close to significancep = 0.06
Investigating the ideal timepoint for discrimination of response by building the model with an increasing number of fractions resulted in no clear optimum but was close to significance at five (β 3 = 0.076 (CI [-0.001,0.153], p = 0.06)) and ten fractions (β 3 = 0.034 (CI [0.000,0.068], p = 0.05)), and then stabilised after around thirteen fractions ( Fig. 4A ).