Het opsporen van relevante diagnostische studies in Medline: Vrije-tekstzoeken versus thesauruszoeken en de zoekterm 'huisartsgeneeskunde'

Objective To examine sensitivity and positive predictive value of Medline searching for diagnostic studies, relevant for the primary health care setting. Design Comparison of results of Medline searches with a reference standard collection of studies on two subjects; the diagnostic value of ESR estimation in discriminating between 'pathology' and 'no pathology', and the dipstick method in diagnosing urinary tract infections. Main outcome measures Sensitivity (proportion of the total number of gold standard diagnostic studies that could be identified by the search) and positive predictive value (proportion of the total number of publications retrieved by Medline that were incorporated in the gold standard). Results The combined MeSH and freetext search was more sensitive than MeSH term searching only, for both the ESR and the dipstick search. With this combined search a sensitivity of.91 and.98, and a predictive value of.10 and.67 were found for ESR and dipstick respectively. By restricting the search with keywords describing the primary health care setting the predictive value increased to 0.72/1.00 but sensitivity dropped to 0.10/0.07 (ESR/dipstick). Conclusion Combining freetext and MeSH term searching, without restriction to the primary health care setting, is a valuable strategy in systematically searching for available evidence on the value of a diagnostic test in the scope of a specific disease. The predictive value seems to depend on the breadth of the disease area. Medline should provide a term like 'diagnostic evaluation study' to be used in the limit field Publication Type to specify diagnostic studies.