Provided is a technique for reducing the amount of calculation and storage costs when an alignment process and/or an image quality correction process is performed on a plurality of radiological images in order to perform comparative reading. A correction amount calculation unit 22 calculates a correction amount for matching the position and/or image quality of radiological images other than a reference radiological image among a plurality of radiological images including the same photographic subject with the position and/or image quality of the reference radiological image for each of the other radiological images. A storage processing unit 28 stores the correction amount for each of the other radiological images so as to be associated with the reference radiological image.