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Fig. 3 | Radiation Oncology

Fig. 3

From: On the analysis of clonogenic survival data: Statistical alternatives to the linear-quadratic model

Fig. 3

Non-linear log-logistic regression of clonogenic survival data provides parameters with intuitive biological interpretation. A three- and a two-parameter log-logistic regression model were fitted to the clonogenic survival data. Trellis plot of the survival fraction versus radiation dose with fitted regression curves superimposed (a, red for the three-parameter, green for the two-parameter model). Estimated regression parameters and p-values for the log-logistic regression model (b); \(\hat {\phi }_{1}\) represents the survival fraction for which the dose approaches infinity, \(\hat {\phi }_{3}\) is a slope factor that refers to the steepness of the curve, and \(\hat {\phi }_{2}\) represents the irradiation dose that indicates a surviving fraction of 0.5 (ED50). c Plot of the cell lines in the space of \(\hat {\phi }_{2}\) and \(\hat {\phi }_{3}\)

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