A software-based translation of that article from German to English does describe Dr. Eisenberg as the "father of ADHD" and report that during his "last interview" he said something similar to "ADHD is a prime example of a fictitious disease." However, allowing for the vagaries of translation and reading the statement in context, some native German speakers have reported that Dr. Eisenberg wasn't asserting that ADHD isn't a real disorder, but rather that it is overdiagnosed.
On a related note, an August 2012
Der Spiegel English-language
interview with (now retired) Harvard psychologist Dr. Jerome Kagan quoted Dr. Kagan as being critical of "fuzzy diagnostic practices" and the over-prescription of drugs such as Ritalin for behavioral problems in children, and as referring to ADHD as "an invention":
SPIEGEL: In the 1960s, mental disorders were virtually unknown among children. Today, official sources claim that one child in eight in the United States is mentally ill.
Kagan: That's true, but it is primarily due to fuzzy diagnostic practices. Let's go back 50 years. We have a 7-year-old child who is bored in school and disrupts classes. Back then, he was called lazy. Today, he is said to suffer from ADHD (Attention Deficit Hyperactivity Disorder). That's why the numbers have soared.