CAN-SDI: experience with multi-source computer based current awareness services in the National Science Library, Ottawa.
CAN/SDI is Canada's national Selective Dissemination of Information Service offering a choice of nine data bases to its scientific and technical community. The system is based on central processing at the National Science Library combined with the utilization of decentralized expertise and resources for profile formulation and user education. Its greatest strength lies in its wide interdisciplinary quality. The major advantage of centralized processing of many data bases is that Canadians need learn only one method of profile formulation to access many files. A breakdown of services used confirms that a single tape service does not cover all the information requirements of most users. On the average each profile accesses approximately 1.5 data bases. Constant subscriber growth and a low cancellation rate indicate that CAN/SDI is and will continue to be an important element in Canada's information system.