The problem with any survey of this kind is that it's extremely difficult to tell just how bad the problem is. Women who have been hit by their partners can be anything from an instantly regretted slap once in a heated argument where both parties lost their temper, to horrific acts of systematic violence. We also don't know how many people know of the same act, and how many incidents were genuinely made up by the couple. On the other end of the scale, there may be incidents going on that no-one knows about (or where people know but don't tell anyone, not even an anonymous survey) that inflate the figures.
Similar arguments can be made about women coerced or pressured into sex.
This isn't meant to trivialise the issue - rape and domestic abuse are both horrific - and, to be fair, this survey keeps the issue in the public eye, but I'm not sure it tells us for definite anything we don't know already.
[However, I think everybody who's anybody agrees the domestic violence against women is more widespread than domestic violence against men. Although both are equally unacceptable, and unfortunately society is, if anything, even more tolerant of domestic violence against men.]