• 한국융합학회논문지
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• 제13권1호
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• pp.399-408
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• 2022

본 연구에서는 65세 이상 고령자를 대상으로 대사증후군 진단을 위한 지질비율 지표의 유용성을 비교하고자 하였다. 2018년 1월부터 2020년 12월까지 서울지역 종합병원에서 건강검진을 받은 65세 이상 1,464명을 대상으로 하였다. 혈액검사를 통해 혈장 동맥경화 지수를 포함한 지질비율 지표를 측정하였다. 지질비율 지표의 사분위수에 따른 대사증후군 유병률은 로지스틱 회귀분석으로 확인하였다. 또한 수신자 조작 특성(receiver operating characteristic, ROC) 곡선으로 지질비율 지표의 대사증후군 예측능력과 절단값을 추정하였다. 동맥경화 지수와 허리둘레의 상관성이 남녀 모두에서 가장 높았으며(r=0.278, p<0.001 vs r=0.252, p<0.001), 지질비율 지표는 1사분위수와 비교하여 4사분위수에서 대사증후군 발병률이 높았다. 혈장 동맥경화 지수는 다른 지질비율 지표보다 ROC 곡선 아래의 면적(area under the ROC curve; AUC)값이 남녀 각각 0.826(95% CI=0.799-0.850), 0.852(95% CI=0.820-0.881)로 가장 높게 나타났으며, 최적 절단값은 남녀 모두 0.44였다(p<0.001). 따라서 지질비율 지표 중 혈장 동맥경화 지수는 65세 이상 고령자의 대사증후군 진단에 가장 유용한 지표로 나타났다.

• 한국방사선학회논문지
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• 제16권5호
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• pp.661-672
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• 2022

COVID-19를 발생시키는 SARS-CoV2 바이러스가 발생한 후 전염병은 전 세계로 확산되며, 감염 사례와 사망자의 수가 빠르게 증가함에 따라 의료자원의 부족 문제가 야기되었다. 이것을 해결하려는 방법으로 인공지능을 활용한 흉부 X-ray 검사가 일차적인 진단 방법으로 관심을 받게 되었다. 본 연구에서는 인공지능을 통한 COVID-19 판독 방식들에 대해 종합적으로 분석하는 것에 목적을 두고 있다. 이 목적을 달성하기 위해 292개의 논문을 일련의 분류 방법을 거처 수집했다. 이러한 자료들을 토대로 Accuracy, Precision, Area Under Curve(AUC), Sensitivity, Specificity, F1-score, Recall, K-fold, Architecture, Class를 포함한 성능 측정정보를 분석했다. 그 결과로 평균 Accuracy, Precision, AUC, Sensitivity, Specificity 값은 각각 95.2%, 94.81%, 94.01%, 93.5%, 93.92%로 도출되었다. 연도별 성능 측정정보는 점차 증가하는 값을 나타냈고 이 외에도 Class 수, 이미지 데이터 수에 따른 변화율, Architecture 사용 비율, K-fold에 관한 연구를 진행했다. 현재 인공지능을 활용한 COVID-19의 진단은 독자적으로 사용되기에는 여러 문제가 존재하지만, 의사의 보조수단으로써 사용됨에는 부족함이 없을 것으로 예상된다.

• 한국지형학회지
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• 제26권3호
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• pp.53-67
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• 2019

The purpose of this study is to identify the quality of landslide susceptibility in a landslide-prone area (Jinbu-myeon, Gangwon-do, South Korea) by spatial prediction modeling approach and compare the results obtained. For this goal, a landslide inventory map was prepared mainly based on past historical information and aerial photographs analysis (Daum Map, 2008), as well as some field observation. Altogether, 550 landslides were counted at the whole study area. Among them, 182 landslides are debris flow and each group of landslides was constructed in the inventory map separately. Then, the landslide inventory was randomly selected through Excel; 50% landslide was used for model analysis and the remaining 50% was used for validation purpose. Total 12 contributing factors, such as slope, aspect, curvature, topographic wetness index (TWI), elevation, forest type, forest timber diameter, forest crown density, geology, landuse, soil depth, and soil drainage were used in the analysis. Moreover, to find out the co-relation between landslide causative factors and incidents landslide, pixels were divided into several classes and frequency ratio for individual class was extracted. Eventually, six landslide susceptibility maps were constructed using the Bayesian Predictive Discriminant (BPD), Empirical Likelihood Ratio (ELR), and Linear Regression Method (LRM) models based on different category dada. Finally, in the cross validation process, landslide susceptibility map was plotted with a receiver operating characteristic (ROC) curve and calculated the area under the curve (AUC) and tried to extract success rate curve. The result showed that Bayesian, likelihood and linear models were of 85.52%, 85.23%, and 83.49% accuracy respectively for total data. Subsequently, in the category of debris flow landslide, results are little better compare with total data and its contained 86.33%, 85.53% and 84.17% accuracy. It means all three models were reasonable methods for landslide susceptibility analysis. The models have proved to produce reliable predictions for regional spatial planning or land-use planning.

• 대한수의학회지
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• 제44권4호
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• pp.669-676
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• 2004

To evaluate the diagnostic accuracy of two commercial ELISA tests (Allied- and CSL-ELISA) for the diagnosis of Mycobacterium paratuberculosis in cattle, Meta-analysis using English language papers published during 1990-2001 was performed. Diagnostic odds ratios (DOR) were analyzed using regression analysis together with summary receiver operating characteristic (ROC) curves. The difference in diagnostic performance between the two ELISA systems was evaluated by using linear regression. Publication bias was assessed by funnel plot and linear regression. The pooled sensitivity and specificity were 44% (95% CI, 38 to 51) and 98% (95% CI, 96 to 99) for the random-effect model. The DOR between studies was heterogeneous. The area under the fitted ROC curve (AUC) was 0.72 for the unweighted and 0.77 for the weighted model. Maximum joint sensitivity and specificity for the unweighted and weighted model from their summary ROC curve were 70% and 75%, respectively. Based on the fitted model, at a specificity of 95%, sensitivity was estimated to be 52% for the unweighted and 57% for the weighted model. From the final multivariable model study characteristic, the country was the only significant variable with an explained component variance of 13.3%. There were no significant differences in discriminatory power, sensitivity, and specificity between the two ELISA tests. The overall diagnostic accuracy of two commercial ELISA tests was moderate, as judged by the AUC, maximum joint sensitivity and specificity, and estimates from the fitted model and clinical usefulness of the tests for screening program is limited because of low sensitivity and heterogeneous of DOR. It is, therefore, recommended to use ELISA tests as a parallel testing with other diagnostic tests together to increase test sensitivity in the screening program.

• 대한간호학회지
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• 제42권3호
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• pp.414-423
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• 2012

Purpose: The aims of this study were to develop and test the validity of the Korean Nursing Delirium Scale (Nu-DESC) for older patients in hospital. Methods: The Korean Nu-DESC was developed based on the Nu-DESC (Gaudreau, 2005), and revised according to nursing records related to signs and symptoms of older patients with delirium (n=361) and the results of a pilot study (n=42) in one general hospital. To test the validity of the Korean Nu-DESC, 75 older patients whom nurses suspected of delirium from 731 older patients from 12 nursing units were assessed by bedside nurses using the Korean Nu-DESC. A Receiver Operating Characteristic Curve of the Korean Nu-DESC was constructed with an accompanying Area Under the Curve (AUC). Results: Specific examples such as irritable, kidding, sleeping tendency, which were observed by bedside nurses in Korea, were identified in the five features of signs and symptoms of delirium in the instrument. The Korean Nu-DESC was psycho-metrically valid and had a sensitivity and specificity of .81-.76 and .97-.73, respectively. The AUC were .89, .74. Conclusion: Results of this study indicate that the Korean Nu-DESC is well-suited for widespread clinical use in busy inpatients settings and shows promise as a research instrument.

• 가정∙방문간호학회지
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• 제30권1호
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• pp.48-58
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• 2023

Purpose: The purpose of this study was to construct a nomogram for predicting difficulty in peripheral intravenous cannulation (DPIVC) for adult inpatients. Methods: This study conducted a secondary analysis of data from the intravenous cannulation cohort by intravenous specialist nurses at a tertiary hospital in Seoul. Overall, 504 patients were included; of these, 166 (32.9%) patients with failed cannulation in the first intravenous cannulation attempt were included in the case group, while the remaining 338 patients were included in the control group. The nomogram was built with the identified risk factors using a multiple logistic regression analysis. The model performance was analyzed using the Hosmer-Lemeshow test, area under the curve (AUC), and calibration plot. Results: Five factors, including vein diameter, vein visibility, chronic kidney disease, diabetes, and chemotherapy, were risk factors of DPIVC. The nomogram showed good discrimination with an AUC of 0.81 (95% confidence interval: 0.80-0.82) by the sample data and 0.79 (95% confidence interval: 0.74-0.84) by bootstrapping validation. The Hosmer-Lemeshow goodness-of-fit test showed a p-value of 0.694, and the calibration curve of the nomogram showed high coherence between the predicted and actual probabilities of DPIVC. Conclusion: This nomogram can be used in clinical practice by nurses to predict DPIVC probability. Future studies are required, including those on factors possibly affecting intravenous cannulation.

• Clinical and Experimental Pediatrics
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• 제64권7호
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• pp.347-354
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• 2021

Background: Neutrophil gelatinase-associated lipocalin (NGAL) has emerged as a valuable biomarker of urinary tract infection (UTI) in children. Purpose: This study aimed to compare the diagnostic accuracy of urinary NGAL (uNGAL) with those of serum C-reactive protein (CRP) and white blood cell (WBC) count for predicting UTI and acute pyelonephritis (APN) in febrile children. Methods: The medical charts of children undergoing uNGAL measurements between November 2017 and August 2019 were retrospectively reviewed. Patients with a suspected or diagnosed UTIs were included. The diagnostic accuracies of uNGAL, serum CRP, and WBC count for detecting UTI and APN were investigated. Independent predictors of UTI and APN were investigated using multivariable logistic regression analyses. Results: A total of 321 children were enrolled in this study. The uNGAL levels were higher in the UTI group (n=157) than in the non-UTI group (n=164) (P<0.05). Among children with a UTI, uNGAL levels were higher in the APN group (n=70) than, the non-APN group (n=87) (P<0.05). In the multivariate analysis, uNGAL was independently associated with UTI and APN (both P<0.05). Serum CRP and WBC count were not correlated with the presence of UTI and APN. Receiver operating curve analyses showed that the uNGAL level had the highest area under the curve (AUC) for predicting UTI and APN, respectively (AUC, uNGAL vs. CRP vs. WBC count, 0.860 vs. 0.608 vs. 0.669 for UTI; 0.780 vs. 0.680 vs. 0.639 for APN, all P<0.05, respectively). The predictive values and likelihood ratios of uNGAL were superior to those of serum CRP and WBC count for detecting UTI and APN at each cutoff level. Conclusion: UNGAL may be more useful than serum CRP and WBC count for identifying and assessing UTI in febrile children.

• 한국음향학회지
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• 제42권3호
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• pp.262-269
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• 2023

본 논문에서는 선형 예측 분석을 기반으로 한 딱총새우 잡음 검출을 위한 특징을 제안한다. 딱총새우는 천해에 서식하는 종으로, 높은 진폭의 신호를 생성하고 빈번하게 발생하기 때문에 수중 잡음의 주된 원인 중 하나이다. 제안된 특징은 딱총새우 잡음이 갑작스럽게 발생하고 빠르게 소멸하는 특징을 활용하기 위해 선형 예측 분석을 이용하여 정확한 잡음 구간을 검출하고 딱총새우 잡음의 영향을 줄인다. 선형 예측 분석으로 예측한 값과 실제 측정값 사이의 오차가 크기 때문에 이를 통해 효과적으로 딱총새우 구간 검출이 가능해진다. 추가적으로 제안된 특징에 일정 오경보 확률 탐지기를 결합하여 잡음 구간 검출 성능을 추가적으로 개선한다. 제안한 방법을 딱총새우 잡음 구간 검출 최신 방법으로 알려진 다층 웨이블릿 패킷 분해와 비교한 결과, 제안한 방법이 수신자 조작 특성 곡선과 곡선 아래의 면적 측면에서 성능이 평균적으로 0.12만큼 우수하였고 계산량 측면에서도 계산 복잡도가 더 낮았다.

• Asian Pacific Journal of Cancer Prevention
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• 제15권18호
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• pp.7583-7588
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• 2014

Background: Colorectal cancer (CRC) is a major cause of cancer-related death and cancer-related incidence worldwide. The potential of microRNA-21 (miR-21) as a biomarker for CRC detection has been studied in several studies. However, the results were inconsistent. Therefore, we conducted the present meta-analysis to systematically assess the diagnostic value of miR-21 for CRC. Materials and Methods: Using a random-effect model, the pooled sensitivity (SEN), specificity (SPE), positive likelihood ratio (PLR), negative likelihood ratio (NLR), and diagnostic odds ratio (DOR) were calculated to evaluate the diagnostic performance of miR-21 for CRC. A summary receiver operating characteristic (SROC) curve and an area under the curve (AUC) were also generated to assess the diagnosis accuracy of miR-21 for CRC. Q test and I2 statistics were used to assess between-study heterogeneity. Publication bias was evaluated by the Deeks' funnel plot asymmetry test. Results: A total of 986 CRC patients and 702 matched healthy controls from 8 studies were involved in the meta-analysis. The pooled results for SEN, SPE, PLR, NLR, DOR, and AUC were 57% (95%CI: 39%-74%), 87% (95%CI: 78%-93%), 4.4 (95%CI: 2.4-8.0), 0.49 (95%CI: 0.32-0.74), 9 (95%CI: 4-22), and 0.83 (95%CI: 0.79-0.86), respectively. Subgroup analyses further suggested that blood-based studies showed a better diagnostic accuracy compared with feces-based studies, indicating that blood may be a better matrix for miR-21 assay and CRC detection. Conclusions: Our findings suggest that miR-21 has a potential diagnostic value for CRC with a moderate level of overall diagnostic accuracy. Hence, it could be used as auxiliary means for the initial screening of CRC and avoid unnecessary colonoscopy, which is an invasive and expensive procedure.

• 대한종양외과학회지
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• 제14권2호
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• pp.135-141
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• 2018

Purpose: Axillary lymph node dissection (ALND) and sentinel lymph node biopsy (SLNB) are important for staging of patients with node-positive breast cancer. However, these can be avoided in select micrometastatic diseases, preventing postoperative complications. The present study evaluated the ability of axillary lymph node maximum standardized uptake value (SUVmax) on positron emission tomography-computed tomography (PET-CT) to predict axillary metastasis of breast cancer. Methods: The records of invasive breast cancer patients who underwent pretreatment (surgery and/or chemotherapy) PET-CT between January 2006 and December 2014 were reviewed. ALNs were preoperatively evaluated by PET-CT. Lymph nodes were dissected by SLNB or ALND. SUVmax was measured in both the axillary lymph node and primary tumor. Student t-test and chi-square test were used to analyze sensitivity and specificity. Receiver operating characteristic (ROC) and area under the ROC curve (AUC) analyses were performed. Results: SUV-tumor (SUV-T) and SUV-lymph node (SUV-LN) were significantly higher in the triple-negative breast cancer (TNBC) group than in other groups (SUV-T: 5.99, P<0.01; SUV-LN: 1.29, P=0.014). The sensitivity (0.881) and accuracy (0.804) for initial ALN staging were higher in fine needle aspiration+PET-CT than in other methods. For PET-CT alone, the subtype with the highest sensitivity (0.870) and negative predictive value (0.917) was TNBC. The AUC for SUV-LN was greatest in TNBC (0.797). Conclusion: The characteristics of SUV-T and SUV-LN differed according to immunohistochemistry subtype. Compared to other subtypes, the true positivity of axillary metastasis on PET-CT was highest in TNBC. These findings could help tailor management for therapeutic and diagnostic purposes.