When I call my doctor's office, I speak with a nurse, or I leave a message and a nurse calls me back. After talking to me, the nurse may consult with the doctor

When I call my doctor's office, I speak with a nurse, or I leave a message and a nurse calls me back. After talking to me, the nurse may consult with the doctor and call me back, or if necessary, the doctor might call me. I can also email, and I have no idea if emails are directly answered by the doctor or if there is some kind of delegation going on there too.