BACKGROUND The benefit of adjuvant chemotherapy(ACT)for patients with no evidence of disease after pulmonary metastasis resection(PM)from colorectal cancer(CRC)remains controversial.AIM To assess the efficacy of ACT i...BACKGROUND The benefit of adjuvant chemotherapy(ACT)for patients with no evidence of disease after pulmonary metastasis resection(PM)from colorectal cancer(CRC)remains controversial.AIM To assess the efficacy of ACT in patients after PM resection for CRC.METHODS This study included 96 patients who underwent pulmonary metastasectomy for CRC at a single institution between April 2008 and July 2023.The primary end-point was overall survival(OS);secondary endpoints included cancer-specific survival(CSS)and disease-free survival(DFS).An inverse probability of treat-ment-weighting(IPTW)analysis was conducted to address indication bias.Sur-vival outcomes compared using Kaplan-Meier curves,log-rank test,Cox regre-ssion and confirmed by propensity score-matching(PSM).RESULTS With a median follow-up of 27.5 months(range,18.3-50.4 months),the 5-year OS,CSS and DFS were 72.0%,74.4%and 51.3%,respectively.ACT had no significant effect on OS after PM resection from CRC[original cohort:P=0.08;IPTW:P=0.15].No differences were observed for CSS(P=0.12)and DFS(P=0.68)between the ACT and non-ACT groups.Multivariate analysis showed no association of ACT with better survival,while sublobar resection(HR=0.45;95%CI:0.20-1.00,P=0.049)and longer disease-free interval(HR=0.45;95%CI:0.20-0.98,P=0.044)were associated with improved survival.CONCLUSION ACT does not improve survival after PM resection for CRC.Further well-designed randomized controlled trials are needed to determine the optimal ACT regimen and duration.展开更多
BACKGROUND Esophageal variceal bleeding is a severe complication associated with liver cirrhosis and typically necessitates endoscopic hemostasis.The current standard treatment is endoscopic variceal ligation(EVL),and...BACKGROUND Esophageal variceal bleeding is a severe complication associated with liver cirrhosis and typically necessitates endoscopic hemostasis.The current standard treatment is endoscopic variceal ligation(EVL),and Western guidelines recom-mend antibiotic prophylaxis following hemostasis.However,given the impro-vements in prognosis for variceal bleeding due to advancements in the management of bleeding and treatments of liver cirrhosis and the global concerns regarding the emergence of multidrug-resistant bacteria,there is a need to reassess the use of routine antibiotic prophylaxis after hemostasis.AIM To evaluate the effectiveness of antibiotic prophylaxis in patients treated for EVL.METHODS We conducted a 13-year observational study using the Tokushukai medical database across 46 hospitals.Patients were divided into the prophylaxis group(received antibiotics on admission or the next day)and the non-prophylaxis group(did not receive antibiotics within one day of admission).The primary outcome was composed of 6-wk mortality,4-wk rebleeding,and 4-wk spontaneous bacterial peritonitis(SBP).The secondary outcomes were each individual result and in-hospital mortality.A logistic regression with inverse probability of treatment weighting was used.A subgroup analysis was conducted based on the Child-Pugh classification to determine its influence on the primary outcome measures,while sensitivity analyses for antibiotic type and duration were also performed.RESULTS Among 980 patients,790 were included(prophylaxis:232,non-prophylaxis:558).Most patients were males under the age of 65 years with a median Child-Pugh score of 8.The composite primary outcomes occurred in 11.2%of patients in the prophylaxis group and 9.5%in the non-prophylaxis group.No significant differences in outcomes were observed between the groups(adjusted odds ratio,1.11;95%confidence interval,0.61-1.99;P=0.74).Individual outcomes such as 6-wk mortality,4-wk rebleeding,4-wk onset of SBP,and in-hospital mortality were not significantly different between the groups.The primary outcome did not differ between the Child-Pugh subgroups.Similar results were observed in the sensitivity analyses.CONCLUSION No significant benefit to antibiotic prophylaxis for esophageal variceal bleeding treated with EVL was detected in this study.Global reassessment of routine antibiotic prophylaxis is imperative.展开更多
倾向得分匹配-双重差分模型(PSM⁃DID)是政策评估及因果推断中最为流行的方法之一.但是在实际应用中,该方法面临着控制变量在处理组样本和控制组样本之间非平衡性的挑战.传统基于均值差异t检验的平衡性检验容易产生片面和误导性的结论,...倾向得分匹配-双重差分模型(PSM⁃DID)是政策评估及因果推断中最为流行的方法之一.但是在实际应用中,该方法面临着控制变量在处理组样本和控制组样本之间非平衡性的挑战.传统基于均值差异t检验的平衡性检验容易产生片面和误导性的结论,使得后续因果推断产生偏误.为克服上述问题,本文对传统的平衡性检验提出以下改进:一是推荐更全面的多维度的平衡性测度指标,便于在匹配后更严谨地比较处理组和控制组的平衡性;二是提出了适用于非平衡样本的新估计方法:倾向得分匹配-逆概率加权-双重差分(PSM⁃IPW⁃DID),该方法结合了倾向得分匹配(PSM)克服样本自选择内生性及对非平衡样本稳健的优势和逆概率加权(inverse probability weighting,IPW)利用全样本信息的长处,在不进一步删除样本的情况下得到一种更稳健的双重差分估计方法.数据模拟和应用实例显示,本文提出的新方法能更全面、客观地评价宏观、微观政策的作用,得到更为可信的因果推断.展开更多
目的探讨C反应蛋白/白蛋白比值(C-reactive protein to albumin ratio,CAR)与维持性血液透析(maintenance hemodialysis,MHD)患者出现心血管事件风险的相关性。方法选择2016年8月至2019年12月在广州医科大学附属第二医院血液净化中心进...目的探讨C反应蛋白/白蛋白比值(C-reactive protein to albumin ratio,CAR)与维持性血液透析(maintenance hemodialysis,MHD)患者出现心血管事件风险的相关性。方法选择2016年8月至2019年12月在广州医科大学附属第二医院血液净化中心进行治疗的MHD患者为研究对象,随访截止时间为2021年3月31日。收集符合研究纳入标准的患者的人口学资料、合并症、原发病因、规律透析治疗3个月后的生化指标及随访截止时间内心血管事件发生情况。采用Kaplan-Meier法估计MHD患者出现心血管事件的概率。基于广义倾向性得分加权(GPSW)的Cox比例风险回归模型评估CAR水平与MHD患者出现心血管事件风险的关联。结果共纳入符合标准的研究对象170例,其中64例患者出现心血管事件(占37.6%)。基于GPSW的Cox比例风险回归模型提示(HR_(CAR)=2.087,95%CI:1.085~4.015,P=0.028),说明MHD患者的CAR平均每增加一个单位,出现心血管事件的风险比为2.087。结论CAR与MHD患者的心血管事件风险存在显著的正相关关系,这将有助于临床工作者识别具有高心血管事件风险的MHD患者并及时干预。展开更多
目的基于双重稳健估计(Doubly robust,DR)方法估计非小细胞肺癌治疗过程对院内死亡的因果效应大小,为降低非小细胞肺癌院内死亡率提供参考依据。方法依据非小细胞肺癌治疗质量评价体系,计算治疗过程指标的使用率,以治疗过程质量均值得...目的基于双重稳健估计(Doubly robust,DR)方法估计非小细胞肺癌治疗过程对院内死亡的因果效应大小,为降低非小细胞肺癌院内死亡率提供参考依据。方法依据非小细胞肺癌治疗质量评价体系,计算治疗过程指标的使用率,以治疗过程质量均值得分为界限将患者划分为高质量组与低质量组。以院内死亡为结局指标,采用倾向性评分逆概率加权(Inverse probability of treatment weighting,IPTW)法校正的Kaplan-Meier法及Cox回归,分析治疗过程质量对非小细胞肺癌院内死亡的影响;结合DR估计治疗过程对院内死亡的因果效应大小。结果治疗过程指标使用率的中位数为66.88%,患者治疗过程质量得分为0.270±0.124,其中高质量组为0.358±0.069,低质量组为0.158±0.081。经过IPTW法加权后,患者基线特征标准化平均差(Standardized mean difference,SMD)减小;IPTW前后两组患者生存曲线间差异具有统计学意义(P<0.05),高质量组患者的预后优于低质量组患者(IPTW前:HR=0.367,95%CI:0.275~0.491;IPTW后:HR=0.228,95%CI:0.167~0.312)。与低质量组相比,高质量组患者治疗过程对院内死亡的平均因果效应大小为-0.026。结论DR可弥补logistic或IPTW的不足,规避模型出错的风险,可以获得治疗过程质量对院内死亡的因果效应。医疗实践中应提高治疗过程指标的使用率,从而改善患者预后;因果效应研究提示,除治疗过程外,影响院内死亡的其他因素也是不可忽略的。展开更多
用户搜索时产生的点击数据分布,在不同的搜索场景下存在较大差异.现有算法如融合上下文的位置模型(contextual position based model,CPBM)往往只通过单个模型预测多种场景下的位置倾向性得分,不可避免地降低了模型在不同场景下的预测...用户搜索时产生的点击数据分布,在不同的搜索场景下存在较大差异.现有算法如融合上下文的位置模型(contextual position based model,CPBM)往往只通过单个模型预测多种场景下的位置倾向性得分,不可避免地降低了模型在不同场景下的预测准确性,影响去除位置偏置的效果.基于上述问题提出一种基于多任务学习的多门专家混合位置倾向性得分预测模型(multi-gate contextual position based model,MCPBM),在CPBM模型的基础上加入信息筛选结构,解决了多场景数据联合训练时预测准确性不佳的问题.同时,为了缓解不同任务收敛速度不一致的问题,提出了指数加权平均权重动态调整算法,在加速模型训练的同时提升了模型整体预测性能.实验结果表明提出的MCPBM模型在多场景数据联合训练时,预测准确性优于传统的CPBM;在使用MCPBM模型去除位置偏置后,基于生成的无偏数据训练得到的排序模型,在AvgRank排序指标上有1%~5%的提升.展开更多
基金Supported by the National Project for Clinical Key Specialty Development.
文摘BACKGROUND The benefit of adjuvant chemotherapy(ACT)for patients with no evidence of disease after pulmonary metastasis resection(PM)from colorectal cancer(CRC)remains controversial.AIM To assess the efficacy of ACT in patients after PM resection for CRC.METHODS This study included 96 patients who underwent pulmonary metastasectomy for CRC at a single institution between April 2008 and July 2023.The primary end-point was overall survival(OS);secondary endpoints included cancer-specific survival(CSS)and disease-free survival(DFS).An inverse probability of treat-ment-weighting(IPTW)analysis was conducted to address indication bias.Sur-vival outcomes compared using Kaplan-Meier curves,log-rank test,Cox regre-ssion and confirmed by propensity score-matching(PSM).RESULTS With a median follow-up of 27.5 months(range,18.3-50.4 months),the 5-year OS,CSS and DFS were 72.0%,74.4%and 51.3%,respectively.ACT had no significant effect on OS after PM resection from CRC[original cohort:P=0.08;IPTW:P=0.15].No differences were observed for CSS(P=0.12)and DFS(P=0.68)between the ACT and non-ACT groups.Multivariate analysis showed no association of ACT with better survival,while sublobar resection(HR=0.45;95%CI:0.20-1.00,P=0.049)and longer disease-free interval(HR=0.45;95%CI:0.20-0.98,P=0.044)were associated with improved survival.CONCLUSION ACT does not improve survival after PM resection for CRC.Further well-designed randomized controlled trials are needed to determine the optimal ACT regimen and duration.
基金approved by the Institutional Review Board of the Future Medical Research Centre Ethical Committee(Approval No.TGE02100-02).
文摘BACKGROUND Esophageal variceal bleeding is a severe complication associated with liver cirrhosis and typically necessitates endoscopic hemostasis.The current standard treatment is endoscopic variceal ligation(EVL),and Western guidelines recom-mend antibiotic prophylaxis following hemostasis.However,given the impro-vements in prognosis for variceal bleeding due to advancements in the management of bleeding and treatments of liver cirrhosis and the global concerns regarding the emergence of multidrug-resistant bacteria,there is a need to reassess the use of routine antibiotic prophylaxis after hemostasis.AIM To evaluate the effectiveness of antibiotic prophylaxis in patients treated for EVL.METHODS We conducted a 13-year observational study using the Tokushukai medical database across 46 hospitals.Patients were divided into the prophylaxis group(received antibiotics on admission or the next day)and the non-prophylaxis group(did not receive antibiotics within one day of admission).The primary outcome was composed of 6-wk mortality,4-wk rebleeding,and 4-wk spontaneous bacterial peritonitis(SBP).The secondary outcomes were each individual result and in-hospital mortality.A logistic regression with inverse probability of treatment weighting was used.A subgroup analysis was conducted based on the Child-Pugh classification to determine its influence on the primary outcome measures,while sensitivity analyses for antibiotic type and duration were also performed.RESULTS Among 980 patients,790 were included(prophylaxis:232,non-prophylaxis:558).Most patients were males under the age of 65 years with a median Child-Pugh score of 8.The composite primary outcomes occurred in 11.2%of patients in the prophylaxis group and 9.5%in the non-prophylaxis group.No significant differences in outcomes were observed between the groups(adjusted odds ratio,1.11;95%confidence interval,0.61-1.99;P=0.74).Individual outcomes such as 6-wk mortality,4-wk rebleeding,4-wk onset of SBP,and in-hospital mortality were not significantly different between the groups.The primary outcome did not differ between the Child-Pugh subgroups.Similar results were observed in the sensitivity analyses.CONCLUSION No significant benefit to antibiotic prophylaxis for esophageal variceal bleeding treated with EVL was detected in this study.Global reassessment of routine antibiotic prophylaxis is imperative.
文摘倾向得分匹配-双重差分模型(PSM⁃DID)是政策评估及因果推断中最为流行的方法之一.但是在实际应用中,该方法面临着控制变量在处理组样本和控制组样本之间非平衡性的挑战.传统基于均值差异t检验的平衡性检验容易产生片面和误导性的结论,使得后续因果推断产生偏误.为克服上述问题,本文对传统的平衡性检验提出以下改进:一是推荐更全面的多维度的平衡性测度指标,便于在匹配后更严谨地比较处理组和控制组的平衡性;二是提出了适用于非平衡样本的新估计方法:倾向得分匹配-逆概率加权-双重差分(PSM⁃IPW⁃DID),该方法结合了倾向得分匹配(PSM)克服样本自选择内生性及对非平衡样本稳健的优势和逆概率加权(inverse probability weighting,IPW)利用全样本信息的长处,在不进一步删除样本的情况下得到一种更稳健的双重差分估计方法.数据模拟和应用实例显示,本文提出的新方法能更全面、客观地评价宏观、微观政策的作用,得到更为可信的因果推断.
文摘目的探讨C反应蛋白/白蛋白比值(C-reactive protein to albumin ratio,CAR)与维持性血液透析(maintenance hemodialysis,MHD)患者出现心血管事件风险的相关性。方法选择2016年8月至2019年12月在广州医科大学附属第二医院血液净化中心进行治疗的MHD患者为研究对象,随访截止时间为2021年3月31日。收集符合研究纳入标准的患者的人口学资料、合并症、原发病因、规律透析治疗3个月后的生化指标及随访截止时间内心血管事件发生情况。采用Kaplan-Meier法估计MHD患者出现心血管事件的概率。基于广义倾向性得分加权(GPSW)的Cox比例风险回归模型评估CAR水平与MHD患者出现心血管事件风险的关联。结果共纳入符合标准的研究对象170例,其中64例患者出现心血管事件(占37.6%)。基于GPSW的Cox比例风险回归模型提示(HR_(CAR)=2.087,95%CI:1.085~4.015,P=0.028),说明MHD患者的CAR平均每增加一个单位,出现心血管事件的风险比为2.087。结论CAR与MHD患者的心血管事件风险存在显著的正相关关系,这将有助于临床工作者识别具有高心血管事件风险的MHD患者并及时干预。
文摘目的基于双重稳健估计(Doubly robust,DR)方法估计非小细胞肺癌治疗过程对院内死亡的因果效应大小,为降低非小细胞肺癌院内死亡率提供参考依据。方法依据非小细胞肺癌治疗质量评价体系,计算治疗过程指标的使用率,以治疗过程质量均值得分为界限将患者划分为高质量组与低质量组。以院内死亡为结局指标,采用倾向性评分逆概率加权(Inverse probability of treatment weighting,IPTW)法校正的Kaplan-Meier法及Cox回归,分析治疗过程质量对非小细胞肺癌院内死亡的影响;结合DR估计治疗过程对院内死亡的因果效应大小。结果治疗过程指标使用率的中位数为66.88%,患者治疗过程质量得分为0.270±0.124,其中高质量组为0.358±0.069,低质量组为0.158±0.081。经过IPTW法加权后,患者基线特征标准化平均差(Standardized mean difference,SMD)减小;IPTW前后两组患者生存曲线间差异具有统计学意义(P<0.05),高质量组患者的预后优于低质量组患者(IPTW前:HR=0.367,95%CI:0.275~0.491;IPTW后:HR=0.228,95%CI:0.167~0.312)。与低质量组相比,高质量组患者治疗过程对院内死亡的平均因果效应大小为-0.026。结论DR可弥补logistic或IPTW的不足,规避模型出错的风险,可以获得治疗过程质量对院内死亡的因果效应。医疗实践中应提高治疗过程指标的使用率,从而改善患者预后;因果效应研究提示,除治疗过程外,影响院内死亡的其他因素也是不可忽略的。
文摘用户搜索时产生的点击数据分布,在不同的搜索场景下存在较大差异.现有算法如融合上下文的位置模型(contextual position based model,CPBM)往往只通过单个模型预测多种场景下的位置倾向性得分,不可避免地降低了模型在不同场景下的预测准确性,影响去除位置偏置的效果.基于上述问题提出一种基于多任务学习的多门专家混合位置倾向性得分预测模型(multi-gate contextual position based model,MCPBM),在CPBM模型的基础上加入信息筛选结构,解决了多场景数据联合训练时预测准确性不佳的问题.同时,为了缓解不同任务收敛速度不一致的问题,提出了指数加权平均权重动态调整算法,在加速模型训练的同时提升了模型整体预测性能.实验结果表明提出的MCPBM模型在多场景数据联合训练时,预测准确性优于传统的CPBM;在使用MCPBM模型去除位置偏置后,基于生成的无偏数据训练得到的排序模型,在AvgRank排序指标上有1%~5%的提升.
