Hmmm, I had a little look at my philosophical bible (Crotty, The Foundations of Social Research) and I think what you've said is ok. It's about understanding what sense people make of the world which both interpretivism and relativism are both concerned with. BUT I would run it past your supervisors just to make sure! They'll know if it's acceptable to say this, I think it is, but then I'm quite a pragmatist really (sssh! don't tell anyone ;-) )