生物与医学2020bmj.com
择期手术的手术日星期与术后30天死亡率
Day of week of procedure and 30 day mortality for elective surgery (2013)
入门 · 约 30 分钟读完前置知识：基础统计学、观察性研究与混杂因素概念
导读
这篇 BMJ 论文研究了英国择期手术的手术日（星期几）与 30 天死亡率之间的关系。研究发现死亡风险从周一到周四逐渐上升，周五比周一高约 44%，周末比周一高约 82%。作者指出行政数据无法完全校正择期手术安排中固有的选择偏差。
HN 关注点：标题党问题：提交标题把'30 天死亡率'曲解为'成功率翻倍'，讨论焦点集中在统计结论的准确解读以及选择偏差等混杂因素上。
HN 评论精选
这几条评论里：质疑 2 补充 2
补充纠正标题误读：研究测的是死亡率，周五比周一高 44%，周末高 82%。
标题措辞很差。研究者研究的是死亡率，而不是手术成功率。既然是择期手术，成功率应该很高——如果基线成功率是 90%，'提高 2 倍'是什么意思？研究的实际结论是：周五的死亡几率比周一高 44%，周末比周一高 82%。死亡几率从周一到周四逐渐上升，但周五大幅跳升，周末再次跳升。
savagedata查看英文原文
> Choosing Monday for a surgery increases your chance of success 2 times The title seems poorly worded. The researchers studied mortality rate, not success of procedures. Since these were elective surgeries, I assume the success rate was high. If your surgery has a baseline success rate of 90%, what would it mean to increase that 2 times? The conclusion of the study was instead that the odds of death were 44% higher on Friday compared to Monday, and 82% higher on the weekend compared to Monday. Basically, there was a gradual increase in the odds of death from Monday to Thursday, but a big jump up on Friday and again on the weekend.
质疑选择偏差可能是主要解释：不同日期安排的手术患者本身不同。
几乎可以肯定选择偏差起了主要作用——安排在周初的手术和安排在周晚的手术本身就不一样。
glofish查看英文原文
Almost certainly the selection bias plays a major role - surgeries done early in a week are different than those scheduled later in the week.
补充用具体数字说明：0.75% 的死亡率下，'成功率翻倍'的说法毫无意义。
呃，我猜他们实际想说的是失败率减半。3 万死亡 / 400 万例手术是 0.75% 的死亡率，从 99.25% 存活率提高到 99.6% 根本不是翻倍。而且文章里根本没出现'success'这个词，他们测的应该是'30 天死亡率'。
awinter-py查看英文原文
uhh guessing it halves the % of failures is what they actually mean 30k deaths / 4 million procedures is 0.75% death rate going from 99.25% to 99.6% survival isn't doubling anything also 'success' doesn't appear anywhere in this article, guessing '30 day mortality' is the thing they're measuring
质疑标题严重歪曲研究内容：这是相关性观察，不是因果结论，很多效应可能来自混杂因素。
虽然明白这是想突出'要点'，但提交标题严重歪曲了研究的实际内容。研究分析的不是手术'成功'，而是'（几乎）任何原因的 30 天死亡率'。而且研究并没有评估'主动选择周一'这一因果因素——各种压力都可能使不同星期几的择期手术具有不同的风险因素。正如作者所说：'使用行政数据的一个弱点是我们无法完全校正周末安排的择期手术中可能存在的选择偏差。'我可以相信存在患者选择或员工疲惫、术后并发症发生在资源不足的周末等效应，但预计这里发现的很多效应来自把某些手术/死亡推到某些日子的因素。
gojomo查看英文原文
While I recognize it's an attempt to highlight the "takeaway", the submission title (currently "Choosing Monday for a surgery increases your chance of success 2 times") seriously distorts the actual study contents. It's not analyzing "success" of the surgery, but "30-day mortality for (almost) any cause". (While death caused by the surgery is definitely failure, the absence of death isn't necessarilt "success".) Also, there's no evaluation of "consciously choosing Monday" as a causal factor. There could be all sorts of pressures causing the surgeries on different days-of-the-week to have different risk factors, even if they're all "elective". (As they note: "One of the weaknesses of using administrative data is that we were unable to completely adjust for inherent selection biases that probably exist for elective procedures that are scheduled on weekends.".) I can believe there's some effect of patient choice, possibly related to staff exhaustion, post-op complications happening during under-resourced weekends, but expect a lot of the effect found here to be due to factors pushing certain surgeries/deaths into certain days (and arbitrary categories that might have affected inclusion).
历次讨论
- 2020Hacker News 讨论帖188 分 · 83 评
同领域还值得读
CRISPR 在活体动物中消除 HIV-1 感染
CRISPR eliminates HIV-1 infection in live animals
报告利用 CRISPR/Cas9 基因编辑技术在活体动物中清除 HIV-1 感染：研究人员通过腺病毒载体递送特定的 Cas9 系统，从被感染细胞中切除嵌入的 HIV 病毒 DNA。
生物与医学2017 · 1,455 分 · 239 评入门 · 约 30 分钟编辑精选保护区飞行昆虫生物量27年下降75%
75% decline over 27 years in total flying insect biomass in protected areas
这篇发表于 PLOS ONE 的研究通过在德国保护区长达 27 年的昆虫生物量监测，发现飞行昆虫总量下降了约 75%。
生物与医学2017 · 901 分 · 432 评入门 · 约 45 分钟编辑精选为什么大多数已发表的研究发现是错的
Why Most Published Research Findings Are False (2005)
这篇 2005 年发表于 PLOS Medicine 的经典论文由 John Ioannidis 撰写，论证了在统计功效不足、研究偏倚和多重检验等因素下，大多数已发表的医学研究发…
生物与医学2022 · 388 分 · 351 评入门 · 约 60 分钟编辑精选人类免疫系统的物理接线图
A physical wiring diagram for the human immune system
这篇 Nature 论文系统绘制了人类免疫系统的“物理接线图”：通过大规模实验鉴定免疫细胞表面受体之间的相互作用（包括约 30 种此前未知的受体互作），并结合定量计算模型模拟免疫…
生物与医学2022 · 342 分 · 49 评专业 · 约 90 分钟编辑精选脂肪组织在减重后仍保留肥胖的表观遗传记忆
Adipose tissue retains an epigenetic memory of obesity after weight loss
这篇 Nature 论文研究了肥胖对脂肪组织的长期影响：即使减重成功，脂肪细胞仍保留着肥胖时期的表观遗传记忆，可能解释为什么减重后容易反弹。
生物与医学2025 · 263 分 · 327 评进阶 · 约 45 分钟编辑精选