A precedent database is generated by registering location indicating information that shows location of each of a plurality of precedent data. A knowledge database is generated by repeating processes of carrying out a search of this precedent database according to a specified condition formula and registering knowledge names representing results of the search in correlation with the condition formula. Component and failure names in the knowledge database are inserted as items of a generated FMEA sheet. Items of the FMEA sheet are specified and displayed such that corresponding text data can be referenced.