Diagnostic Criteria for ADHD
The diagnosis of ADHD requires meeting DSM-5 criteria with symptoms causing significant impairment in at least two major settings (social, academic, or occupational), with information obtained from multiple sources including parents/guardians, teachers, and other clinicians. 1
DSM-5 Diagnostic Criteria
Symptom Presentations
- Inattentive Presentation: ≥6 inattention symptoms, <6 hyperactivity/impulsivity symptoms
- Hyperactive/Impulsive Presentation: <6 inattention symptoms, ≥6 hyperactivity/impulsivity symptoms
- Combined Presentation: ≥6 inattention symptoms, ≥6 hyperactivity/impulsivity symptoms 1
Inattention Symptoms (≥6 required)
- Fails to give close attention to details/makes careless mistakes
- Difficulty sustaining attention
- Does not seem to listen when spoken to directly
- Does not follow through on instructions/fails to finish tasks
- Poor organization
- Avoids tasks requiring sustained mental effort
- Loses things necessary for activities
- Easily distracted
- Forgetful in daily activities 1, 2
Hyperactivity/Impulsivity Symptoms (≥6 required)
- Fidgets/squirms
- Leaves seat when remaining seated is expected
- Runs/climbs inappropriately (restlessness in adolescents/adults)
- Difficulty engaging in quiet activities
- "On the go" or acts as if "driven by a motor"
- Talks excessively
- Blurts out answers
- Difficulty waiting turn
- Interrupts/intrudes on others 1, 2
Additional Diagnostic Requirements
- Several symptoms present before age 12 years (changed from age 7 in DSM-IV)
- Symptoms present in ≥2 settings (e.g., home, school, work)
- Clear evidence that symptoms interfere with functioning
- Symptoms not better explained by another mental disorder 3, 1
Age-Specific Considerations
Children (6-12 years)
- Use standardized rating scales like Vanderbilt ADHD Rating Scale completed by both parents and teachers
- Evaluate for common comorbidities including learning disabilities, anxiety, depression, and oppositional defiant disorder 3, 1
Preschool Children (4-5 years)
- Apply DSM-5 criteria with special consideration for developmental variations
- Symptoms must be more severe than typically observed in children at comparable developmental level 1
Adolescents (12-18 years)
- May have less obvious hyperactive symptoms
- Obtain information from multiple teachers when possible
- Screen for substance use, anxiety, depression, and risky behaviors
- Document symptom onset before age 12
- Be alert to potential for feigning symptoms to obtain stimulant medication 3, 1
Comorbidity Screening
The evaluation must include screening for common comorbid conditions that may affect diagnosis and treatment approach:
- Emotional/behavioral conditions: Anxiety, depression, oppositional defiant disorder, conduct disorders, substance use
- Developmental conditions: Learning disabilities, language disorders, autism spectrum disorders
- Physical conditions: Tic disorders, sleep disorders, seizure disorders 3, 1
Diagnostic Process
- Gather comprehensive information from multiple sources (parents, teachers, other clinicians)
- Document symptoms and impairment in more than one major setting
- Apply DSM-5 criteria to determine if threshold is met for diagnosis
- Screen for comorbidities that may mimic or coexist with ADHD
- Rule out alternative explanations for symptoms 3, 1
Common Pitfalls in Diagnosis
- Incomplete assessment: Failing to gather information from multiple sources and settings
- Missing comorbidities: Not screening for conditions that frequently co-occur with ADHD
- Developmental considerations: Not accounting for age-appropriate behavior variations
- Substance use in adolescents: Certain substances like marijuana can mimic ADHD symptoms
- Environmental factors: Not considering if symptoms are secondary to environmental factors rather than primary ADHD 3, 2
Differential Diagnosis
Consider other conditions that may present with similar symptoms:
- Anxiety disorders
- Mood disorders
- Learning disabilities
- Sleep disorders
- Trauma-related disorders
- Autism spectrum disorder
- Substance use disorders 3, 1
The diagnosis of ADHD should be made only after a comprehensive clinical assessment that confirms DSM-5 criteria are met and rules out alternative explanations for symptoms.