Gøtzsche P C, Lange B
Medical Department A, Rigshospitalet, Copenhagen.
Dan Med Bull. 1991 Dec;38(6):476-8.
To minimise the effect of reference bias in literature retrieval, it is important to use computerised search strategies that give a high yield of relevant reports. In a MEDLINE search that included the Medical Subject Heading (MeSH) "Comparative study," the recall of double-blind trials of NSAIDs in rheumatoid arthritis was 93.1% (122/131) and the precision was 19.0% (122/641). When "Double-blind method" was used, either as MeSH or text words, the recall was only 72.5% (95/131) with a precision of 22.7% (95/419). A combined search strategy increased the recall to 97.7% (128/131) with a precision of 17.3% (128/738). With the MeSH term "Random allocation" only eight relevant reports were retrieved, and none was new. By using "Clinical trials" alone, we would have missed eleven reports. We conclude that "Comparative study" is preferable to "Double-blind method" when searching double-blind trials on MEDLINE.
为尽量减少文献检索中引用偏倚的影响，采用能大量获取相关报告的计算机检索策略很重要。在一项包含医学主题词（MeSH）“比较研究”的MEDLINE检索中，类风湿关节炎中非甾体抗炎药双盲试验的召回率为93.1%（122/131），精确率为19.0%（122/641）。当使用“双盲法”作为MeSH或文本词时，召回率仅为72.5%（95/131），精确率为22.7%（95/419）。联合检索策略将召回率提高到97.7%（128/131），精确率为17.3%（128/738）。仅使用MeSH词“随机分配”时，仅检索到8篇相关报告，且无新报告。仅使用“临床试验”，我们会遗漏11篇报告。我们得出结论，在MEDLINE上检索双盲试验时，“比较研究”比“双盲法”更可取。
