Provided is a data analysis technique that uses an MRS spectrum obtained by MRS measurement, enabling a simple and a highly precise diagnostic support. This technique determines similarity between a record of the spectrum database on a disease basis being created in advance, and analysis data of an unknown MRS spectrum being newly acquired, thereby presenting a candidate disease. Determination of the similarity employs, out of the analysis data, only the data including a reliability index that satisfies a predetermined condition, as to each predetermined feature item. Similarly, creation of the spectral database on a disease basis employs, out of the analysis data containing at least one MRS spectrum with a definitive diagnosis, only the data including the reliability index that satisfies a predetermined condition, as to each predetermined feature item.