How Harry helps kids

Although the article linked above is a couple of years old, it seemed the most appropriate one out of my PubMed search results (I searched for Harry Potter).

The last book of the Harry Potter series, Harry Potter and the Deathly Hallows, was released yesterday. Gwilym and colleague's study showed that the release of the previous two books (The Order of the Phoenix and The Half-Blood Prince) caused a dip in the number of accident-related admissions to their emergency department. Presumably, kids were temporarily more sedentary as they read the latest editions.

They conclude:

It may therefore be hypothesised that there is a place for a committee of safety conscious, talented writers who could produce high quality books for the purpose of injury prevention.

but...

Potential problems with this project would include an unpredictable increase in childhood obesity, rickets, and loss of cardiovascular fitness.

As for myself, I did not injure myself while running in to pick up my copy, despite the ground being wet, but I did get up after finishing the book and find that my knee had popped out of place. So there are some hazards.