Should I step out when my teenager asks to speak to the doctor alone?

In the waiting room my fifteen-year-old said, "Please let me answer this time. And can I have a few minutes without you?"

I usually carry the appointment notes and answer quickly because I remember dates better. At the last visit the doctor asked him about sleep, and I described it before he had spoken. He told me afterward that my description wasn't what he would have said.

The clinic offers part of the appointment with the teenager alone. [The American Academy of Pediatrics explains why one-to-one time can help adolescents take part in their own healthcare](https://www.healthychildren.org/English/ages-stages/teen/Pages/One-on-One-Time-with-the-Pediatrician.aspx). I can see the point. I still worry about an important detail being missed, and I have caught myself wanting a full report afterward.

He hasn't said what he wants to discuss. How do I hand over more of the conversation while staying useful? What should we ask the clinician about confidentiality and follow-up, rather than making guesses about what either of us will be told?