7) use of context; 8) non-verbal communication; 9) social relations; and 10) interests. The General Communication Composite score for the CCC-2 represents the sum of  the  scores  of   the  first  seven  listed  domains,  and the Social Interaction  Deviance Composite  score represents the sum of the scores of  domains 5, 8, 9, and 10 subtracted from the sum of the total of the scores  of   the  remaining  domains.  Reports  suggest that  a  General  Communication  Composite  score  of less  than  55  in  combination  with  a  negative  Social

32%

п=24

35%

n=25

60%

n=18

Interaction  Deviance  Composite  score  or  a  Social Interaction Deviance Composite score of -15 or less correlate with a profile that includes ASD (13;14).

In  this  study,  the  authors  used  the  previously  described  CCC-2  cutoff  scores  that  identify  ASD profiles to detect children with ADHD who also have autistic  traits  and  found  that  35%  of   these  children demonstrated such traits. When the authors combined the SRS and the CCC-2 definitions of autistic traits, they  found  that  20%  of   children  with  ADHD  were identified as having such traits (see Figure 1, A ). Irrespective  of   the  method  used,  children  with  ADHD with  autistic traits  showed  statistically  significantly more deviant scores for each domain of the SRS: 1) social; 2) communication; and 3) restricted/repetitive behavior/interests. This was true even after accounting for the severity of  the child's psychopathology and ADHD symptoms.  Children  with  ADHD  with  and without  autistic  traits  did  not  differ  with  regard  to their symptomatology related to inattention, hyperactivity,  anxiety,  or  intelligence.  Children  with  ADHD with  the  autistic  trait  profile  also  had  significantly higher  ratings  of   oppositional  behavior  according  to the  Conners'  Parent  Rating  Scale  -  Revised:  Long Version  (15)  and  more  significantly  impaired  scores on the withdrawn/depressed and total problems domains of the Child Behavior Checklist (16).

## Study by Kochhar and Colleagues (2011)

Kochhar and colleagues' (10) sample consisted of  30 children  with  ADHD  and  30  healthy  controls,  both without ASD diagnoses. The authors used the Social Aptitudes Scale (17), a  10-item scale that forms part of the Development and Well-Being Assessment. For this assessment, parents were asked to compare their child's  behaviors  with  those  of   their  peers  across  a range  of   situations.  Autistic  traits  were  defined  by  a score  of   12  or  less  on  the  Social  Aptitudes  Scale, which has been reported to be indicative of  difficulties with social functioning (18). Sixty percent of  the children with ADHD in this sample met this criterion for  autistic  traits  as  compared  with  none  of   control group ( P < .05) (see Figure 1, B ).

The second measure that the authors used was the Lifetime version of  the Social Communication Questionnaire (SCQ) (19). This is a well-validated, 40-item, parent-rated questionnaire for autism screening among  children.  Reports  recommend  using  an  SCQ cutoff   score  of   15  to  separate  children  with  ASD from those without ASD. In this study, a significantly higher  rate  of   autistic  traits  (27%  for  children  with ADHD vs. 0% for controls; P <  .05)  was  identified with the use of  this score (Figure 1, B ). As compared with  children  without  autistic  traits,  children  with ADHD with the autistic trait profile had significantly higher  levels  of   communication  and  social  deficits; however, they did not demonstrate repetitive or stereotyped behaviors, even after controlling for intelligence.  Children  with  ADHD  with  autistic  traits demonstrated  significant  differences  in  6  of   the  16 items  of   the  social  domain  of   the  SCQ:  1)  friendly chat; 2) eye gaze; 3) offering to share; 4) response to another  child's  approaches;  5)  imaginative  play  with peers; and 6) group play. These children also had significant differences in 5 of  the 13 items of  the communication domain of this assessment: 1) stereotyped utterances;  2)  inappropriate  questions;  3)  verbal  rituals; 4) imitation deficit; and 5) imaginative play deficit.

## Study by Mulligan and Colleagues (2009)

The study by Mulligan and colleagues (4) looked at a sample  that  consisted  of   821  children  with  ADHD and 149 healthy controls. Subjects with an ASD diagnosis  were  excluded.  This  study  also  defined  autistic traits  using  the  Lifetime  version  of   the  SCQ,  but  a latent class analysis was also run on its 39 questions to determine if  responses to the questionnaire identified one  or  more  clusters  of   children  within  the  ADHD group. The cluster analysis identified five clusters that corresponded  with  the  following  domains  of   the Autism Diagnostic Interview  - Revised  (12): Cluster 1: few or no symptoms of autism; Cluster 2: repetitive and stereotyped behaviors; Cluster 3: communication; Cluster 4: communication and social reciprocal interaction; and Cluster 5: all three domains. The authors measured  the  mean  SCQ  score  for  each  cluster  and then  examined  the  size  of   the  ADHD  probands  of the  five  clusters.  The  mean  SCQ  scores  of   ADHD probands  in  the  clusters  were  as  follows:  Cluster  1: 2.24; Cluster 2: 10.22; Cluster 3: 7.04; Cluster 4: 13.58; and Cluster 5: 21.4. The mean SCQ score of healthy controls was 3.89. Cluster 1 consisted of  31% of  the ADHD  probands;  Cluster  2  consisted  of  22.5%, Cluster  3  consisted  of   21%,  Cluster  4  consisted  of 18.5%, and Cluster 5 consisted of  7%. Although the exact  prevalence  of   autistic  traits  in  this  sample  of children  with  ADHD  cannot  be  accurately  determined,  the  formation  of   these  clusters  suggested  a prevalence range of  7% (Cluster 5), as defined by the strictest criteria, to 48%, as defined by looser criteria (i.e.,  the  sum  of   Clusters  2,  4,  and  5  when  the  SCQ scores were higher than the mean) (see Figure 1, C ). Subjects  in  Cluster  5  were  also  more  likely  to  have oppositional defiant disorder (ODD) (77%), conduct disorder (44%), and language disorder (25%).

## Discussion

Our systematic review of the extant literature examined the prevalence and correlates of autistic traits in children with a clinical diagnosis of  ADHD in whom a  diagnosis  of   ASD  had  been  explicitly  excluded. Only  three  studies  met  our  inclusion  and  exclusion criteria.  The  three  studies  encompassed  926  children with  ADHD  and  reported  a  prevalence  of   autistic traits in the samples studied that ranged from 7% to 60%. In all three  studies,  children with ADHD who were  afflicted  with  autistic  traits  had  more  severe illness and more dysfunction, particularly in the interpersonal domain.

Despite the varied assessment methods used to define  autistic  traits,  all  three  studies  identified  a  substantial prevalence of  these traits among children with ADHD. This finding is  particularly  noteworthy  considering  that  the  investigators  explicitly  ruled  out  a diagnosis  of   ASDs.  Taken  together,  these  findings highlight that autistic traits  are common among children with ADHD.

It is noteworthy that all three studies identified social and communication deficits associated with autistic traits in children with ADHD, even after controlling for the severity of  the ADHD symptoms, intelligence, and other measures of psychopathology. Grzadzinski  and  colleagues  (9)  showed  that  children with  ADHD  with  autistic  traits  had  elevated  scores for all SRS items, including items in the social, communication, repetitive, and restrictive behavior categories  as  well  as  the  category  of   items  that  were  not specific to ASDs. Similar findings of  heightened deficits in social and communication profiles among children  with  ADHD  with  autistic  traits  were  also  reported by Kochhar and colleagues (10). It is of  note that  these  authors  failed  to  find  other  features  of autism  such  as  repetitive  and  stereotyped  deficits, which suggests that autistic traits selectively identify a particular  type of  social  and  communication deficits. Taken  together,  these  findings  strongly  suggest  that the  social  and  communication  impairments  in  this sample of children with ADHD were not solely the results of  the core symptoms of ADHD. Appropriate consideration  of   these  different  types  of   social  and communication deficits in  children  with  ADHD  can improve efforts that are designed to help individualize therapeutic  approaches  to  address  such  deficits  in these patients.

Grzadzinski  and  colleagues  (9)  and  Mulligan  and colleagues (4) also reported that children with ADHD with autistic traits had higher levels of  disruptive behavior disorders in general and of  ODD in particular. These findings are consistent with the higher rates of disruptive  behavior  disorders  identified  in  children with ASDs and comorbid ADHD as compared with children with ASDs without comorbid  ADHD (20;21).

The finding of elevated rates of  ODD among children with ADHD with autistic traits is also consistent with  reports  of   increased  social  difficulties  among children  with  ADHD  and  comorbid  ODD  (22;23). This is  also  consistent  with  the  findings  reported  by Lundstrom  and  colleagues  (6),  who  found  that  the presence  of   even  low-grade  autistic  traits  increased the  risk  of   ADHD,  conduct  disorder,  anxiety,  and substance  abuse  among  patient  samples  who  were enrolled  in  nationwide  epidemiological  twin  studies. Clearly  more  work  is  needed  to  further  understand the  three-way  associations  among  ADHD, disruptive behavior  disorders,  and  autistic  traits.  If   some  cases of ODD among youth with ADHD are mediated by the  presence  of   ASD  symptoms,  this  would  likely have implications for treatment choices.

Although the reasons for the high prevalence of  autistic  traits  among  children  with  ADHD  are  not  entirely  clear, one explanation for their presence is that of shared genetic susceptibility between ADHD and ASDs.  As  mentioned  previously,  twin,  family,  and linkage  studies  have  indicated  that  the  two  disorders share  a  portion  of   their  heritable  etiology  (1-6;24). Smalley and colleagues (24) mapped the genetic linkage  of   ADHD  to  a  7-Mb  region  on  chromosome 16p13  that  had  previously  been  highlighted  in  three genome  scans  for  autism,  thereby  suggesting  that variations  in  chromosome  16p13  may  contribute  to the  common  deficits  found  with  both  ADHD  and autism. Similarly, the excessive frequency of  large, rare copy  number  variations  in  chromosome  16p13  was reported  for  a  well-characterized  sample  of   patients with  ADHD  (25),  and  significantly  enriched  copy number  variants  for  certain  loci  were  implicated  for autism  in  patients  with  ADHD  (7).  In  a  study  by Lionel and colleagues (26), deletions of  the neuronal ASTN2 gene and the ASTN2-intronic TRIM32 gene yielded  the  strongest  associations  with  ADHD  and ASD; this was in addition to deletions in other shared candidate genes, such as CHCHD3 and MACROD2, and  in  the  16p11.2  region.  More  work  is  needed  to further investigate other etiological risk factors for the development  of  autistic  traits in individuals  with ADHD and to examine whether autistic traits  could represent  an  intermediate  phenotype  or  endophenotype  worthy  of   consideration  in  neurobiological  and genetic studies of  ADHD.

Our findings are tempered by some methodological shortcomings.  Although  when  considered  together the  studies  included  a  very  sizeable  number  of   children with ADHD (N = 926), because we were only able  to  identify  three  informative  studies  in  our  review,  our  conclusions  need  to  be  viewed  as  preliminary  until  they  are  confirmed  in  future  studies.  The studies  examined  excluded  children  who  had  been diagnosed with ASDs; however, these studies did not specifically state whether children who met the criteria for  pervasive  developmental  disorder,  not  otherwise specified  were  specifically  excluded.  Because  the  rating scales used in these studies were developed for the detection  of   ASDs,  it  is  possible  that  these  studies may  have  included  children  with  otherwise  undiagnosed and previously undetected subsyndromal forms of  ASDs  as  opposed  to  autistic  traits.  Because  the different  studies  used  different  methods  to  identify autistic traits, it remains uncertain whether the definitions used captured the same constructs. Because the three  studies  relied  on  clinically  ascertained  samples, we do not know whether these findings will be generalizable to community samples.

Despite these considerations, our review of  the literature  indicates  that  a  substantial  minority  of   children with ADHD manifests autistic traits. Our review also indicates that the presence  of  autistic traits among  children  with  ADHD  heralds  a  more  compromised social and communication environment for such children and that these traits are reminiscent of the  social  and  communication  impairments  seen  in children  with  ASDs.  More  work  is  needed  to  gain additional insights regarding the clinical and neurobiological  implications  of   autistic  traits  in  children  with ADHD.

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## Authors' Disclosures

Dr. Joseph Biederman is currently receiving research support from the following sources: APSARD, The Department of Defense, ElMindA, Janssen, McNeil, Shire, and  VayaPharma/Enzymotec. In  2013,  Dr.  Joseph  Biederman received  an honorarium  from  the  MGH  Psychiatry  Academy  for  a  tuition-funded CME course. He has a US Patent Application pending (Provisional Number  #61/233,686)  through  MGH  corporate  licensing,  on  a  method  to prevent  stimulant  abuse.  Dr.  Biederman  received  departmental  royalties from a copyrighted rating scale used for ADHD diagnoses, paid by Shire and Sunovion; these royalties are paid to the Department of  Psychiatry at MGH. In  2012,  Dr.  Joseph  Biederman received  an  honorarium  from  the MGH  Psychiatry  Academy  and  The  Children's  Hospital  of   Southwest Florida/Lee Memorial Health System for tuition-funded CME courses. In 2011, Dr. Joseph Biederman gave a single unpaid talk for Juste Pharmaceutical  Spain,  received  honoraria  from  the  MGH  Psychiatry  Academy  for  a tuition-funded  CME  course,  and  received  honoraria  for  presenting  at international scientific conference on ADHD. He also received an honorarium  from  Cambridge  University  Press  for  a  chapter  publication.  Dr. Biederman  received  departmental  royalties  from  a  copyrighted  rating scale used  for  ADHD  diagnoses,  paid  by  Eli  Lilly,  Shire  and  AstraZeneca; these  royalties are  paid  to  the  Department  of  Psychiatry  at MGH. In 2010, Dr. Joseph Biederman received a speaker's fee from a single talk given at Fundación Dr.Manuel Camelo A.C. in Monterrey Mexico. Dr. Biederman  provided  single  consultations  for  Shionogi  Pharma  Inc.  and Cipher  Pharmaceuticals  Inc.;  the  honoraria  for  these  consultations  were paid  to  the  Department  of   Psychiatry  at  the  MGH.  Dr.  Biederman  received honoraria from the MGH Psychiatry Academy for a tuition-funded CME course. In  previous  years,  Dr.  Joseph  Biederman received research  support, consultation fees, or speaker's fees for/from the following additional sources:    Abbott,  Alza,  AstraZeneca,  Boston  University,  Bristol  Myers Squibb,  Celltech,  Cephalon,  Eli  Lilly  and  Co.,  Esai,  FundacionAreces (Spain), Forest, Glaxo, Gliatech, Hastings Center, Janssen, McNeil, Medice Pharmaceuticals  (Germany),  Merck,  MMC  Pediatric,  NARSAD,  NIDA, New  River,  NICHD,  NIMH,  Novartis,  Noven,  Neurosearch,  Organon, Otsuka,  Pfizer,  Pharmacia,  Phase  V  Communications,  Physicians  Academy,  The  Prechter  Foundation,  Quantia  Communications,  Reed  Exhibitions, Shire, the Spanish Child Psychiatry Association, The Stanley Foundation, UCB Pharma Inc., Veritas, and Wyeth.

Gagan  Joshi,  M.D.  receives  research  support  from  Forest  Research Laboratories and Duke University as a site principal investigator for multisite  clinical  trials.  He  is  a  co-investigator  for  clinical  trials  sponsored  by Schering-Plough Corporation, Shire, Elminda, and the US Department of Defense. In 2011, Dr. Joshi received research support from Shire, Johnson &  Johnson  Pharmaceutical  Research  and  Development,  Eli  Lilly,  Forest Research Laboratories, Schering-Plough Corporation, ElMinda, and NIMH. In previous years, Dr. Joshi  received research support from  the following sources: Ethel DuPont Warren Fellowship Award 2005-6 ; Pilot Research  Award from  the  American  Academy  of   Child  and  Adolescent Psychiatry  2005 ; National  Institute  of   Mental  Health  (Reviewer  and member of the NIMH Editorial Board) ; McNeil Pediatrics (CME sponsored  by SynerMed Communications) ; Bristol  Myers Squibb  (Site PI  for Multi-centered Trial) ; Glaxo Smith Kline (Site PI for Multi-centered Trial) ; Shire  (Member  of   national  advisory  board) ; Subinvestigator  for  clinical trials  sponsored  by  Shire,  Johnson  &  Johnson,  Pfizer,  Merck,  Cephlon, McNeil,  Eli-Lily, Abbott, Novartis, Bristol Myers  Squibb,  Organon, Otsuka, Takeda, & New River Pharmaceuticals.

In  the  past  year,  Dr.  Faraone  received  consulting  income  and/or  research support from Shire, Otsuka and Alcobra and research support from the National Institutes of  Health (NIH).  He is also on the Clinical Advisory  Board  for  Akili  Interactive  Labs.    In  previous  years,  he  received consulting fees or was on Advisory Boards or participated in continuing medical education programs sponsored by: Shire, McNeil, Janssen, Novartis,  Pfizer  and  Eli  Lilly.  Dr.  Faraone  receives  royalties  from  books  published by Guilford Press: Straight Talk about Y our Child's Mental Health and Oxford University Press: Schizophrenia: The Facts .

Mai  Uchida,  M.D.,  Andrea  Spencer,  M.D.,  Tara  Kenworthy  and  K. Yvonne Woodworth have no financial disclosures.

## Acknowledgements

This was supported by the Pediatric Psychopharmacology Council Fund. Dr. Amelia Kotte drafted the previous version of  this manuscript.