Article type
Year
Abstract
Background: It has been reported that a large number of medications are used routinely for unapproved indications or in incorrect dosages, routes of administration or age groups. These are so-called 'off-label’ uses. However, the efficacy and safety of off-label drug usage have not beensufficiently proven.
Objectives: Because of variation in the description of using medications beyond their approval and diversity in study type, the off- label drug use studies are not easyto detect in electronic literature databases. This research aimed to develop a search strategy that facilitates finding the off- label drug use studies in a bibliographic database, Ovid MEDLINE.Methods: MEDLINE via OvidSP was searched from 1948 to 20 January 2011. Search queries, including search words and strings, were conceived based on definitions of off-label use of medications.The sensitivity and specificity of search queries and their combinations as well as the subjectheading 'Off-Label Use.sh.’ were determined by comparison with a gold standard reference set. The gold standard was compiled from reports of off- label drug use identified by a sensitive search ofMEDLINE and EMBASE. We attempted to achieve the highest possible sensitive search strategy and an optimal balance of sensitivity and precision.
Results: Out of 4334 retrieved documents, 2177 (50.2%) off- label drug use studies were found. The most sensitive single term was 'off label*.af.’ (sensitivity 40.9%, precision 84.4%). A top sensitive strategy was revealed by combining 31 search queries with sensitivity of 53.3% and precision of 60.3%. Maximizing precision, a top search strategy achieved a value of 84.0%, but with compromisedsensitivity at 49.0%.
Conclusions: We empirically developed two versions of highly sensitive search strategies, which can achieve high performance for retrieving off-label drug use documents in Ovid MEDLINE.
Objectives: Because of variation in the description of using medications beyond their approval and diversity in study type, the off- label drug use studies are not easyto detect in electronic literature databases. This research aimed to develop a search strategy that facilitates finding the off- label drug use studies in a bibliographic database, Ovid MEDLINE.Methods: MEDLINE via OvidSP was searched from 1948 to 20 January 2011. Search queries, including search words and strings, were conceived based on definitions of off-label use of medications.The sensitivity and specificity of search queries and their combinations as well as the subjectheading 'Off-Label Use.sh.’ were determined by comparison with a gold standard reference set. The gold standard was compiled from reports of off- label drug use identified by a sensitive search ofMEDLINE and EMBASE. We attempted to achieve the highest possible sensitive search strategy and an optimal balance of sensitivity and precision.
Results: Out of 4334 retrieved documents, 2177 (50.2%) off- label drug use studies were found. The most sensitive single term was 'off label*.af.’ (sensitivity 40.9%, precision 84.4%). A top sensitive strategy was revealed by combining 31 search queries with sensitivity of 53.3% and precision of 60.3%. Maximizing precision, a top search strategy achieved a value of 84.0%, but with compromisedsensitivity at 49.0%.
Conclusions: We empirically developed two versions of highly sensitive search strategies, which can achieve high performance for retrieving off-label drug use documents in Ovid MEDLINE.