Originally Posted by Andrew H.
A good idea for a poll, but you left out other doctorates - M.D., J.D., DDS, D.D., Sc.D., Ed.D, etc.
and a fair few others. I have medical specialty fellowship which is kinda like US boards; our universities accept it as equivalent to a PhD so I 'voted' for that.
There will always be exceptions - people with no qualifications who read voraciously, others with many who don't (outside of their job).
However I do suspect the general trend would be towards more education = a higher probability of reading, also that people who's education leans towards the humanities will on average read more than engineers.