According to the Rules of The Doctoral School, PhD students are subject to periodic evaluation, which is carried out by supervisor. The first periodic evaluation is conducted a year after a doctoral student begins education. Another grades are carried out every year, for the previous academic year. After carried out the grade and recived opinion form supervisor, PhD student is shalling the periodic evaluation for the Director of the Doctoral School. The assessment ends with positive or negative result. A doctoral student may appeal against the negative result to the director of the doctoral school. Periodic Evaluation have to be submitted till 31 October current year.

You can find pattern of periodic evaluation here