Department of Anesthesiology, Northwestern University Feinberg School of Medicine, Chicago, IL, USA.
Anesth Analg. 2012 May;114(5):1042-8. doi: 10.1213/ANE.0b013e3182468fc6. Epub 2012 Feb 17.
Publication bias occurs because positive finding studies are more likely to be published. The dearth of studies of negative or equivalence findings can erroneously affect future research and potentially clinical care of patients. We hypothesized that positive studies were more likely to be published than negative studies in anesthesiology journals with a higher impact and circulation.
A PubMed search for controlled trials in humans published in peer-reviewed anesthesiology journals during 2008 and 2009 was performed. Fourteen anesthesiology journals and 1163 studies were evaluated. The average clinical trial impact factor (average citations per article) for each journal was determined. The quartiles for the clinical trial impact factor for the journals included in the analysis were 4, 6.1, and 9.1. Studies were scored by 2 raters as positive or negative results of the primary stated outcome. Factors previously associated with publication were also extracted. The primary outcome, the proportion of positive and negative studies in the journals in the upper quartile of the clinical trial impact factor to the lower quartiles was compared using the Fisher exact test. The odds ratio for the effect of positive study results adjusted for other characteristics associated with publication was determined using binary logistic regression. A multinomial logistic regression model was fitted for the journals with an impact factor in the upper quartile with adjustment for study trial registration, origin of publication, positive study findings, reporting of treatment blinding, reporting of subject withdrawals, study sponsorship, and description of the randomization method.
Positive finding studies were identified in 72% (425 of 588) of articles in journals with a clinical trial impact factor >9.1 compared with 53% (308 of 575) in journals <9.1 (P < 0.001). After adjusting for factors associated with publication, positive study results had an odds ratio (95% confidence interval) of 2.28 (1.76-3.01) for publication in an anesthesiology journal in the upper quartile. Multinomial logistic regression identified positive study findings associated with an increased likelihood of publication in 3 of the 4 anesthesiology journals with a clinical trial impact factor >9.1.
This study reports the presence of publication bias in the anesthesiology literature especially in higher clinical trial impact factor journals. Publication bias can have potential implications for future research and the clinical care of patients. Authors should be encouraged to submit negative studies to high impact journals and the journals should be encouraged to evaluate the editorial process as the cause of publication bias.
发表偏倚是由于阳性发现的研究更有可能被发表。缺乏阴性或等效结果的研究可能会错误地影响未来的研究，并可能影响患者的临床治疗。我们假设在影响因子和发行量较高的同行评审麻醉学期刊中，阳性研究比阴性研究更有可能被发表。
对 2008 年和 2009 年发表在同行评审麻醉学期刊中的人类对照试验进行了 PubMed 检索。评估了 14 种麻醉学期刊和 1163 项研究。确定了每个期刊的平均临床试验影响因子（每篇文章的平均引用次数）。分析中包含的期刊的临床试验影响因子四分位数为 4、6.1 和 9.1。由 2 名评分者对主要研究结果为阳性或阴性的研究进行评分。还提取了先前与发表相关的因素。使用 Fisher 精确检验比较期刊中处于临床试验影响因子四分位数较高的期刊和较低的期刊中阳性和阴性研究的比例。使用二元逻辑回归确定调整与发表相关的其他特征后阳性研究结果的效果的优势比。使用多变量逻辑回归模型对影响因子处于四分位值以上的期刊进行拟合，调整研究试验注册、出版来源、阳性研究结果、治疗盲法报告、受试者退出报告、研究赞助和随机化方法描述。
在临床试验影响因子>9.1 的期刊中，阳性发现研究占 72%（425/588），而在临床试验影响因子<9.1 的期刊中占 53%（308/575）（P<0.001）。在调整了与发表相关的因素后，阳性研究结果在影响因子处于四分位值以上的麻醉学期刊发表的优势比（95%置信区间）为 2.28（1.76-3.01）。多变量逻辑回归确定了在影响因子>9.1 的 4 种麻醉学期刊中，阳性研究结果与发表可能性增加相关的 3 个因素。
本研究报告了麻醉学文献中存在发表偏倚，尤其是在临床试验影响因子较高的期刊中。发表偏倚可能对未来的研究和患者的临床治疗产生潜在影响。应鼓励作者向高影响力期刊提交阴性研究，鼓励期刊评估编辑过程是否为发表偏倚的原因。
