Radiation dose dependences in the atomic bomb survivor cancer mortality data: A model-free visualization

The standard approach to obtaining nominal risk coefficients for radiation- related cancer involves fitting linear or linear-quadratic dose-response fu nctions. This is usually complemented by a more direct visualization where the data are subdivided into distinct dose categories and the effect level is quantified for each of these categories. Such model-free computations, h owever, can be quite dependent on the arbitrary choice of the cutpoints in dose. The method proposed here largely avoids this arbitrariness by choosin g a dose category width-constant on a log scale-to obtain the desired degre e of smoothing, and then superimposing results for all placements of the re sulting log-dose grids, The method is applied to leukemia and solid cancer mortality of the A-bomb survivors. (C) 2000 by Radiation Research Society.