IMHO the most important thing is to always have positive reasons for your desire for a new job. Always present it as moving toward something you want, not as running away from something you don’t want.
You can say that you’ve been working with patients for however many years, and need a change. Everyone gets tired of things after a while, they can’t take anything negative from that. You can also say that you are in the right spot in your career for a transition into a more regular office environment.
You can say that you are detail oriented and like working with data and feel that your nursing background can help you put all that data into context.
As long as you are focused during the interview on how you can use your experience to help that group, you’ll be fine. Good luck!