• Journal of the Korean Data and Information Science Society
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• v.26 no.6
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• pp.1317-1325
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• 2015

There are two types of clinical research to figure out risk factor for disease using collected data. One is prospective study to approach the subjects from the present time and the other is retrospective study to find the risk factor using the subject's information in the past. Both approached and study design are different but the purpose of the two studies is to identify a significant difference between two groups and to find out what the variables to influence groups. Especially when comparing the two groups in clinical research, we have to look at the difference between the impact clinical variables by group while controlling the influence of the baseline characteristics variables such as age and sex. However, in the retrospective study, the difference of baseline characteristic variables can occur more frequently because the past records did not randomly assign subjects into two groups. In clinical data analysis use covariates to solve this problem. Typically, the analysis method using the analysis of covariance of variance, adjusted model, and propensity score matching method. This study is introduce the way of equality adjustment between groups data analysis using covariates in retrospective clinical studies and apply it to the recurrence of gastric cancer data.

• Investigative Magnetic Resonance Imaging
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• v.2 no.1
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• pp.1-13
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• 1998

MR 영상을 획득하기 위해서 사용하고 있는 가장 기본적인 펄스파형(pulse sequense)은 스핀반향(spin echo)과 경사자계반향(gradient echo)이며, 최근 다방면으로 응용되고 있는 고속영상기법들은 이 두가지 펄스파형을 기보능로 하고 있다. 펄스파형의 종류와 펄스파형의 변수(TR, TE TI등의 펄스 상이의 시간 간격 및 flip angle 등)에 따라서 MR영상의 특징(대조도, SNR, artifact 등)이 달라지므로 임상응용시에는 목적에 따라 적절한 펄스파혀의 선택과 함께 변수값을 결정해야 한다. 이를 위하여 펄스파형에 관한 기본적인 지식과 함게 간단한 임상응용에 관하여 기술하고자 한다.

• Physical Therapy Korea
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• v.7 no.4
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• pp.1-7
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• 2000

이 연구의 목적은 만성요통 여성 환자들에서 나타나는 자세 이상을 평가하고 방사선적 변수들과 임상적인 변수들과의 상관성을 알아보는 것이다. 이 연구의 대상자는 만성요통 여성 환자 38명과 대조군 32명이었다. 변수의 측정은 모든 대상자들이 이완된 자세로 기립한 상태에서 방사선 검사를 실시한 후 경추전만각, 흉추후만각, 요추전만각, 그리고 요추경사각을 측정하였다. 대상자들의 연령과 통증기간은 의무기록지를 참고하였다. 자료분석은 요통군과 대조군의 방사선적 변수들 간의 유의한 차이가 있는지를 알아보기 위해 독립된 t-검정을 시행하였고, 방사선적 변수들과 임상적 변수들과의 상관성을 알아보기 위해 피어슨 상관분석을 시행하였다. 연구결과 만성요통 환자군과 대조군사이의 경추전만각(p<.05), 요추전만각(p<.001), 그리고 천추경사각(p<.01)에서 통계학적으로 유의한 차이가 보였다. 통증기간은 요추전만각과 통계적학으로 유의한 상관관계가 있었으며(p<.05), 경추전만각은 흉추후만각과 통계학적으로 유의한 상관관계가 있었다(p<.05). 또한 흉추후만각, 요추전만각, 그리고 천추경사각은 각각 상호간에 상관관계가 있었다(p<.05). 만성요통은 요추만곡의 변화를 초래하여 흉추부 및 경추부의 자세이상을 유발할 수 있다. 그러므로 요통으로 인하여 올 수 있는 신체 전반적인 자세이상을 미리 예측하고 이를 교정하여야만 장기적으로 올 수 있는 합병증들을 예방할 수 있을 것이다.

• Journal of the Korean Data and Information Science Society
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• v.23 no.4
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• pp.677-682
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• 2012

There are lots of sampling design which is determined for sample survey in various fields. Especially, it is important problem for clinical data because basic characteristic variables by group which consist of experiment group and control group in population should be reflect to sample. Therefore, frequencies, center scales and dispersion scales of variables by group in population should be similar in sample. But usual sampling design is very complicate so it is difficult to use in practice for researcher. In this paper, we consider the sampling method using simulation. We applied the proposed method to colon cancer data from a hospital. We compare basic characteristic variables between population and sample with mean, frequency and statistic hypothesis test.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.3
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• pp.296-303
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• 2020

This study examined the factors affecting the emergency nursing performance of nursing students during a simulation. The variables related to the simulation were the objective and subjective emergency nursing performance, critical thinking, program outcome, simulation satisfaction, simulation confidence, and simulation immersion. The participants were 92 senior students who provided informed consent with an explanation about attending the study. The general characteristics and simulation-related data were obtained from the students before and after the simulation. An assessor evaluated the objective emergency nursing performance during the simulation and program outcome through a report reviewed after the simulation. Data analysis was performed using the number, percentage, mean, standard deviation, X²-test, one-way ANOVA, Pearson correlation, and progressive regression through the SPSS/WIN 22.0 program. Emergency nursing performance by the assessor was negatively associated with the satisfaction of clinical practice (r=-.31, p=.005) and positively related to the subjective clinical performance (r=.23, p=.036). The affecting rate was just 12%, which was low for explaining the objective emergency nursing performance during the simulation. Further studies will be needed to explore other factors affecting the emergency nursing performance.

• Clinics in Shoulder and Elbow
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• v.16 no.1
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• pp.63-72
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• 2013

In medical research, multivariate analysis, especially multiple regression analysis, is used to analyze the influence of multiple variables on the result. Multiple regression analysis should include variables in the model and the problem of multi-collinearity as there are many variables as well as the basic assumption of regression analysis. The multiple regression model is expressed as the coefficient of determination, $R^2$ and the influence of independent variables on result as a regression coefficient, ${\beta}$. Multiple regression analysis can be divided into multiple linear regression analysis, multiple logistic regression analysis, and Cox regression analysis according to the type of dependent variables (continuous variable, categorical variable (binary logit), and state variable, respectively), and the influence of variables on the result is evaluated by regression coefficient${\beta}$, odds ratio, and hazard ratio, respectively. The knowledge of multivariate analysis enables clinicians to analyze the result accurately and to design the further research efficiently.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.12
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• pp.660-671
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• 2020

This study is a descriptive survey study that attempted to confirm clinical nurses' consciousness of biomedical ethics, moral sensitivity, critical thinking deposition, and nursing ethics code of clinical nurses, as well as to identify the factors influencing the recognition of the nursing code of ethics. The general and ethical characteristics of the subject were calculated by frequency, percentage, mean, and standard deviation, and the difference for each variable according to the general and ethical characteristics was analyzed using SAS 9.4, independent t-test, and one-way ANOVA, and Scheffé test. The average, standard deviation, and the minimum and maximum values were used for the scores of each variable, and the correlation was determined using the Pearson correlation coefficient. Multiple regression was used to identify the factors that influence the recognition of the nurse's code of ethics. All variables showed significant correlations. Critical thinking deposition (p<.05) was the most influential variable in recognizing the code of ethics for nurses. Critical thinking deposition (p<.001), consciousness in biomedical ethics (p<.001), and moral sensitivity (p<.001) were shown to be affected in order, with 27.4% explaining power. Therefore, it is necessary to develop and apply educational programs to clinical nurses that can improve critical thinking, life and bioethics, and moral sensitivity.

• The Journal of the Korean dental association
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• v.37 no.3 s.358
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• pp.181-187
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• 1999

치주질환은 초기에는 환자 자신이 전혀 모르는 가운데 진행되어 환자가 증상을 느낄 때 쯤되면 이미 병변이 상당히 진행된 상태가 되어 치료하기 어려운 경우가 많게 되므로 치주질환의 원인과 질병상태를 조기에 파악하여 치료하는 것이 중요하다. 치주질환을 진단하는데 있어서는 객관적인 임상적 기준을 필요로 하게되며 치주질환의 활성도를 알아보기위해서는 여러 임상적 변수가 동시에 필요하므로 우선 환자의 병력을 파악하고 구강의 및 구강내 검사를 완전히 시행한 후 환자의 치아의 치주조직상태를 검사하게 된다. 이 장에서는치주질환의 진단에 필수적인 요인인 치아와 치주조직 검사에 대하여 중점적으로 애기 하고자 한다.

• The Korean Journal of Applied Statistics
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• v.22 no.2
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• pp.341-353
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• 2009

We consider sample-size determination problem motivated by comparative clinical trials where patient outcomes are characterized by a bivariate outcome of efficacy and safety. Thall and Cheng (1999) presented a sample size methodology for the case of bivariate binary outcomes. We propose a bivariate Wilcoxon-Mann-Whitney(WMW) statistics for sample-size determination for binary outcomes, and this nonparametric method can be equally used to determine sample sizes of ordinal outcomes. The two methods of sample size determination rely on the same testing strategy for the target parameters but differs in the test statistics, an asymptotic bivariate normal statistic of the transformed proportions in Thall and Cheng (1999) and nonparametric bivariate WMW statistic in the other method. Sample sizes are calculated for the two experimental oncology trials, described in Thall and Cheng (1999), and for the first trial example the sample sizes of a bivariate WMW statistic are smaller than those of Thall and Cheng (1999), while for the second trial example the reverse is true.

• Journal of the Korean Society of Radiology
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• v.14 no.5
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• pp.705-713
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• 2020

Arteriosclerosis is a disease in which blood circulation is impaired due to loss of elasticity as blood vessels become narrower, and is a potential cause of recently increasing cardiovascular and cerebrovascular diseases. Carotid ultrasound is used as a predictor of cardiovascular and cerebrovascular diseases by evaluating the degree of atherosclerosis. Therefore, this paper attempted to investigate the correlation between the increase in the thickness of the inner media and various clinical variables in carotid ultrasound. Patients with carotid ultrasound findings were classified into three stages: mild intima thickening, sclerosis, and significant stenosis. CAVI (Carotid Ankle Vascular Index: vascular age) data measured in the degree and physical characteristics of the carotid artery(gender, age, body mass index, blood pressure), blood test(total cholesterol, triglycerides, high-density lipoprotein, low-density lipoprotein, creatine phosphokinase, fasting blood sugar), and arteriosclerosis test were collected. It was confirmed that the carotid intima thickness was correlated with variables such as hypertension, hyperlipidemia, and BMI, and also correlated with the risk factors of cardiovascular disease as CAVI increased.