HIS, RIS, and PACS.

In this paper the historical background of the concepts Hospital Information System, Radiology Information System, and Picture Archiving and Communication System (HIS, RIS, PACS) is presented. Next the present situation of the realization of the concepts is considered; the conceptual relation between the three is discussed. Accepting the existence of the three concepts, first the relation between HIS and RIS is analysed, next the relation between PACS and HIS/RIS is considered. It is concluded that such a relation is vital for the realization of a full-scale PACS. Moreover, it is concluded that not only data has to be exchanged but also information. The need for a generic description of an interface between the two is emphasized.