Provided is a diagnostic support program that can display the movement of an area that changes shape with each respiration element that includes all or part of an inhale or an exhale. The program includes: processing in which a plurality of frame images are acquired from a database that stores images; processing in which the period of a respiration element that includes all or part of an inhale or an exhale is specified on the basis of the pixels in a specific area of the frame images; processing in which a lung field is detected on the basis of the specified period of the respiration element; processing in which the detected lung field is partitioned into a plurality of block areas, and the change in the block areas of the frame images are calculated; processing in which a Fourier transform is performed on the change in the block areas of the frame images; processing in which, of the spectra obtained after the Fourier transform, the spectra that are within a fixed band that includes the spectrum that corresponds to the period of the respiration element are extracted; processing in which an inverse Fourier transform is performed on the spectra extracted from the fixed band; and processing in which post-inverse-Fourier-transform images are displayed on a display.