Beyond relevance and recall: testing new user-centred measures of database performance

Background:  Measures of the effectiveness of databases have traditionally focused on recall, precision, with some debate on how relevance can be assessed, and by whom. New measures of database performance are required when users are familiar with search engines, and expect full text availability. Objectives:  This research ascertained which of four bibliographic databases (BNI, CINAHL, MEDLINE and EMBASE) could be considered most useful to nursing and midwifery students searching for information for an undergraduate dissertation. Methods:  Searches on title were performed for dissertation topics supplied by nursing students (n = 9), who made the relevance judgements. Measures of recall and precision were combined with additional factors to provide measures of effectiveness, while efficiency combined measures of novelty and originality and accessibility combined measures for availability and retrievability, based on obtainability. Results:  There were significant differences among the databases in precision, originality and availability, but other differences were not significant (Friedman test). Odds ratio tests indicated that BNI, followed by CINAHL were the most effective, CINAHL the most efficient, and BNI the most accessible. Conclusions:  The methodology could help library services in purchase decisions as the measure for accessibility, and odds ratio testing helped to differentiate database performance.