Which clinical feature best distinguishes Attention-Deficit/Hyperactivity Disorder (ADHD) Combined Type from ADHD Predominantly Inattentive Type in a 7-year-old child?

Explanation

## Distinguishing ADHD Subtypes ### Key Diagnostic Criteria **Key Point:** The DSM-5 ADHD subtypes are differentiated solely by the symptom profile met, not by age of onset, severity, or degree of impairment. | Feature | Combined Type | Inattentive Type | Hyperactive-Impulsive Type | |---------|---------------|------------------|---------------------------| | **Inattention symptoms** | ≥6 (children) | ≥6 (children) | <6 (children) | | **Hyperactivity-Impulsivity** | ≥6 (children) | <6 (children) | ≥6 (children) | | **Onset** | Before age 12 | Before age 12 | Before age 12 | | **Impairment** | Multiple settings | Multiple settings | Multiple settings | ### Why Combined Type is Distinct **High-Yield:** Combined Type requires meeting full threshold for BOTH inattention (≥6 symptoms) AND hyperactivity-impulsivity (≥6 symptoms). This is the only feature that definitively separates it from the Inattentive presentation. **Clinical Pearl:** Children with Combined Type typically present with: - Fidgeting, restlessness, difficulty sitting still - Blurting out answers, interrupting others - Concurrent difficulty with focus and organization - Often more disruptive in classroom and home settings ### Why Other Features Don't Discriminate - **Onset before age 12:** Present in ALL ADHD subtypes — not discriminating - **Functional impairment:** Required across all subtypes — not specific to Combined Type - **Difficulty with sustained attention:** Present in both Combined and Inattentive types — not discriminating [cite:DSM-5 ADHD Criteria]