A recording unit holds a plurality of examination data including the examination date of a performed examination. A search unit extracts examination data matching a set condition, of the plurality of examination data held in the recording unit. An output unit outputs a search result by the search unit. A first narrowing unit extracts examination data in which the examination date is included within a designated first period. A reference data determination unit classifies the examination data extracted by the first narrowing unit by an examinee and determines, for every examinee, one piece of the examination data to be a reference in accordance with a predetermined rule. A second narrowing unit sets, for every examinee, a second period designated in at least one of the past direction and the future direction starting from a reference date that is the examination date of the examination data determined by the reference data determination unit and extracts examination data in which the examination date is included within the second period.