Editing Attention deficit hyperactivity disorder (section)

==Signs and symptoms==
Inattention, hyperactivity (restlessness in adults), disruptive behaviour, and impulsivity are common in ADHD.<ref name=cdc2016facts/><ref name="National Institute of Mental Health_2023">{{Cite web |title=Attention-Deficit/Hyperactivity Disorder |url=https://www.nimh.nih.gov/health/topics/attention-deficit-hyperactivity-disorder-adhd |access-date=2 January 2024 |website=National Institute of Mental Health |date=September 2023 }}</ref><ref name="National Institute of Mental Health">{{Cite web |title=Attention-Deficit/Hyperactivity Disorder in Adults: What You Need to Know |url=https://www.nimh.nih.gov/health/publications/adhd-what-you-need-to-know |access-date=2 January 2024 |website=[[National Institute of Mental Health]]}}</ref> Academic difficulties are frequent, as are problems with relationships.<ref name="National Institute of Mental Health_2023" /><ref name="National Institute of Mental Health" /><ref name="ICSI2012">{{cite web |date=Mar 2012 |publisher=National Guideline Clearinghous |title=Diagnosis and management of attention deficit hyperactivity disorder in primary care for school-age children and adolescents |url=http://guidelines.gov/content.aspx?f=rss&id=36812 |archive-url=https://web.archive.org/web/20130301124247/http://guidelines.gov/content.aspx?f=rss&id=36812 |archive-date=1 March 2013 |access-date=10 October 2012 |page=79 |vauthors = Dobie C, Donald WB, Hanson M, Heim C, Huxsahl J, Karasov R, Kippes C, Neumann A, Spinner P, Staples T, Steiner L}}</ref> The signs and symptoms can be difficult to define, as it is hard to draw a line at where normal levels of inattention, hyperactivity, and impulsivity end and significant levels requiring interventions begin.<ref name ="Ramsay_2007">{{cite book |vauthors=Ramsay JR |title=Cognitive behavioral therapy for adult ADHD |publisher=Routledge |year=2007 |isbn=978-0-415-95501-0 |pages=4, 25–26}}</ref>

According to the [[DSM-5|fifth edition of the ''Diagnostic and Statistical Manual of Mental Disorders'']] (DSM-5) and its text revision ([[DSM-5-TR]]), symptoms must be present for six months or more to a degree that is much greater than others of the [[age appropriate|same age]].<ref name=DSM5/><ref name=DSM5TR/> This requires at least six symptoms of either inattention or hyperactivity/impulsivity for those under 17 and at least five symptoms for those 17 years or older.<ref name=DSM5/><ref name=DSM5TR/> The symptoms must be present in at least two settings (e.g., social, school, work, or home), and must directly interfere with or reduce quality of functioning.<ref name=DSM5/> Additionally, several symptoms must have been present before age 12 as per DSM-5 criteria.<ref name=DSM5TR/><ref name=DSM5/><ref>{{cite journal |vauthors=Epstein JN, Loren RE |title=Changes in the Definition of ADHD in DSM-5: Subtle but Important |journal=Neuropsychiatry |volume=3 |issue=5 |pages=455–458 |date=October 2013 |pmid=24644516 |pmc=3955126 |doi=10.2217/npy.13.59}}</ref> However, research indicates the age of onset should not be interpreted as a prerequisite for diagnosis given contextual exceptions.<ref name="Faraone_2016" />

=== {{anchor|ADHD-PH}} Presentations ===
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ADHD is divided into three primary presentations:<ref name=DSM5TR/><ref name="Ramsay_2007" />
* [[Attention deficit hyperactivity disorder predominantly inattentive|predominantly inattentive]] (ADHD-PI or ADHD-I)
* predominantly hyperactive-impulsive (ADHD-PH or ADHD-HI)
* combined presentation (ADHD-C).

The table "Symptoms" lists the symptoms for ADHD-I and ADHD-HI from two major classification systems. Symptoms which can be better explained by another psychiatric or medical condition which an individual has are not considered to be a symptom of ADHD for that person. In DSM-5, subtypes were discarded and reclassified as presentations of the disorder that change over time.
{| class="wikitable"
|+Symptoms
!Presentations
!width=45%|{{abbr|DSM-5|Diagnostic and Statistical Manual, 5th Edition}} and {{abbr|DSM-5-TR|Diagnostic and Statistical Manual, 5th Edition, Text Revision}} symptoms<ref name=DSM5/><ref name=DSM5TR/>
!width=45%|{{abbr|ICD-11|International Classification of Diseases |edition=11th}} symptoms<ref name="ICD-11" />
|-
|Inattention
|<!-- DSM-5 -->Six or more of the following symptoms in children, and five or more in adults, excluding situations where these symptoms are better explained by another psychiatric or medical condition:
* Frequently overlooks details or makes careless mistakes
* Often has difficulty maintaining focus on one task or play activity
* Often appears not to be listening when spoken to, including when there is no obvious distraction
* Frequently does not finish following instructions, failing to complete tasks
* Often struggles to organise tasks and activities, to meet deadlines, and to keep belongings in order
* Is frequently reluctant to engage in tasks which require sustained attention
* Frequently loses items required for tasks and activities
* Is frequently easily distracted by extraneous stimuli, including thoughts in adults and older teenagers
* Often forgets daily activities, or is forgetful while completing them.
|<!-- ICD-11 -->Multiple symptoms of inattention that directly negatively impact occupational, academic or social functioning. Symptoms may not be present when engaged in highly stimulating tasks with frequent rewards. Symptoms are generally from the following clusters:
* Struggles to maintain focus on tasks that are not highly stimulating/rewarding or that require continuous effort; details are often missed, and careless mistakes are frequent in school and work tasks; tasks are often abruptly abandoned in favour of another before they are completed.
* Easily distracted (including by own thoughts); may not listen when spoken to; frequently appears to be lost in thought
* Often loses things; is forgetful and disorganised in daily activities.

The individual may also meet the criteria for hyperactivity-impulsivity, but the inattentive symptoms are predominant.
|-
|Hyperactivity-Impulsivity
|<!-- DSM-5 -->Six or more of the following symptoms in children, and five or more in adults, excluding situations where these symptoms are better explained by another psychiatric or medical condition:
* Is often fidgeting or squirming in seat
* Frequently has trouble sitting still during dinner, class, in meetings, etc.
* Frequently runs around or climbs in inappropriate situations. In adults and teenagers, this may be present only as restlessness.
* Often cannot quietly engage in leisure activities or play
* Frequently seems to be "on the go" or appears uncomfortable when not in motion
* Often talks excessively
* Often answers a question before it is finished, or finishes people's sentences
* Often struggles to wait their turn, including waiting in lines
* Frequently interrupts or intrudes, including into others' conversations or activities, or by using people's things without asking.
|<!-- ICD-11 -->Multiple symptoms of hyperactivity/impulsivity that directly negatively impact occupational, academic or social functioning. Typically, these tend to be most apparent in environments with structure or which require self-control. Symptoms are generally from the following clusters:
* Excessive motor activity; struggles to sit still, often leaving their seat; prefers to run about; in younger children, will fidget when attempting to sit still; in adolescents and adults, a sense of physical restlessness or discomfort with being quiet and still.
* Talks too much; struggles to quietly engage in activities.
* Blurts out answers or comments; struggles to wait their turn in conversation, games, or activities; will interrupt or intrude on conversations or games.
* A lack of forethought or consideration of consequences when making decisions or taking action, instead tending to act immediately (e.g., physically dangerous behaviours including reckless driving; impulsive decisions).

The individual may also meet the criteria for inattention, but the hyperactive-impulsive symptoms are predominant.
|-
|Combined
|<!-- DSM-5 -->Meet the criteria for both inattentive and hyperactive-impulsive ADHD.
|<!-- ICD-11 -->Criteria are met for both inattentive and hyperactive-impulsive ADHD, with neither clearly predominating.
|}

Girls and women with ADHD tend to display fewer hyperactivity and impulsivity symptoms but more symptoms of inattention and distractibility.<ref>{{cite journal |vauthors=Gershon J |title=A meta-analytic review of gender differences in ADHD |journal=[[Journal of Attention Disorders]] |volume=5 |issue=3 |pages=143–154 |date=January 2002 |pmid=11911007 |doi=10.1177/108705470200500302 |s2cid=8076914}}</ref>

Symptoms are expressed differently and more subtly as the individual ages.<ref name="Kooij_2010">{{cite journal |vauthors=Kooij SJ, Bejerot S, Blackwell A, Caci H, Casas-Brugué M, Carpentier PJ, Edvinsson D, Fayyad J, Foeken K, Fitzgerald M, Gaillac V, Ginsberg Y, Henry C, Krause J, Lensing MB, Manor I, Niederhofer H, Nunes-Filipe C, Ohlmeier MD, Oswald P, Pallanti S, Pehlivanidis A, Ramos-Quiroga JA, Rastam M, Ryffel-Rawak D, Stes S, Asherson P |title=European consensus statement on diagnosis and treatment of adult ADHD: The European Network Adult ADHD |journal=[[BMC Psychiatry]] |volume=10 |issue=67 |page=67 |date=September 2010 |pmid=20815868 |pmc=2942810 |doi=10.1186/1471-244X-10-67 |doi-access=free}}</ref>{{rp|6|quote=Whereas the core symptoms of hyperactivity, impulsivity and inattention, are well characterised in children, these symptoms may have different and more subtle expressions in adult life.}} Hyperactivity tends to become less overt with age and turns into inner restlessness, difficulty relaxing or remaining still, talkativeness or constant mental activity in teens and adults with ADHD.<ref name="Kooij_2010"/>{{rp|pp=6–7 |quote=For instance, where children with ADHD may run and climb excessively, or have difficulty in playing or engaging quietly in leisure activities, adults with ADHD are more likely to experience inner restlessness, inability to relax, or over talkativeness. Hyperactivity may also be expressed as excessive fidgeting, the inability to sit still for long in situations when sitting is expected (at the table, in the movie, in church or at symposia), or being on the go all the time. ... For example, physical overactivity in children could be replaced in adulthood by constant mental activity, feelings of restlessness and difficulty engaging in sedentary activities.}} Impulsivity in adulthood may appear as thoughtless behaviour, impatience, irresponsible spending and sensation-seeking behaviours,<ref name="Kooij_2010"/>{{rp|6|quote=Impulsivity may be expressed as impatience, acting without thinking, spending impulsively, starting new jobs and relationships on impulse, and sensation seeking behaviours.}} while inattention may appear as becoming easily bored, difficulty with organisation, remaining on task and making decisions, and sensitivity to stress.<ref name="Kooij_2010"/>{{rp|6|quote=Inattention often presents as distractibility, disorganization, being late, being bored, need for variation, difficulty making decisions, lack of overview, and sensitivity to stress.}}

====Characteristics in childhood====
Difficulties managing anger are more common in children with ADHD,<ref>{{cite web |title=ADHD Anger Management Directory |publisher=Webmd.com |url=http://www.webmd.com/add-adhd/adhd-anger-management-directory |access-date=17 January 2014 |url-status=live |archive-date=5 November 2013 |archive-url=https://web.archive.org/web/20131105032151/http://www.webmd.com/add-adhd/adhd-anger-management-directory}}</ref> as are delays in [[communication disorder|speech, language]] and motor development.<ref name="ICD10"/><ref name="pmid22201208">{{cite journal |vauthors=Bellani M, Moretti A, Perlini C, Brambilla P |title=Language disturbances in ADHD |journal=Epidemiology and Psychiatric Sciences |volume=20 |issue=4 |pages=311–315 |date=December 2011 |pmid=22201208 |doi=10.1017/S2045796011000527 |doi-access=free}}</ref> Poorer [[handwriting]] is more common in children with ADHD.<ref name="Racine_2008">{{cite journal |vauthors=Racine MB, Majnemer A, Shevell M, Snider L |title=Handwriting performance in children with attention deficit hyperactivity disorder (ADHD) |journal=[[Journal of Child Neurology]] |volume=23 |issue=4 |pages=399–406 |date=April 2008 |pmid=18401033 |doi=10.1177/0883073807309244 |s2cid=206546871}}</ref> Poor handwriting can be a symptom of ADHD in itself due to decreased attentiveness. When this is a pervasive problem, it may also be attributable to [[dyslexic|dyslexia]]<ref>{{cite journal |vauthors=Peterson RL, Pennington BF |title=Developmental dyslexia |journal=[[The Lancet]] |volume=379 |issue=9830 |pages=1997–2007 |date=May 2012 |pmid=22513218 |pmc=3465717 |doi=10.1016/S0140-6736(12)60198-6}}</ref><ref>{{cite journal |vauthors=Sexton CC, Gelhorn HL, Bell JA, Classi PM |title=The co-occurrence of reading disorder and ADHD: epidemiology, treatment, psychosocial impact, and economic burden |journal=[[Journal of Learning Disabilities]] |volume=45 |issue=6 |pages=538–564 |date=November 2012 |pmid=21757683 |doi=10.1177/0022219411407772 |s2cid=385238}}</ref> or [[dysgraphia]]. There is significant overlap in the symptomatologies of ADHD, dyslexia, and dysgraphia,<ref name="Nicolson_2011">{{cite journal |vauthors=Nicolson RI, Fawcett AJ |title=Dyslexia, dysgraphia, procedural learning and the cerebellum |journal=Cortex; A Journal Devoted to the Study of the Nervous System and Behavior |volume=47 |issue=1 |pages=117–127 |date=January 2011 |pmid=19818437 |doi=10.1016/j.cortex.2009.08.016 |s2cid=32228208}}</ref> and 3 in 10 people diagnosed with dyslexia experience co-occurring ADHD.<ref>{{cite web |url=https://www.webmd.com/add-adhd/adhd-dyslexia-tell-apart |title=Dyslexia and ADHD |access-date=19 May 2022 |archive-date=21 February 2023 |archive-url=https://web.archive.org/web/20230221112159/https://www.webmd.com/add-adhd/adhd-dyslexia-tell-apart |url-status=live}}</ref> Although it causes significant difficulty, many children with ADHD have an attention span equal to or greater than that of other children for tasks and subjects they find interesting.<ref name="Walitza_2012">{{cite journal |vauthors=Walitza S, Drechsler R, Ball J |title= [The school child with ADHD] |language=de |journal=Therapeutische Umschau |volume=69 |issue=8 |pages=467–473 |date=August 2012 |pmid=22851461 |doi=10.1024/0040-5930/a000316 |trans-title=The school child with ADHD}}</ref>

===Emotional dysregulation===
Although not listed as an official symptom, [[emotional dysregulation]] or [[mood lability]] is generally understood to be a common symptom of ADHD.<ref name="Retz_2012">{{cite journal |vauthors=Retz W, Stieglitz RD, Corbisiero S, Retz-Junginger P, Rösler M |title=Emotional dysregulation in adult ADHD: What is the empirical evidence? |journal=Expert Review of Neurotherapeutics |volume=12 |issue=10 |pages=1241–1251 |date=October 2012 |pmid=23082740 |doi=10.1586/ern.12.109 |s2cid=207221320}}</ref><ref>{{cite journal |vauthors=Faraone SV, Rostain AL, Blader J, Busch B, Childress AC, Connor DF, Newcorn JH |title=Practitioner Review: Emotional dysregulation in attention-deficit/hyperactivity disorder - implications for clinical recognition and intervention |journal=[[Journal of Child Psychology and Psychiatry|Journal of Child Psychology and Psychiatry, and Allied Disciplines]] |volume=60 |issue=2 |pages=133–150 |date=February 2019 |pmid=29624671 |doi=10.1111/jcpp.12899}}</ref><ref>{{cite journal |vauthors=Shaw P, Stringaris A, Nigg J, Leibenluft E |title=Emotion dysregulation in attention deficit hyperactivity disorder |journal=[[The American Journal of Psychiatry]] |volume=171 |issue=3 |pages=276–293 |date=March 2014 |pmid=24480998 |pmc=4282137 |doi=10.1176/appi.ajp.2013.13070966}}</ref><ref name="Kooij_2010"/>{{rp|6|quote=In addition, many adults with ADHD experience lifetime mood lability with frequent highs and lows, and short-fuse temper outburst.}}

===Relationship difficulties===
People with ADHD of all ages are more likely to have problems with [[social skills]], such as social interaction and forming and maintaining friendships.<ref>{{cite journal |vauthors=Carpenter Rich E, Loo SK, Yang M, Dang J, Smalley SL |title=Social functioning difficulties in ADHD: association with PDD risk |journal=[[Clinical Child Psychology and Psychiatry]] |volume=14 |issue=3 |pages=329–344 |date=July 2009 |pmid=19515751 |pmc=2827258 |doi=10.1177/1359104508100890}}</ref> This is true for all presentations. About half of children and adolescents with ADHD experience [[social rejection]] by their peers compared to 10–15% of non-ADHD children and adolescents. People with attention deficits are prone to having difficulty processing verbal and nonverbal language which can negatively affect social interaction. They may also drift off during conversations, miss social cues, and have trouble learning social skills.<ref>{{cite journal |vauthors=Coleman WL |title=Social competence and friendship formation in adolescents with attention-deficit/hyperactivity disorder |journal=Adolescent Medicine |volume=19 |issue=2 |pages=278–99, x |date=August 2008 |pmid=18822833}}</ref>

===Hyperfocus===
An association between ADHD and hyperfocus, a state characterised by intense and narrow concentration on a specific stimulus, object or task for a prolonged period of time,<ref name="Chutko_et_al_2024">{{cite journal |last1=Chutko |first1=L. S. |last2=Surushkina |first2=S. Yu. |last3=Yakovenko |first3=E. A. |last4=Cherednichenko |first4=D. V. |title=Attention Deficit Hyperactivity Disorder in Adults |journal=Neuroscience and Behavioral Physiology |date=June 2024 |volume=54 |issue=5 |pages=644–649 |doi=10.1007/s11055-024-01643-5}}</ref> has been widely reported in the [[Popular science|popular science press]] and media.<ref name="Groen_et_al_2020" >{{cite journal |last1=Groen |first1=Yvonne |last2=Priegnitz |first2=Ulrike |last3=Fuermaier |first3=Anselm B. M. |last4=Tucha |first4=Lara |last5=Tucha |first5=Oliver |last6=Aschenbrenner |first6=Steffen |last7=Weisbrod |first7=Matthias |last8=Garcia Pimenta |first8=Miguel |title=Testing the relation between ADHD and hyperfocus experiences |journal=Research in Developmental Disabilities |date=1 December 2020 |volume=107 |issue=103789 |doi=10.1016/j.ridd.2020.103789 |doi-access = free |pmid=33126147 |issn=0891-4222}}</ref> The phenomenon generally occurs when an individual is engaged in activities they find highly interesting, or which provide instant gratification, such as video games or online chatting.<ref name="epa_consensus_2019" /> Hyperfocus is not a recognised symptom of ADHD in diagnostic manuals, but is frequently referred to as a symptom of ADHD in academic literature<ref name="Ashinoff_Abu_Akel_2019">{{cite journal |vauthors=Ashinoff BK, Abu-Akel A |date=February 2021 |title=Hyperfocus: the forgotten frontier of attention |journal=Psychological Research |volume=85 |issue=1 |pages=1–19 |doi=10.1007/s00426-019-01245-8 |pmc=7851038 |pmid=31541305}}</ref> and commonly reported in patients with ADHD in clinical practice.<ref name="Groen_et_al_2020" /> There is a lack of research into hyperfocus in ADHD.<ref name="Ashinoff_Abu_Akel_2019" /> Studies in 2016, 2019 and 2024 found that individuals with ADHD diagnoses or self-reported ADHD symptoms experience hyperfocus more often,<ref>{{cite journal |last1=Ozel-Kizil |first1=Erguvan Tugba |last2=Kokurcan |first2=Ahmet |last3=Aksoy |first3=Umut Mert |last4=Kanat |first4=Bilgen Bicer |last5=Sakarya |first5=Direnc |last6=Bastug |first6=Gulbahar |last7=Colak |first7=Burcin |last8=Altunoz |first8=Umut |last9=Kirici |first9=Sevinc |last10=Demirbas |first10=Hatice |last11=Oncu |first11=Bedriye |title=Hyperfocusing as a dimension of adult attention deficit hyperactivity disorder |journal=Research in Developmental Disabilities |date=1 December 2016 |volume=59 |pages=351–358 |doi=10.1016/j.ridd.2016.09.016|pmid=27681531 }}</ref><ref>{{cite journal |last1=Hupfeld |first1=Kathleen E. |last2=Abagis |first2=Tessa R. |last3=Shah |first3=Priti |title=Living "in the zone": hyperfocus in adult ADHD |journal=ADHD Attention Deficit and Hyperactivity Disorders |date=June 2019 |volume=11 |issue=2 |pages=191–208 |doi=10.1007/s12402-018-0272-y|pmid=30267329 }}</ref> or more acutely.<ref name="Glassey_Smilek_2024">{{cite journal |last1=Ayers-Glassey |first1=Samantha |last2=Smilek |first2=Daniel |title=The relations between hyperfocus and similar attentional states, adult ADHD symptoms, and affective dysfunction |journal=Current Psychology |date=March 2024 |volume=43 |issue=12 |pages=11254–11266 |doi=10.1007/s12144-023-05235-3}}</ref> A 2020 study did not find a higher frequency of hyperfocus in adults with ADHD, although it reported a positive correlation with self-reported ADHD traits. The discrepancy with other studies may reflect varying definitions and conceptions of hyperfocus.<ref name="Groen_et_al_2020"/>

A state of hyperfocus has been hypothesised as being beneficial, allowing individuals to focus on tasks for much longer than is typical.<ref name="Ashinoff_Abu_Akel_2019" /> Conversely, it can be difficult to disengage from and shift attention to other stimuli or tasks, leading to excessively prolonged attention.<ref name="Chutko_et_al_2024"/> It is related to risks such as internet addiction (see {{section link||Problematic digital media use}})<ref name="Ishii_et_al_2023" /> and to some types of offending behaviour.<ref>{{Cite journal |vauthors=Worthington R, Wheeler S |date=January 2023 |title=Hyperfocus and offending behaviour: a systematic review |journal=The Journal of Forensic Practice |volume=25 |issue=3 |pages=185–200 |doi=10.1108/JFP-01-2022-0005 |issn=2050-8794 |s2cid=258330884 |url=https://clok.uclan.ac.uk/46646/1/Manuscript%20with%20author%20details%2012.01.21.pdf}}</ref> Recent research has linked hyperfocus to the psychological concepts of [[Flow (psychology)|flow]], an enjoyable experience of deep engagement in an activity, and [[perseveration]], difficulty disengaging or switching from an activity.<ref name="Glassey_Smilek_2024"/>

===IQ test performance===
Certain studies have found that people with ADHD tend to have lower scores on [[intelligence quotient]] (IQ) tests.<ref name="Frazier_2004">{{cite journal |vauthors=Frazier TW, Demaree HA, Youngstrom EA |title=Meta-analysis of intellectual and neuropsychological test performance in attention-deficit/hyperactivity disorder |journal=[[Neuropsychology (journal)|Neuropsychology]] |volume=18 |issue=3 |pages=543–555 |date=July 2004 |pmid=15291732 |doi=10.1037/0894-4105.18.3.543 |s2cid=17628705}}</ref> The significance of this is controversial due to the differences between people with ADHD and the difficulty determining the influence of symptoms, such as distractibility, on lower scores rather than intellectual capacity. In studies of ADHD, higher IQs may be over-represented because many studies exclude individuals who have lower IQs despite those with ADHD scoring on average nine points lower on standardised intelligence measures.<ref name="Mackenzie_2016">{{cite journal |vauthors=Mackenzie GB, Wonders E |title=Rethinking Intelligence Quotient Exclusion Criteria Practices in the Study of Attention Deficit Hyperactivity Disorder |journal=[[Frontiers in Psychology]] |volume=7 |page=794 |date=2016 |pmid=27303350 |pmc=4886698 |doi=10.3389/fpsyg.2016.00794 |doi-access=free}}</ref> However, other studies contradict this, saying that in individuals with high intelligence, there is an increased risk of a missed ADHD diagnosis, possibly because of compensatory strategies in said individuals.<ref>{{cite journal |vauthors=Rommelse N, van der Kruijs M, Damhuis J, Hoek I, Smeets S, Antshel KM, Hoogeveen L, Faraone SV |title=An evidenced-based perspective on the validity of attention-deficit/hyperactivity disorder in the context of high intelligence |journal=[[Neuroscience & Biobehavioral Reviews]] |volume=71 |pages=21–47 |date=December 2016 |pmid=27590827 |doi=10.1016/j.neubiorev.2016.08.032 |hdl-access=free |s2cid=6698847 |hdl=2066/163023}}</ref>

Studies of adults suggest that negative differences in intelligence are not meaningful and may be explained by associated health problems.<ref>{{cite journal |vauthors=Bridgett DJ, Walker ME |title=Intellectual functioning in adults with ADHD: a meta-analytic examination of full scale IQ differences between adults with and without ADHD |journal=Psychological Assessment |volume=18 |issue=1 |pages=1–14 |date=March 2006 |pmid=16594807 |doi=10.1037/1040-3590.18.1.1}}</ref>