To provide an art for shortening a time of data collection for creating correction data by reducing the number of radiographing times performed for creating the correction data in the creation of the correction data used for correcting the X-ray sensitivity.

This correction data creation method for correcting the sensitivity of X-ray data acquired by a detector for detecting the X-ray and a data collection part for collecting the detected X-ray data and amplifying them by a prescribed gain, acquires phantom data amplified by various gains using a prescribed time as a base time point, corrects the correction data by defining the phantom data as the correction data at the base time point and a time elapsing a prescribed time from the base time point as a correction time point, defines the corrected correction data as new correction data at the correction time point, reflects temporal variations of air data amplified by a criterion gain on the phantom data amplified by the various gains at the correction time point, and creates new correction data by reflecting the temporal variations of output ratios between the output of the criterion gain and the outputs of the various gains.