The confusion between ADD (Attention Deficit Disorder) and ADHD (Attention Deficit Hyperactivity Disorder) terminology stems from historical changes in the diagnostic criteria and the evolution of the condition's understanding. In the past, there were separate diagnostic labels for two primary subtypes of attention deficit disorders: ADD and ADHD. However, in more recent times, the Diagnostic and Statistical Manual of Mental Disorders (DSM-5), published in 2013, consolidated the two subtypes into one umbrella term: ADHD.
The DSM-5 recognizes three presentations of ADHD:
Predominantly Inattentive Presentation: This presentation is often associated with what was previously referred to as ADD. Individuals with this type struggle with attention, focus, and organization but do not display significant hyperactivity or impulsivity.
Predominantly Hyperactive-Impulsive Presentation: This presentation primarily involves hyperactivity and impulsivity, without significant attention and focus issues.
Combined Presentation: This presentation includes symptoms of both inattention and hyperactivity/impulsivity, which were previously used to diagnose ADHD in the past.
As a result of this change, the term "ADD" is no longer an official diagnosis in the DSM-5. However, due to the historical use of ADD as a separate label, many people continue to use the terms "ADD" and "ADHD" interchangeably, even though they technically refer to different presentations of the same disorder.
Moreover, the term "ADD" is still prevalent in popular culture and has been widely used over the years. As a result, it's not uncommon for people to refer to both inattentive and combined presentations of ADHD as "ADD."
To sum up, the interchangeable use of ADD and ADHD occurs because of historical reasons, changes in diagnostic criteria, and the persistent use of the term "ADD" in popular culture even after it was officially replaced by ADHD in clinical settings.