As APA's books explaining ADHD tend to draw from APA's official diagnostic criteria (DSM-5), the degree to which any particular book or off-the-shelf resource would tend to match a particular child's experience may be approximated by the degree to which that child matches the diagnostic criteria.

It is beneficial for a parent to pre-read a book prior to giving it to his/her child.

The APA factsheet on ADHD is here.
The CDC summarizes current diagnostic criteria (DSM-5) for ADHD, here.
The APA factsheet on ASD is here.
The CDC summarizes current diagnostic criteria (DSM-5) for ASD, here.

As with giftedness, a child need not exhibit all characteristics to receive the label.

Each child is unique. smile