A data-integration system and an information gathering system is described for securing integrated distributed, interinstitutional medical data using security-enhanced mobile agent technology. The VEPR system consists of stationary agents that integrate documents from multiple legacy departmental systems (DISs) within one institution. ICU provides an overview of patients records by providing available clinical reports. The VEPR system consists of three modules which include the multiagent system for integration of data (MAID), the clinical central information repository (CRep), and the visualization module (VIZ). The multiagent system automatically retrieves document references and actual documents, while the VIZ presents patient data upon user request. The system expresses references to documents such as clinical reports and discharge letters as uniform resource identifiers which can be collected by direct access, using HTTP, using FTP, or through a Web service.