A CPU acquires a distance image which indicates a distance to an imaging target and is captured by a TOF camera that captures the distance image using, as the imaging target, a mammography apparatus which is an abnormality determination target. In addition, the CPU acquires reference distance image as reference distance information related to a reference value of a distance between the abnormality determination target in a reference state and the TOF camera. Further, the CPU performs determination on an abnormality appearing in an outward appearance of the abnormality determination target on the basis of the distance image and the reference distance image.