TL;DR
ADD is the former name for the primarily inattentive type of ADHD — ADHD without visible hyperactivity. Today, ADHD is used for all three types: inattentive, hyperactive-impulsive, and combined. All three are assessed using DIVA-5.
Many adults still search for 'ADD', and for good reason. ADD was for decades the term for attention deficit without hyperactivity. The diagnosis has changed names, but the distinction between subtypes still makes a difference.
From ADD to ADHD: The name change
ADD (Attention Deficit Disorder) was introduced in 1980 with DSM-III, the American psychiatric diagnostic manual. In DSM-III, ADD and ADHD were two separate diagnoses: ADD without hyperactivity and ADHD with hyperactivity.
In 1994, DSM-IV merged the two diagnoses under one name: ADHD (Attention Deficit Hyperactivity Disorder), divided into three subtypes. ICD-11, used in the Danish healthcare system, likewise uses 'Attention Deficit Hyperactivity Disorder' as the umbrella term for all presentations. ADD as a standalone diagnosis no longer exists.
The three ADHD subtypes
ADHD is now divided into three subtypes, based on which symptoms dominate:
- Combined type: both inattention and hyperactivity/impulsivity. The most well-known and most frequently diagnosed form.
- Predominantly inattentive type: primarily difficulty concentrating and inattention without visible hyperactivity. This is the type formerly called ADD. Often called 'quiet ADHD'.
- Predominantly hyperactive-impulsive type: primarily restlessness and impulsivity, but without marked attention problems. This type is less common in adults.
The subtype can change over a lifetime. A child with the combined type may primarily have the inattentive type as an adult, because hyperactivity often decreases with age.
| Feature | ADHD (combined) | ADD (inattentive) |
|---|---|---|
| Hyperactivity | Yes, visible | No, or inner restlessness |
| Inattention | Yes | Yes, primary symptom |
| Impulsivity | Often pronounced | Less common |
| Typical discovery | Often in childhood | Often not until adulthood |
| Gender distribution | More men diagnosed | More women underdiagnosed |
| Assessment | DIVA-5 | DIVA-5 (same tool) |
Why 'ADD' still matters
Even though ADD is no longer an official diagnosis, many adults identify with the term. They have attention problems and difficulty concentrating, but they are not hyperactive in the classical sense. They sit still, daydream, and struggle to focus, but they don't disrupt. And that is precisely why they are overlooked and underdiagnosed, especially women.
The inattentive type is on average diagnosed later than the combined type. Many live for decades with difficulties, without knowing there is an explanation and a treatment.
Symptoms of the inattentive type (ADD)
If you recognize several of these, it may be worth getting assessed:
- Difficulty sustaining concentration, especially on tasks requiring sustained mental effort
- Forgetfulness in daily life: appointments, keys, messages
- Frequently losing things or forgetting where they were put
- Difficulty organizing tasks and planning
- Easily distracted by surroundings or own thoughts
- Daydreaming and a tendency to 'zone out'
- Slower processing speed; it takes longer to get started and finish tasks
- Avoiding or procrastinating tasks that require focus over longer periods
Want to screen yourself? Our ASRS screening takes 5 minutes and covers all subtypes, including the inattentive type.
How Alethia assesses all ADHD subtypes
Whether you identify with ADD or ADHD, the assessment process is the same. According to the Danish Health Authority's national clinical guidelines (Sundhedsstyrelsen, 2015), DIVA-5 is recommended as the diagnostic interview. It covers all DSM-5 criteria for ADHD, including inattentive symptoms.
The process follows our five-step protocol:
You start with a clinical interview and screening (approx. 2 hours, 2,900 DKK), a structured conversation about symptoms, functioning, and life history. Here we also screen for anxiety, depression, autism, and other conditions that can mimic or coexist with ADHD.
Then comes the DIVA-5 diagnostic interview (approx. 2 hours, 3,500 DKK), which systematically reviews all DSM-5 criteria, both current and childhood symptoms. We ask that you bring an informant who knew you as a child, if possible. The process concludes with a feedback session (approx. 2 hours, 3,000 DKK), where you receive a written report, psychoeducation, and a treatment plan tailored to your specific subtype.
Read more about the full process on our ADHD assessment page.
Treatment: the same regardless of subtype
Treatment options are the same for all ADHD subtypes. This applies to both the inattentive type (formerly ADD) and the combined type.
Stimulant medications like methylphenidate (e.g. Ritalin, Medikinet) and lisdexamfetamine (Elvanse) are first-line medication for all subtypes. The effect on concentration, working memory, and executive functions is well-documented regardless of whether hyperactivity is present.
Beyond medication, we offer psychoeducation and cognitive behavioral therapy (CBT), which helps build strategies for organization, planning, and managing daily life.
Comorbidity: Rarely just ADHD
Most adults with ADHD also have another diagnosis. Kessler et al. (2006, Archives of General Psychiatry) found that 70–80% have at least one comorbid condition, typically anxiety, depression, autism, or trauma-related difficulties.
A clinic that only screens for ADHD risks missing conditions that change the entire treatment plan. At Alethia, we have psychologists and psychiatrists under one roof, and we systematically screen for co-occurring conditions from the very first clinical interview.
Do you recognize yourself?
Whether you call it ADD or ADHD, we assess both. Book your first session.
Frequently asked questions
Yes, today only the term ADHD is used. ADD was the old term from DSM-III (1980) for attention deficit without hyperactivity. Since 1994, the official diagnosis has been ADHD, divided into three subtypes: combined, predominantly inattentive, and predominantly hyperactive-impulsive. What used to be called ADD corresponds to the predominantly inattentive subtype.
Yes. The predominantly inattentive subtype (formerly called ADD) involves difficulty concentrating, forgetfulness, and being easily distracted, but not necessarily visible hyperactivity. Many experience an inner restlessness instead, which isn't visible to others. This subtype is particularly underdiagnosed in women.
The assessment is the same regardless of subtype. At Alethia, we use DIVA-5, which is the Danish Health Authority's recommended diagnostic interview. It covers all DSM-5 criteria for ADHD, including the inattentive subtype. You start with a clinical interview (2,900 DKK), followed by DIVA-5 (3,500 DKK) and feedback with a diagnostic report (3,000 DKK).
Yes. Stimulant medications like methylphenidate and lisdexamfetamine work across all ADHD subtypes, including the inattentive type. The effect on concentration, working memory, and daily functioning is well-documented regardless of whether hyperactivity is present.