To the Editor We read with great interest the article by Roy et al¹ describing a new 4-Level Pulmonary Embolism Clinical Probability Score (4PEPS) to rule out pulmonary embolism (PE). As recommended by the Scientific and Standardization Committee of the International Society of Thrombosis and Hemostasis,² the authors predefined the acceptable upper limits of the 95% CI of failure rate at 1.93% and 1.88% for their 2 external validation cohorts. The authors found the failure rates and 95% CI of the 4PEPS below these predefined limits and concluded that the safety of the 4PEPS strategy was confirmed.

中文翻译：

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肺栓塞发生率极低的患者中 4PEPS 的安全性——需要多于点估计

致编辑我们饶有兴趣地阅读了 Roy 等人¹的文章，该文章描述了一种新的 4 级肺栓塞临床概率评分 (4PEPS)，可以排除肺栓塞 (PE)。根据国际血栓与止血学会科学与标准化委员会的建议²，作者将 2 个外部验证队列的 95% CI 的可接受上限定义为 1.93% 和 1.88%。作者发现 4PEPS 的失败率和 95% CI 低于这些预定义的限制，并得出结论，4PEPS 策略的安全性得到确认。