**3.1 Calculation of isoefficient doses**

It is necessary to find the value of dose per fraction for a regimen isoeffective to the classical (2 Gy per fraction in 30 fractions), implemented in 18 fractions every other day, taking into account early reactions (α/β = 10 Gy) and late complications (α/β = 3 Gy). The total treatment time does not change.

For the solution, it is necessary to fill in the active cells with data in the form as it is required in the task (**Figure 2**). Further, after filling in the *Treatment schedule*, simulate irradiation every other day. To do this, unnecessary fractions must be removed with a mouse click. The result is the value inside the calendar cells. This is 2.85 Gy for late complications of alpha beta 3 Gy. For early reactions, change the value of alpha beta to 10 and get the result of 3.06 Gy.
