A notice of the Ministry of Health, Labour and Welfare of July 1, 2019 deals with kensan, the study doctors do on their own outside scheduled hours. Study that is not essential to the work, done of free will, outside working hours, offered by the doctor on his or her own initiative, and without express or implied instruction from a superior is generally not working time, even at the hospital.
Preparation for treatment and follow-up work that is essential to treatment count as working time.