Conen David, Torres Jose, Ridker Paul M
Center for Cardiovascular Disease Prevention, Department of Medicine, Brigham and Women's Hospital, Boston, MA 02215, USA.
Circulation. 2008 Sep 23;118(13):1321-7. doi: 10.1161/CIRCULATIONAHA.108.794016. Epub 2008 Sep 8.
Prior work indicates that therapeutic trials funded by for-profit organizations are more likely to report positive findings than trials funded by not-for-profit organizations. What impact, if any, funding source has on subsequent dissemination of trial data is uncertain. To address this issue, we used the number of citations per publication per year to assess differences in trial dissemination according to funding source.
We assessed 303 consecutive superiority trials of cardiovascular medicine published between January 1, 2000, and July 30, 2005, in the Journal of the American Medical Association, The Lancet, and the New England Journal of Medicine. The primary outcome measure was the number of citations per publication per year up to December 31, 2006. Overall, the median number of citations per publication per year was 46 for trials funded exclusively by for-profit organizations, 37 for trials jointly funded, and 29 for trials funded by not-for-profit organizations (P=0.0007). Higher citation rates for trials funded by for-profit organizations were consistently observed in analyses stratified by journal and various trial design features and were most striking when the new intervention was favored over the standard of care; in this subgroup, the median number of citations per publication per year was 52 for trials funded by for-profit organizations compared with 25 for trials funded by not-for-profit organizations (P=0.0006). In marked contrast, in analyses limited to trials in which the new intervention was significantly worse than the standard of care, an inverse pattern was observed with fewer citations per publication per year for trials funded by for-profit organizations compared with not-for-profit organizations (33 versus 41; P=0.048). Higher citation rates were observed for industry-funded trials than for federally funded trials even when the trials dealt with similar issues and were published back-to-back in the same journal.
Dissemination of clinical trial results is important for clinical practice but appears to be biased in favor of for-profit entities. Consideration should be given to more extensive promotion of clinical trial results that are funded by not-for-profit organizations.
先前的研究表明，由营利性组织资助的治疗性试验比由非营利性组织资助的试验更有可能报告阳性结果。资助来源对试验数据随后的传播有何影响（如果有的话）尚不确定。为解决这一问题，我们使用每年每篇出版物的引用次数来评估根据资助来源的试验传播差异。
我们评估了2000年1月1日至2005年7月30日期间发表在美国医学会杂志、《柳叶刀》和《新英格兰医学杂志》上的303项连续的心血管医学优效性试验。主要结局指标是截至2006年12月31日每年每篇出版物的引用次数。总体而言，完全由营利性组织资助的试验每年每篇出版物的引用次数中位数为46次，联合资助的试验为37次，非营利性组织资助的试验为29次（P = 0.0007）。在按期刊和各种试验设计特征分层的分析中，始终观察到营利性组织资助的试验引用率更高，当新干预措施优于护理标准时最为显著；在该亚组中，营利性组织资助的试验每年每篇出版物的引用次数中位数为52次，而非营利性组织资助的试验为25次（P = 0.0006）。形成鲜明对比的是，在仅限于新干预措施明显比护理标准差的试验的分析中，观察到一种相反的模式，营利性组织资助的试验每年每篇出版物的引用次数少于非营利性组织资助的试验（33次对41次；P = 0.048）。即使试验涉及类似问题并在同一期刊上相继发表，行业资助的试验的引用率也高于联邦资助的试验。
临床试验结果的传播对临床实践很重要，但似乎偏向于营利性实体。应该考虑更广泛地推广由非营利性组织资助的临床试验结果。
