MEDLINE SDI services: how do they compare?

INTRODUCTION: Selective dissemination of information (SDI) services regularly alert users to new information on their chosen topics. This type of service can increase a user's ability to keep current and may have a positive impact on efficiency and productivity. Currently, there are many venues available where users can establish, store, and automatically run MEDLINE searches. PURPOSE: To describe, evaluate, and compare SDI services for MEDLINE. RESOURCES: The following SDI services were selected for this study: PubMed Cubby, BioMail, JADE, PubCrawler, OVID, and ScienceDirect. METHODOLOGY: Identical searches were established in four of the six selected SDI services and were run on a weekly basis over a period of two months. Eight search strategies were used in each system to test performance under various search conditions. The PubMed Cubby system was used as the baseline against which the other systems were compared. Other aspects were evaluated in all six services and include ease of use, frequency of results, ability to use MeSH, ability to access and edit existing search strategies, and ability to download to a bibliographic management program. RESULTS: Not all MEDLINE SDI services retrieve identical results, even when identical search strategies are used. This study also showed that the services vary in terms of features and functions offered.