Sato Kenichiro, Toda Tatsushi, Iwata Atsushi
Department of Neurology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan.
Department of Neurology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan.
J Stroke Cerebrovasc Dis. 2019 May;28(5):1290-1294. doi: 10.1016/j.jstrokecerebrovasdis.2019.01.015. Epub 2019 Feb 12.
The fragility index (FI), a minimum number of events in 1 arm of a clinical trial required to revert the statistically significant result to nonsignificant, has recently been developed as an easy-to-understand novel metric to evaluate the robustness of randomized controlled trials (RCTs). Here, we evaluated the FI of RCTs in the field of neurology, particularly in studies of ischemic stroke.
Previous literature published between June 1, 2012 and May 31, 2018 were reviewed from the MEDLINE database by the authors. The original article reporting the significant RCT result, of which a dichotomous outcome was set as its primary outcome measure, was included to evaluate the robustness of the result by calculating the FI. In addition, recent studies examining FI in other clinical fields were reviewed and summarized.
In the 25 eligible RCT studies, the median total number of study participants was 206 (inter quartile range: 144-450) and the median FI was 7 (inter quartile range: 4-15.0). The FI showed a strong negative correlation with the observed P value. There was no significant difference in the FI between RCTs with and without acute settings. Our median FI was higher than the median FI of 2.5 of previous studies examining FI in other clinical fields, as only 20% (5 of 25) of studies included in our study had an FI less than 2.5.
Our results suggest that many RCTs in the field of ischemic stroke have a fair robustness, when compared to those in other clinical fields.
脆弱性指数（FI）是临床试验中一组中使具有统计学意义的结果转变为无统计学意义所需的最少事件数，最近已被开发为一种易于理解的新型指标，用于评估随机对照试验（RCT）的稳健性。在此，我们评估了神经病学领域RCT的FI，特别是在缺血性卒中研究中。
作者从MEDLINE数据库中检索了2012年6月1日至2018年5月31日期间发表的既往文献。纳入报告了具有显著意义的RCT结果的原始文章，其将二分结果设定为主要结局指标，通过计算FI来评估结果的稳健性。此外，还对近期其他临床领域中研究FI的研究进行了综述和总结。
在25项符合条件的RCT研究中，研究参与者的总数中位数为206（四分位间距：144 - 450），FI中位数为7（四分位间距：4 - 15.0）。FI与观察到的P值呈强负相关。有急性情况和无急性情况的RCT之间的FI无显著差异。我们的FI中位数高于既往其他临床领域研究FI时2.5的中位数，因为我们研究中纳入的研究仅有20%（25项中的5项）的FI小于2.5。
我们的结果表明，与其他临床领域的RCT相比，缺血性卒中领域的许多RCT具有相当的稳健性。
