Purpose: SUMSearch (http://SUMSearch.uthscsa.edu) is a new method to find medical evidence that uses meta-searching and contingency searching. As SGIM is considering endorsing this product, we summarize its recent usage.

Methods: We report the results of the last 502 consecutive searches. We optimistically define a successful search as retrieving at least one article from MEDLINE.

Results: 421 (84%) of searches were successful. Previously, we reported that 22% of searches used more than two words within any one search term ("long terms") and these searches were significantly more likely to fail. Prior to the current series, SUMSearch was programmed to warn clinicians when they were about to submit long terms. In the current series, 12% of searches contained long terms and the presence of long terms was no longer a predictor of failed searches. SUMSearch now records when the MESH browser is used to select search terms. Searches used the MeSH browser in sixteen percent of searches. These searches were significantly less likely to fail (8% versus 16%). In 50% of the successful searches, clinicians clicked at least one link to a document. The median time was 155 seconds to finish selecting a median of two documents. The shortest time needed was 10 seconds to click a single document. The longest time occurred when a search that was executed, then three hours later 12 documents were clicked over 20 minutes.

Conclusion: 84% of searches retrieved at least one document. Based on the current and a previous analysis, searches that use the MeSH browser and avoid long search terms are more likely to succeed. Clinicians click documents from only 50% of successful searches. Possible explanations for not selecting documents include: perceived lack or genuine lack of germane citations, overlooking germane articles, and insufficient time to review list of documents. These results for clinicians using SUMSearch are consistent with prior research that showed 50% of literature searches done by medical librarians are able to answer clinical questions. We plan to redesign the list of citations returned by SUMSearch to facilitate review of the many citations.