Great question — and one we hear a lot! ADD is the old name for the Predominantly Inattentive ADHD subtype. ADD is a term that was removed from the diagnostic manual in 1994, but it is still commonly used. The correct name for the condition is now Attention Deficit Hyperactivity Disorder (ADHD).
ADHD may be considered mild, moderate, or severe depending on the number of symptoms and the extent of functional, social, or occupational impairment. Diagnosis will fall into one of three subtypes — Primarily Inattentive (PI), Primarily Hyperactive Impulsive (HI) and Combined Type (CT).