Comparison and evaluation of nine bibliographic databases concerning adverse drug reactions

Few evaluations and statistical comparisons of bibliographic databases have been published. As a drug information center, we were particularly interested in databases providing references on adverse drug reactions (ADRs). Ten drugs were randomly chosen from the 2000 files at our center. Nine databases were selected according to the high frequency of references concerning ADRs: eight online systems (MEDLINE, BIOSIS, TOXLINE, Iowa Drug Information System, PASCAL, EMBASE, PHARMLINE, and International Pharmaceutical Abstracts [IPA]), and one Compact Disk Read Only Memory (CD-ROM) system (Core MEDLINE). The total number of references, the number of references from 1987 to 1989, and the number of relevant references from 1987 to 1989 were analyzed using the Friedman two-way ANOVA by ranks. The overlap between databases for only one drug, carboplatin, and the quality:cost ratio were also studied. Considering the total number of references, TOXLINE and EMBASE were significantly superior to IPA, PHARMLINE, PASCAL, and Core MEDLINE. For the period 1987-1989, EMBASE was significantly superior to PASCAL, IPA, PHARMLINE, and Core MEDLINE with regard to total number of references, and significantly superior to PASCAL, Core MEDLINE, and IPA with regard to relevance. MEDLINE, TOXLINE, and EMBASE had the best quality:cost ratio. EMBASE had the slightest overlap of references, with 53 percent of the unique references on carboplatin. This comparative evaluation showed that the ability of bibliographic databases to provide information on ADRs is dependent on both the size and the quality of each database.