Differentiating ADD from ADHD in Adolescents
The terminology "ADD" is outdated and no longer used in current diagnostic frameworks—ADHD is now classified into three presentations: predominantly inattentive, predominantly hyperactive-impulsive, or combined type, all diagnosed using identical DSM-5 criteria with the key distinction being which symptom cluster predominates. 1
Understanding the Diagnostic Framework
The distinction you're asking about reflects older terminology. What was previously called "ADD" is now termed ADHD, predominantly inattentive presentation. 1 The diagnostic process doesn't differentiate between "ADD" and "ADHD" as separate conditions—rather, you're determining which ADHD presentation the adolescent has based on their symptom pattern. 1
Core Diagnostic Criteria for All ADHD Presentations
You must establish that symptoms were present before age 12, even if the adolescent is being evaluated for the first time in adolescence. 1 This is non-negotiable for diagnosis and helps distinguish ADHD from conditions that emerge later, such as depression or substance-induced symptoms. 1
Required Documentation Steps:
- Obtain information from at least 2 teachers or other observers (coaches, school counselors, community activity leaders) plus parents/guardians to document cross-setting impairment. 1
- Verify at least 5 symptoms (for adolescents ≥17 years; 6 symptoms for younger adolescents) present for at least 6 months in multiple settings. 1
- Document functional impairment in academic, social, or occupational domains across more than one major setting. 1
Determining the ADHD Presentation Type
Predominantly Inattentive Presentation (formerly "ADD"):
Look for symptoms such as:
- Failing to give close attention to details or making careless mistakes in schoolwork
- Difficulty sustaining attention in tasks or activities
- Not seeming to listen when spoken to directly
- Not following through on instructions and failing to finish schoolwork
- Difficulty organizing tasks and activities
- Avoiding tasks requiring sustained mental effort
- Losing things necessary for tasks
- Being easily distracted by extraneous stimuli
- Being forgetful in daily activities 1
Predominantly Hyperactive-Impulsive Presentation:
Look for symptoms such as:
- Fidgeting or squirming in seat
- Leaving seat when remaining seated is expected
- Running or climbing inappropriately (or feelings of restlessness in adolescents)
- Unable to engage in leisure activities quietly
- Being "on the go" or acting as if "driven by a motor"
- Talking excessively
- Blurting out answers before questions are completed
- Difficulty waiting turn
- Interrupting or intruding on others 1
Combined Presentation:
Meets criteria for both inattentive and hyperactive-impulsive symptoms. 1
Critical Adolescent-Specific Considerations
Adolescents are less likely to exhibit overt hyperactive behavior compared to younger children, making the predominantly inattentive presentation easier to miss. 1 Some problems experienced by children with ADHD become less obvious in adolescents because hyperactivity manifests more subtly. 1
Adolescents' self-reports often differ from other observers because they tend to minimize their own problematic behaviors. 1 This makes collateral information from teachers and parents essential rather than optional. 1
Variability in ratings between different teachers is expected because adolescents' behavior often varies between classrooms and with different teachers—identifying reasons for this variability provides valuable clinical insight. 1
Mandatory Screening for Mimicking Conditions
Before finalizing any ADHD diagnosis, you must screen for conditions that can mimic or coexist with ADHD, as the majority of adolescents with ADHD-like symptoms meet criteria for another mental disorder. 1, 2
Conditions That Mimic Inattention/Impulsivity:
Substance use (particularly marijuana) produces effects that mimic ADHD symptoms including impulsivity and inattention. 1, 2 Adolescents may also feign ADHD symptoms to obtain stimulant medications for performance enhancement. 1, 2
Depression and anxiety disorders share hyperarousal features with ADHD but lack the pervasive pattern present since before age 12. 2, 3 Approximately 14% of children with ADHD have comorbid anxiety disorders, with rates increasing with age. 2, 3
Post-traumatic stress disorder (PTSD) can manifest with impulsivity, hyperarousal, and attention difficulties that closely mimic ADHD symptoms, but develops after traumatic exposure and includes trauma-specific reexperiencing and avoidance that ADHD lacks. 2, 3
Sleep disorders (including sleep apnea) produce daytime hyperactivity, inattention, and impulsive behavior that resolves with treatment of the underlying sleep problem. 1, 2
Learning disabilities and language disorders commonly present with inattention and behavioral dysregulation that appears impulsive. 1, 2
Common Diagnostic Pitfalls to Avoid
Failing to obtain information from multiple settings before concluding ADHD criteria are met leads to misdiagnosis. 2 Single-source reporting (parent-only or teacher-only) is insufficient. 1
Assigning an ADHD diagnosis when symptoms are better explained by trauma, substance use, or other psychiatric conditions results in inappropriate treatment. 2, 3 The risks of mood and anxiety disorders, risky sexual behaviors, intentional self-harm, and suicidal behaviors all increase during adolescence. 1
Not establishing that symptoms were present before age 12 in adolescents leads to misdiagnosis of conditions that emerged later. 1, 2 This temporal criterion is essential for distinguishing ADHD from adolescent-onset conditions. 1
Relying solely on the adolescent's self-report without corroborating information produces diagnostic errors because adolescents minimize their problematic behaviors. 1
Practical Assessment Algorithm
Verify age of onset: Confirm documented manifestations of inattention or hyperactivity/impulsivity before age 12 through parent report, old report cards, or previous evaluations. 1
Obtain multi-source information: Collect DSM-5-based ADHD rating scales from at least 2 teachers plus parents/guardians. 1
Document cross-setting impairment: Verify functional impairment in at least 2 settings (home, school, social activities). 1
Screen for mimicking conditions: Systematically evaluate for substance use, depression, anxiety, PTSD, sleep disorders, and learning disabilities. 1, 2
Determine symptom pattern: Count inattentive versus hyperactive-impulsive symptoms to classify presentation type. 1
Engage the adolescent: Ensure the adolescent agrees with and participates in the evaluation for it to be successful. 1