Perioperative adverse cardiac events and mortality after non-cardiac surgery: a multicenter study

Choi Byungjin,Oh Ah Ran,박정찬,이종환,Yang Kwangmo,Lee Dong Yun,Rhee Sang Youl,Kang Sang Soo,Lee Seung Do,Lee Sun Hack,Jeong Chang Won,Park Bumhee,설수빈,Park Rae Woong,Lee Seunghwa 대한마취통증의학회 2024 Korean Journal of Anesthesiology Vol.77 No.1

Background: Perioperative adverse cardiac events (PACE), a composite of myocardial infarction, coronary revascularization, congestive heart failure, arrhythmic attack, acute pulmonary embolism, cardiac arrest, and stroke during 30-day postoperative period, is associated with long-term mortality, but with limited clinical evidence. We compared long-term mortality with PACE using data from nationwide multicenter electronic health records.Methods: Data from 7 hospitals, converted to Observational Medical Outcomes Partnership Common Data Model, were used. We extracted records of 277,787 adult patients over 18 years old undergoing non-cardiac surgery for the first time at the hospital and had medical records for more than 180 days before surgery. We performed propensity score matching and then an aggregated meta‑analysis.Results: After 1:4 propensity score matching, 7,970 patients with PACE and 28,807 patients without PACE were matched. The meta‑analysis showed that PACE was associated with higher one-year mortality risk (hazard ratio [HR]: 1.33, 95% CI [1.10, 1.60], P = 0.005) and higher three-year mortality (HR: 1.18, 95% CI [1.01, 1.38], P = 0.038). In subgroup analysis, the risk of one-year mortality by PACE became greater with higher-risk surgical procedures (HR: 1.20, 95% CI [1.04, 1.39], P = 0.020 for low-risk surgery; HR: 1.69, 95% CI [1.45, 1.96], P < 0.001 for intermediate-risk; and HR: 2.38, 95% CI [1.47, 3.86], P = 0.034 for high-risk).Conclusions: A nationwide multicenter study showed that PACE was significantly associated with increased one-year mortality. This association was stronger in high-risk surgery, older, male, and chronic kidney disease subgroups. Further studies to improve mortality associated with PACE are needed.

A Test for Neutrality of Composition Using the Box-Cox Multiplicative Transformation

Byungjin Choi 고려대학교 통계연구소 2002 應用統計 Vol.17 No.-

Maximum Likelihood Estimation of Parameters from a Multivariate Normal Sample with 2-step Monotone Missing Pattern

Byungjin Choi 고려대학교 통계연구소 2004 應用統計 Vol.19 No.-

A sample with special missing pattern called a monotone sample or a monotone missing data pattern occurs in many applications. The statistical methods for analyzing a monotone sample have been developed by several analysts. The purpose of this paper is to introduce the maximum likelihood estimation of parameters when there is a multivariate normal sample with 2-step monotone pattern, and to present the maximum likelihood estimates of parameters in closed forms. These estimates can be obtained by maximizing the overall likelihood function which is expressed in terms of the marginal and conditional likelihood functions with respect to parameters. The maximum likelihood estimates presented are expected to he used to develop statistical methods for analyzing a multivariate normal sample with 2-step monotone pattern in applications.

Estimation for scale parameter of type-I extreme value distribution

Choi, Byungjin The Korean Data and Information Science Society 2015 한국데이터정보과학회지 Vol.26 No.2

In a various range of applications including hydrology, the type-I extreme value distribution has been extensively used as a probabilistic model for analyzing extreme events. In this paper, we introduce methods for estimating the scale parameter of the type-I extreme value distribution. A simulation study is performed to compare the estimators in terms of mean-squared error and bias, and the obtained results are provided.

A Test for Neutrality of Composition Using the Box-Cox Multiplicative Transformation

Choi, Byungjin 高麗大學校統計硏究所 2002 應用統計 Vol.17 No.-

In this paper, we propose a Box-Cox multiplicative transformation to model neutrality of composition at fixed level. The properties of the transformation are given and the likelihood ratio test for neutrality using the transformation is derived. The numerical illustration is provided to compare the results to Aitchison's case.

Power Investigation of the Entropy-Based Test of Fit for Inverse Gaussian Distribution by the Information Discrimination Index

Choi, Byungjin 한국통계학회 2012 Communications for statistical applications and me Vol.19 No.6

Inverse Gaussian distribution is widely used in applications to analyze and model right-skewed data. To assess the appropriateness of the distribution prior to data analysis, Mudholkar and Tian (2002) proposed an entropy-based test of fit. The test is based on the entropy power fraction(EPF) index suggested by Gokhale (1983). The simulation results report that the power of the entropy-based test is superior compared to other goodness-of-fit tests; however, this observation is based on the small-scale simulation results on the standard exponential, Weibull W(1; 2) and lognormal LN(0:5; 1) distributions. A large-scale simulation should be performed against various alternative distributions to evaluate the power of the entropy-based test; however, the use of a theoretical method is more effective to investigate the powers. In this paper, utilizing the information discrimination(ID) index defined by Ehsan et al. (1995) as a mathematical tool, we scrutinize the power of the entropy-based test. The selected alternative distributions are the gamma, Weibull and lognormal distributions, which are widely used in data analysis as an alternative to inverse Gaussian distribution. The study results are provided and an illustrative example is analyzed.

극단값분포에 대한 적합도 검정에 관한 연구

최병진(Byungjin Choi) 한국데이터정보과학회 2019 한국데이터정보과학회지 Vol.30 No.3

극단값분포는 수명검정과 수문학 등의 다양한 영역에서 데이터 분석을 위한 확률모형으로 광범위하게 시용되고 있다. 극단값분포가 이들 영역에서 이론적 또는 응용적인 면에서 매력적인 모형이라고 하더라도 분석모형으로 데이터에 적합한지를 검증해 볼 필요가 있다. 본 논문에서는 모수들이 미지인 극단값분포에 대한 적합도 검정을 위해 앤더슨-달링 (Anderson-Darling)과 크래머-미제스 (Cramervon Mises) 검정의 사용을 논의한다. 검정에 사용할 검정통계량은 극단값분포와 관련된 모수를 포함하게 되고 이것을 편의-수정 최대가능도추정량과 최대엔트로피추정량 등으로 대체한 수정된 검정통계량들을 제시한다. 검정의 수행을 위해 필요한 기각값은 모의실험을 통해 추정하여 표의 형태로 제공한다. 또한 검정력 비교를 위해 모의실험을 실시하고 그 결과를 제시한다. The extreme value distribution is extensively used as a probability model for data analysis in various fields including life testing and hydrology. Although the use of the extreme value distribution is theoretically or practically justified in such fields, it is necessary to ascertain the appropriateness of the distribution prior to data analysis. In this paper, we discuss the use of the modified Anderson-Darling and Cramer-von Mises tests of fit for the extreme value distribution with unknown parameters. Since the test statistics to be used include the parameters involved in the extreme value distribution, we present the modified test statistics by replacing the unknown parameters with the estimators obtained by the maximum likelihood method for reducing bias and the maximum entropy method, etc. The critical values of the proposed tests using the modified test statistics are estimated by Monte-Carlo simulations and provided in a tabular form. We also carry out Monte-Carlo simulations for performance comparison in terms of power and present the obtained results.

에너지산업에서 겨울철 NH3 누출 사고 시 사업장 외부의 피해범위에 관한 연구

최병진(Choi Byungjin) 한국정보과학회 2018 한국정보과학회 학술발표논문집 Vol.2018 No.6

도시환경의 미소공간 대기분산시스템에 관한 연구

최병진(Choi Byungjin) 한국정보과학회 2017 한국정보과학회 학술발표논문집 Vol.2017 No.06

가에타노 줌보의 해부학 밀랍 모형

최병진(Choi, Byungjin) 서양미술사학회 2017 서양미술사학회논문집 Vol.47 No.-

본 논문은 역사적으로 발전해온 의학과 미술의 협업 관계를 고려해서 라 스페콜라 자연사 박물관에서 소장하고 있는 가에타노 줌보의 4점의 소극장과 〈두상의 해부학〉을 재조명한다. 특히 〈두상의 해부학〉은 의학사 분야에서 높이 평가받아왔지만 미술사 분야에서는 많이 연구되지 않았다. 따라서 최초의 다색 해부학 밀랍 모형으로서 접근하는 대신 문화적 의미를 담고 있는 미술품으로서 접근했다. 이를 위해 〈두상의 해부학〉과 같은 시기에 제작된 4점의 소극장은 죽음에 대한 줌보의 생각을 보여준다. 〈두상의 해부학〉은 소극장을 작업한 후 볼로냐에서 인체를 재현한 과학적 지식을 접한 후 제작된 것으로 추정된다. 따라서 소극장 그룹과 〈두상의 해부학〉이 연결고리가 있다고 판단했다. 이 과정에서 소극장 그룹과 연결될 수 있는 부분은 〈두상의 해부학〉의 표정이었다. 〈두상의 해부학〉은 해부학 밀랍 모형이라는 점에서 다시점이 적용된 내부 구조가 중요했다. 반면 작품에서 표피를 구성하는 인물의 표정이 지식의 전달에 반드시 필요한 부분이 아니었기 때문이다. 이를 분석하는 과정에서 동시대의 작품들이나 이후 해부학 모델에서 지속적으로 발견되는 명확하지 않은 감정 표현이 담긴 이 표정은 르네상스 시대 가우리코 이후의 평론에서 설명하는 ‘모호성’과 서사 구조의 특징이 담겨있으며 이는 바로크 시대의 극화된 서사 구조의 특성과도 잘 부합한다는 점에 주목했다. 이를 토대로 동시대 가톨릭 종교개혁의 신학과 이미지에 대한 관점이나 죽음이라는 테마와 연관된 아졸리니와 같이 밀랍을 활용해서 제작한 종교적 봉헌물을 비교해본다면 <두상의 해부학>이 죽음과 연옥의 의미를 환기하는 문화적 혼유라는 사실을 보여준다. 그리고 이 연구는 의학과 미술 두 분야가 상호 융합된다기보다 상호 관점의 차용과 교환 속에서 각 분야를 발전시키면서 인간에 대한 의미체계를 함께 구성해나간다는 점을 보여주었다. This paper examines and analyzes the Anatomical Head of Gaetano Zumbo, the earliest known multi-colored anatomical wax model, in relation to his four teatrini – Vanitas of Great Human Being, Pestilence, Consequence of Syphilis, and Sepulchre – all of which are now on display in the Museum of Natural History of Florence, also called La Specola. Aside from being a rigorous anatomical model, the Anatomical Head may be viewed as a distinctive work of art exhibiting many of significant cultural characteristics of the period. Its facial expression, which is not an essential element of anatomical model, adds an artistic dimension which calls for some imaginative interpretations. It is posited that the Head’s facial expression is marked by certain ambiguities and epic styles that match the dramatic traits of Baroque art. It is also shown that the Head embodies the motif of death and the image of purgatory in reflection of the contemporary debates put forward by the Reformation and the Counter-Reformation movements. The Anatomical Head of Zumbo demonstrates how the two disparate fields of art and medicine could collaborate through the sharing of their respective perspectives so as to advance the system of knowledge concerning human beings and the culture.