Faculty of Health, School of Medicine, Health Policy and Practice, University of East Anglia, Norwich, United Kingdom.
J Clin Epidemiol. 2011 Apr;64(4):349-57. doi: 10.1016/j.jclinepi.2010.04.022.
To evaluate the measures taken to deal with publication bias across different categories of systematic reviews published in 2006 and to compare these with reviews published in 1996.
PubMed was searched for systematic reviews published in 2006; 100 treatment effect, 50 diagnostic accuracy, 100 risk factor, and 50 gene-disease association reviews were randomly selected.
The use of MEDLINE increased from 74% to 95%; checking references increased from 42% to 73%; use of Cochrane Library increased from 5% to 58%; and use of CINAHL increased from 8% in 1996 to 24% in treatment reviews, 20% in diagnostic reviews, 18% in risk factor reviews, and 0% in genetic reviews published in 2006. A 20% increase was observed for explicit searching of non-English-language studies in all reviews published in 2006. Efforts to search for unpublished studies increased to 61% from 35% in treatment reviews published in 1996. Twenty-six percent of the reviews used funnel plots or related methods to test for publication bias compared with less than 6% in earlier reviews.
Recent reviews show a significant improvement in the measures taken to prevent publication bias. However, few methods exist to deal with publication bias in the nonquantitative findings of systematic reviews.
评估 2006 年发表的不同类型系统评价中为处理发表偏倚而采取的措施，并与 1996 年发表的评价进行比较。
在 PubMed 中检索 2006 年发表的系统评价，随机选择 100 篇治疗效果、50 篇诊断准确性、100 篇危险因素和 50 篇基因-疾病关联评价。
使用 MEDLINE 的比例从 74%增加到 95%；检查参考文献的比例从 42%增加到 73%；使用 Cochrane Library 的比例从 5%增加到 58%；使用 CINAHL 的比例从 1996 年的 8%增加到 2006 年治疗评价中的 24%、诊断评价中的 20%、危险因素评价中的 18%和遗传评价中的 0%。所有 2006 年发表的评价中，明确检索非英语语言研究的比例增加了 20%。寻找未发表研究的努力从 1996 年治疗评价中的 35%增加到 61%。与早期评价相比，有 26%的评价使用漏斗图或相关方法来检验发表偏倚，而少于 6%的评价使用了这些方法。
最近的评价表明，为防止发表偏倚而采取的措施有了显著的改善。然而，在系统评价的非定量发现中，处理发表偏倚的方法很少。
