Fig. 2

Clonogenic survival of seven different cancer cell lines as determined by the novel approach involving power regression and interpolation. The dataset shown in Fig. 1 was used for analyses. a Double-logarithmic presentation of the clonogenic survival data. Power regression lines (C = a × Sb) for the number of colonies counted (C) in dependence of the number of cells seeded (S) are superimposed. The values for the exponents b are indicated for each fit. b Range of survival results as determined by the novel approach simulating wells with matched numbers of colonies C = 5 to 100 at different irradiation doses (grey areas depicted in a) and displayed according to Fig. 1c. c, Range of survival results as determined by the novel approach simulating wells with non-matched numbers of colonies C = 5 to 100 (grey areas depicted in a) as implied in the PE-based method and displayed according to Fig. 1c