Constrained empirical-likelihood confidence regions in nonignorable covariate-missing data problems

Missing covariates in regression analysis are a pervasive problem in medical, social, and economic researches. We study empirical-likelihood confidence regions for unconstrained and constrained regression parameters in a nonignorable covariate-missing data problem. For an assumed conditional mean regression model, we assume that some covariates are fully observed but other covariates are missing for some subjects. By exploitation of a probability model of missingness and a working conditional score model from a semiparametric perspective, we build a system of unbiased estimating equations, where the number of equations exceeds the number of unknown parameters. Based on the proposed estimating equations, we introduce unconstrained and constrained empirical-likelihood ratio statistics to construct empirical-likelihood confidence regions for the underlying regression parameters without and with constraints. We establish the asymptotic distributions of the proposed empirical-likelihood ratio statistics. Simulation results show that the proposed empirical-likelihood methods have a better finite-sample performance than other competitors in terms of coverage probability and interval length. Finally, we apply the proposed empirical-likelihood methods to the analysis of a data set from the US National Health and Nutrition Examination Survey.     

Relationship between rosacea and dietary factors: A multicenter retrospective case–control survey

Although patients with rosacea often consult dermatologists for dietary factors that might be related to their skin disorders, few studies have been conducted to research the relationship between rosacea and dietary factors. The purpose of this study was to evaluate the potential relationship between rosacea and diet among the large Chinese population with rosacea, which would provide dietary guidelines for patients with rosacea. A multicenter case–control study was conducted. The feeding frequency 2 years before the occurrence of rosacea was collected by standardized questionnaires. Multiple logistic regression analysis was used to calculate risks related to the diet. One thousand three hundred and forty‐seven patients with rosacea and 1290 controls were enrolled in our study. We found that high‐frequency intake of fatty food and tea presented a positive correlation with rosacea, while high‐frequency dairy product intake showed significant negative correlation with rosacea. Sweet food, coffee and spicy food appeared to be independent of any subset of rosacea in our study. However, high‐frequency dairy product intake showed a borderline beneficial effect on rosacea severity. We further analyzed the correlation between diet and the subtype of rosacea. We found that high‐frequency fatty intake was associated with erythematotelangiectatic rosacea (ETR) and phymatous rosacea, while high‐frequency tea intake was only associated with ETR. In addition, high‐frequency dairy product intake showed negative correlations with ETR and papulopustular rosacea. Rosacea is associated with some dietary factors, and our study is valuable in establishing dietary guidelines to prevent and improve rosacea.     

不同切口白内障联合青光眼手术对眼表的影响

目的：探讨单切口和双切口白内障超声乳化联合小梁切除术治疗闭角型青光眼合并年龄相关性白内障术后眼表的影响。

方法：随机抽取在我院行单切口和双切口白内障超声乳化吸除、人工晶状体植入联合小梁切除术患者各26例26眼，对临床资料进行回顾性分析。比较两组病例术前1d和术后1wk，1、3mo时的泪膜破裂时间(break up time，BUT)，泪液分泌试验Ⅰ(SchirmerⅠ time，SⅠt)，角膜荧光素染色程度(corneal fluorescein staining，FL)等，并对结果进行统计学分析。

结果：所有入选的病例均在局部麻醉下行手术治疗，术后随访3mo。两组患者术后1wk，1mo的BUT，FL，SⅠt指标数值与术前相比均有明显差异(P<0.01)，术后3mo基本恢复术前水平。术后1wk，1mo双切口组BUT，SⅠt均明显短于单切口组(P<0.05)； FL双切口组术后1wk明显高于单切口组(P<0.05)，而术后1mo两组差异无统计学意义(P>0.05)。术后3mo，两组患者的BUT，FL，SⅠt相比差异均无统计学意义(P>0.05)。

结论：单切口和双切口的白内障超声乳化联合显微小梁切除术术后均对术眼眼表有影响，双切口组影响更大，且相关指标异常的高峰期出现在术后1mo之内。     

手术室医辅人员任务智能分配的抢单模式管理

目的研发适用于手术室医辅人员任务分配管理的智能软件信息系统,并探讨其运行效果。方法将2018年3月试运行抢单信息系统的509台次手术设为实验组,对医辅人员运用抢单模式进行管理;对同期未实施的486台次同类手术设为对照组,运用常规管理模式;比较两组的运行效果。结果实验组应答时间和完成任务时间显著短于对照组,护士满意率显著提升(均P0.01)。结论抢单信息系统精准记录了医辅人员的工作量和时间节点,提高了工作效率和护理人员满意率,促进了后勤医辅人员的科学化、精细化管理。     

The Chinese National Twin Registry: a ‘gold mine’ for scientific research

The Chinese National Twin Registry (CNTR) currently includes data from 61 566 twin pair from 11 provinces or cities in China. Of these, 31 705, 15 060 and 13 531 pairs are monozygotic, same‐sex dizygotic and opposite‐sex dizygotic pairs, respectively, determined by opposite sex or intrapair similarity. Since its establishment in 2001, the CNTR has provided an important resource for analysing genetic and environmental influences on chronic diseases especially cardiovascular diseases. Recently, the CNTR has focused on collecting biologic specimens from disease‐concordant or disease‐discordant twin pairs or from twin pairs reared apart. More than 8000 pairs of these twins have been registered, and blood samples have been collected from more than 1500 pairs. In this review, we summarize the main findings from univariate and multivariate genetic effects analyses, gene–environment interaction studies, omics studies exploring DNA methylation and metabolomic markers associated with phenotypes. There remains further scope for CNTR research and data mining. The plan for future development of the CNTR is described. The CNTR welcomes worldwide collaboration.     

Ticagrelor Versus Clopidogrel in Patients With STEMI Treated With Fibrinolysis: TREAT Trial

BackgroundThe efficacy of ticagrelor in the long-term post–ST-segment elevation myocardial infarction (STEMI) treated with fibrinolytic therapy remains uncertain.ObjectivesThe purpose of this study was to evaluate the efficacy of ticagrelor when compared with clopidogrel in STEMI patients treated with fibrinolytic therapy.MethodsThis international, multicenter, randomized, open-label with blinded endpoint adjudication trial enrolled 3,799 patients (age <75 years) with STEMI receiving fibrinolytic therapy. Patients were randomized to ticagrelor (180-mg loading dose, 90 mg twice daily thereafter) or clopidogrel (300- to 600-mg loading dose, 75 mg daily thereafter). The key outcomes were cardiovascular mortality, myocardial infarction, or stroke, and the same composite outcome with the addition of severe recurrent ischemia, transient ischemic attack, or other arterial thrombotic events at 12 months.ResultsThe combined outcome of cardiovascular mortality, myocardial infarction, or stroke occurred in 129 of 1,913 patients (6.7%) receiving ticagrelor and in 137 of 1,886 patients (7.3%) receiving clopidogrel (hazard ratio: 0.93; 95% confidence interval: 0.73 to 1.18; p = 0.53). The composite of cardiovascular mortality, myocardial infarction, stroke, severe recurrent ischemia, transient ischemic attack, or other arterial thrombotic events occurred in 153 of 1,913 patients (8.0%) treated with ticagrelor and in 171 of 1,886 patients (9.1%) receiving clopidogrel (hazard ratio: 0.88; 95% confidence interval: 0.71 to 1.09; p = 0.25). The rates of major, fatal, and intracranial bleeding were similar between the ticagrelor and clopidogrel groups.ConclusionAmong patients age <75 years with STEMI, administration of ticagrelor after fibrinolytic therapy did not significantly reduce the frequency of cardiovascular events when compared with clopidogrel. (Ticagrelor in Patients With ST Elevation Myocardial Infarction Treated With Pharmacological Thrombolysis [TREAT]; NCT02298088)