Which subtype of ADHD is characterized primarily by a lack of attention?

The subtype of ADHD characterized primarily by a lack of attention is indeed the predominantly inattentive presentation. This presentation is marked by symptoms such as difficulty organizing tasks, frequent mistakes in schoolwork or other activities due to careless errors, trouble sustaining attention in tasks or play activities, and a tendency to forget daily activities. Individuals with this presentation may appear to be daydreaming or can be easily distracted by extraneous stimuli.

In contrast, the predominantly hyperactive/impulsive presentation focuses on excessive movement, fidgeting, and impulsive behaviors rather than attention deficits. The combined presentation includes both inattentive and hyperactive/impulsive symptoms, making it a blend of both types. The notion of a predominantly behavioral presentation is not a recognized subtype in the DSM-5 for ADHD, which emphasizes attention and impulse regulation as core features. Thus, the predominantly inattentive presentation accurately captures the essence of ADHD where inattention is the main issue.