Article type
Year
Abstract
Introduction: Searching non-Anglophone databases identifies trials from journals not in sources such as MEDLINE. PSYNDEX, for example, is a German language psychological literature database containing over 100000 reports. It has not only idiosyncratic indexing but the added complication of text and indexing in more than one language. Two German medical informatics students (ML, DN) spent 3 months working with the Cochrane Schizophrenia Group searching PSYNDEX.
Objective: To identify all randomized controlled trials (RCTs) in PSYNDEX.
Methods: PSYNDEX was acquired, on one month's free trial, from SilverPlatter. English phrases, from published MEDLINE searches, were used along with the German equivalent. The precision of each search phrase was inspected. Terms with poor yield (Less than one trial: 50 reports) were discarded. Additional phrases were identified by inspecting reports of RCTs found by the first search. The searches were repeated with these phrases.
Results: 701 reports were identified and independently inspected by ML and DN. Approximately 60% of these reports were RCTs. It was difficult to improve upon the search without a prohibitive loss of precision. 27% of trials were identified by German phrases alone, 9.5% solely by English phrases, and 63% by both languages. A mono-lingual German or English searcher would find 90% or 73% of the trials respectively.
Discussion: PSYNDEX contains many trials not indexed by other databases. Careful multilingual searching of non-Anglophone databases may counter the effects of publication and language bias within reviews.
Objective: To identify all randomized controlled trials (RCTs) in PSYNDEX.
Methods: PSYNDEX was acquired, on one month's free trial, from SilverPlatter. English phrases, from published MEDLINE searches, were used along with the German equivalent. The precision of each search phrase was inspected. Terms with poor yield (Less than one trial: 50 reports) were discarded. Additional phrases were identified by inspecting reports of RCTs found by the first search. The searches were repeated with these phrases.
Results: 701 reports were identified and independently inspected by ML and DN. Approximately 60% of these reports were RCTs. It was difficult to improve upon the search without a prohibitive loss of precision. 27% of trials were identified by German phrases alone, 9.5% solely by English phrases, and 63% by both languages. A mono-lingual German or English searcher would find 90% or 73% of the trials respectively.
Discussion: PSYNDEX contains many trials not indexed by other databases. Careful multilingual searching of non-Anglophone databases may counter the effects of publication and language bias within reviews.