3.1.4 Differential Diagnosis
Attention-Deficit/Hyperactivity Disorder (ADHD),
which is characterized by symptoms of inattention, hyperactivity, and
impulsivity that are inconsistent with developmental level and that
negatively impact social and academic/occupational activities, must
be differentiated from . . .
In contrast to Attention-Deficit/Hyperactivity
Disorder . . .
Normative behaviors in active children
Are consistent with developmental level.
Lead to inattention that is related to
Oppositional Defiant Disorder
May be characterized by resistance to work
or school tasks because of a refusal to submit to others’ demands,
which is accompanied by negativity, hostility, and defiance. In
ADHD, however, the aversion to school or mentally demanding tasks
is due to difficulty in sustaining mental effort, forgetting instructions,
Intermittent Explosive Disorder
Is also characterized by high levels
of impulsive behavior, but unlike ADHD, there are episodes of serious
aggression toward others. An additional diagnosis of Intermittent
Explosive Disorder can be made if the recurrent impulsive aggressive
outbursts are in excess of those usually seen in ADHD and warrant independent
May be characterized by high levels of
impulsivity, but there is also a pattern of antisocial behavior.
Stereotypic Movement Disorder
Is characterized by repetitive motor
behavior that may resemble the increased motor behavior in ADHD.
In contrast to ADHD, however, the motor behavior is generally fixed
and repetitive (e.g., body rocking, self-biting), whereas the fidgetiness
and restlessness in ADHD are typically generalized.
Specific Learning Disorder
May be characterized by inattentive behavior
because of frustration, lack of interest, or limited ability. However, inattention
in individuals with Specific Learning Disorder who do not have ADHD
is not impairing outside of schoolwork.
Intellectual Disability (Intellectual Developmental
May be characterized by symptoms of inattention,
hyperactivity, and impulsivity among children placed in academic
settings that are inappropriate to their intellectual ability. Individuals
with Intellectual Disability without ADHD do not have symptoms during
nonacademic tasks. A diagnosis of ADHD in individuals with Intellectual
Disability requires that the inattention or hyperactivity be excessive
for the individual’s mental age.
Autism Spectrum Disorder
May be characterized by social disengagement
and social isolation due to deficits in social communication, as
well as temper tantrums due to an inability to tolerate a change
from the expected course of events, whereas social dysfunction and peer
rejection in ADHD are related to symptoms of inattention and hyperactivity,
and misbehavior and temper tantrums are related to impulsivity or
Disinhibited Social Engagement Disorder
Is characterized by social disinhibition,
but not the full ADHD symptom cluster. Children with Disinhibited
Social Engagement Disorder also have a history of extremes of insufficient
Disruptive Mood Dysregulation Disorder
Is characterized by pervasive irritability and
intolerance of frustration. Given that most children and adolescents
with Disruptive Mood Dysregulation Disorder also have symptoms that
meet criteria for ADHD, an additional diagnosis may be made.
May be characterized by symptoms of inattention
due to fear, worry, and rumination. In ADHD, the inattention is
because of attraction to external stimuli or new activities, or
preoccupation with enjoyable activities.
Major Depressive Disorder
May be characterized by an inability
to concentrate; however, the poor concentration is prominent only
during Major Depressive Episodes.
Bipolar I and Bipolar II Disorder
May be characterized by increased activity, poor
concentration, increased impulsivity, and distractibility, but these
features are episodic, occurring several days to weeks at a time.
Moreover, the symptoms are accompanied by elevated or irritable mood,
grandiosity, and other specific bipolar features.
Although individuals with ADHD may show significant changes in mood
within the same day, such lability is distinct from a Manic or Hypomanic
Episode, which must be sustained and last
at least a week (or 4 days for a Hypomanic
Episode) to be a clinical indicator of Bipolar I or Bipolar II Disorder.
Borderline, Antisocial, and Narcissistic Personality
Share the features of disorganization,
social intrusiveness, emotional dysregulation, and cognitive dysregulation.
These disorders are distinguished from ADHD by the presence of additional
maladaptive features, such as self-injury, antisocial behavior,
fear of abandonment, and lack of empathy. If criteria are met for both
ADHD and a Personality Disorder, both may be diagnosed.
Medication-induced symptoms of ADHD
Are characterized by symptoms of inattention,
hyperactivity, or impulsivity caused by medications (e.g., bronchodilators,
isoniazid, neuroleptics [resulting in akathisia], thyroid replacement
medication) and remit when the medications are stopped. ADHD is
not diagnosed if the symptoms occur only during medication use.
May be characterized by cognitive impairments
similar to those in ADHD; they are distinguished by their typically
later age at onset.