TABLE 2.

Parameters for Total Breakpoint Dose Response Fits

Cell radiation	Model*	α (D)	β (D2)	c (Intercept)
Gamma lymphocytes	α/β	0.40 ± 0.08	0.29 ± 0.02	0.03 ± 0.06
Gamma fibroblasts	α/β	0.45 ± 0.06	0.09 ± 0.02	0.08 ± 0.04
Alpha particles fibroblasts	Linear	6.76 ± 0.37		0.21 ± 0.08
Fe ions lymphocytes	α/β	1.87 ± 0.18	1.00 ± 0.12	0.17 ± 0.05

^*By standard practice, we have fit the γ-ray data to linear-quadratic (α/β) models even though such models failed to provide a significantly better fit to the data than simple linear ones. In the case of Fe ions, an α/β model provided a significantly better fit than a simple linear one (F test, P < 0.01).