Good luck Nicky, I'm sure you'll walk it
My interview was for Hawkes Bay -I did a little preparation for it, but mine was very informal
Look at the job profile- pick out similarities and differences between it and what you are doing now etc. Also look at the NZ prof code and scope of practice- from what I can gather they are almost identical to the UK ones- I think NZ health care is largely based on a mixture of UK/ Australia/ US formats. Also they will like it if you know a little about Cultural Diversity, ie- health care issues for Moauri populations. If you like I can pm some links
Also RELAX duing the interview- I sat in my scruffiest pj's with a cold beer by my side- aren't phone interviews great
HTH Ali