Bero L A, Glantz S A, Rennie D
Institute for Health Policy Studies, University of California-San Francisco 94109.
JAMA. 1994 Jul 13;272(2):133-6.
To examine the tobacco industry's claim that publication bias against negative studies invalidates the risk assessment of environmental tobacco smoke (ETS) conducted by the US Environmental Protection Agency and other reviews of the health effects of ETS.
Determination of the number of published original research articles that tested the hypothesis that ETS exposure is associated with adverse health effects and that reported statistically significant ("positive") or nonsignificant ("negative") results; the number of articles that concluded that ETS is a health risk; and unpublished studies on the effects of ETS on health.
Articles identified by a computerized search of the medical literature supplemented with material obtained from the tobacco industry and hand searching. Articles were classified as peer-reviewed journal articles or articles from sponsored symposia.
The statistical significance of results reported in the article and whether or not the article concluded that ETS exposure is a health risk.
More symposium articles than journal articles were reviews (46% vs 6%; P = .0001). More original journal articles than original symposium articles reported the use of statistical tests (96% vs 54%; P = .0001). Of articles with statistical analyses, similar proportions of journal articles and symposium articles reported statistically significant results (57% vs 47%; P = .329). The conclusions of 80% of the original journal articles were positive, compared with 51% of the original symposium articles (P = .006).
There is no publication bias against statistically nonsignificant results on ETS in the peer-reviewed literature. The high proportion of articles in symposia that reach the conclusion that ETS is not harmful primarily results from the inclusion of review articles.
检验烟草行业的说法，即针对负面研究的发表偏倚使美国环境保护局对环境烟草烟雾（ETS）进行的风险评估以及其他关于ETS健康影响的综述无效。
确定已发表的原始研究文章数量，这些文章检验了ETS暴露与不良健康影响相关的假设，并报告了具有统计学显著性（“阳性”）或无统计学显著性（“阴性”）的结果；得出ETS是健康风险这一结论的文章数量；以及关于ETS对健康影响的未发表研究。
通过对医学文献进行计算机检索，并补充从烟草行业获得的资料以及人工检索来确定文章。文章分为同行评审期刊文章或赞助研讨会的文章。
文章中报告结果的统计学显著性以及文章是否得出ETS暴露是健康风险这一结论。
综述性文章中研讨会文章比期刊文章多（46%对6%；P = 0.0001）。报告使用统计检验的原始期刊文章比原始研讨会文章多（96%对54%；P = 0.0001）。在进行统计分析的文章中，期刊文章和研讨会文章报告具有统计学显著性结果的比例相似（57%对47%；P = 0.329）。80%的原始期刊文章得出阳性结论，而原始研讨会文章的这一比例为51%（P = 0.006）。
在同行评审文献中，不存在针对ETS无统计学显著性结果的发表偏倚。研讨会中得出ETS无害这一结论的文章比例高，主要是因为纳入了综述性文章。
