A data communication system for handling confidential medical-related information, where a plurality of data analysis apparatuses are communicatively coupled to one another, each data analysis apparatus including a storage unit and a control unit, wherein the storage unit includes: a database arranged to store medical-related data, and the control unit includes: a data accessing unit arranged to access the database at a given access level, wherein the medical-related data stored in the database includes accessible data and data to which the access is restricted depending on the access level given to the data accessing unit; a program executing unit arranged to execute an application program based on the medical-related data acquired from the database via the data accessing unit to perform data analysis; and a communication controlling unit arranged to perform communication control to allow transmission and reception of a data analysis result by the program executing unit with respect to another of the data analysis apparatuses where the access level is different, wherein while the program executing unit is arranged to execute the application program in a master mode, the program executing unit of another of the data analysis apparatuses is arranged to execute the application program in a slave mode based on acquisition of the medical-related data depending on the access level at the master side via the data accessing unit, wherein the data accessing unit includes a micromodule group arranged to access the database at respective different access levels such that analysis can be performed by different program executing units of respective data analysis apparatuses among the plurality of data analysis apparatuses with different access levels without reconfiguration. a database arranged to store medical-related data, and the control unit includes: a data accessing unit arranged to access the database at a given access level, wherein the medical-related data stored in the database includes accessible data and data to which the access is restricted depending on the access level given to the data accessing unit; a program executing unit arranged to execute an application program based on the medical-related data acquired from the database via the data accessing unit to perform data analysis; and a communication controlling unit arranged to perform communication control to allow transmission and reception of a data analysis result by the program executing unit with respect to another of the data analysis apparatuses where the access level is different, a data accessing unit arranged to access the database at a given access level, wherein the medical-related data stored in the database includes accessible data and data to which the access is restricted depending on the access level given to the data accessing unit; a program executing unit arranged to execute an application program based on the medical-related data acquired from the database via the data accessing unit to perform data analysis; and a communication controlling unit arranged to perform communication control to allow transmission and reception of a data analysis result by the program executing unit with respect to another of the data analysis apparatuses where the access level is different, wherein while the program executing unit is arranged to execute the application program in a master mode, the program executing unit of another of the data analysis apparatuses is arranged to execute the application program in a slave mode based on acquisition of the medical-related data depending on the access level at the master side via the data accessing unit, wherein the data accessing unit includes a micromodule group arranged to access the database at respective different access levels such that analysis can be performed by different program executing units of respective data analysis apparatuses among the plurality of data analysis apparatuses with different access levels without reconfiguration.