The AAFP answers this question in 2019:
“Q: Under Medicare’s rules for medical review of student documentation, what must a teaching physician document when he or she agrees with the exam findings, assessment, and plan noted by the student?
A: According to Medicare, after personally re-performing the exam and medical decision making, the teaching physician may review, sign, and date the medical student’s entry in the medical record rather than re-documenting this work. Note that the physician should personally document any new or different findings or changes to the assessment and plan.”
Fam Pract Manag. 2019 Jan-Feb;26(1):30. https://www.aafp.org/fpm/2019/0100/p30.html
Also see The 2019 Medicare Documentation, Coding, and Payment Update.