scholarly journals Score Fusion by Maximizing the Area under the ROC Curve

2009 ◽  
pp. 473-480 ◽  
Author(s):  
Mauricio Villegas ◽  
Roberto Paredes
Keyword(s):  
Roc Curve ◽  
Score Fusion

Head Position Identification

1967 ◽  
Vol 10 (3) ◽  
pp. 438-448
Author(s):  
H. N. Wright
Keyword(s):  
Roc Curve ◽  
Head Position ◽  
Hearing Impaired ◽  
Type Ii ◽  
Experimental Conditions ◽  
Partial Explanation ◽  
Complex Sounds ◽  
Binaural Cues ◽  
Criterion Behavior ◽  
Stimulus Degradation

A binaural recording of traffic sounds that reached an artificial head oriented in five different positions was presented to five subjects, each of whom responded under four different criteria. The results showed that it is possible to examine the ability of listeners to localize sound while listening through earphones and that the criterion adopted by an individual listener is independent of his performance. For the experimental conditions used, the Type II ROC curve generated by manipulating criterion behavior was linear and consistent with a guessing model. Further experiments involving different degrees of stimulus degradation suggested a partial explanation for this finding and illustrated the various types of monaural and binaural cues used by normal and hearing-impaired listeners to localize complex sounds.

Prediction of Post spinal anesthesia hypotension in patients undergoing cesarean section using Perfusion index

2020 ◽  
Vol 5 (3) ◽  
pp. 1241-1245
Author(s):  
Kumud Pyakurel ◽  
Lalit Kumar Rajbanshi ◽  
Ramesh Bhattarai ◽  
Sonia Dahal
Keyword(s):  
Spinal Anesthesia ◽  
Cesarean Delivery ◽  
Supine Position ◽  
Roc Curve ◽  
Anesthetic Management ◽  
College Teaching ◽  
Perfusion Index ◽  
Sensory Level ◽  
Roc Curve Analysis ◽  
Group I

Introduction: Spinal anesthesia induced hypotension frequently complicates Cesarean delivery. This is usually due to sudden sympatholysis causing decreased venous return which can be aggravated by physiological changes of pregnancy leading to change in baseline peripheral vascular tone. Strategies to prevent hypotensive episodes should be the primary aim of anesthetic management. A simple noninvasive measurement of perfusion index derived from pulse oximeter predicting hypotension during the routine intraoperative course could provide a new dynamism to the management and improving the safe execution of anesthesia. Objectives: The primary objective of this study was to compare incidence of hypotension following SAB for LSCS in patients with baseline PI ≤ 3.5 to those with PI > 3.5. The secondary objectives were to compare PI, HR, SBP, MAP at various time intervals and also to study the side effects between the two groups. Methodology: This prospective observational study was conducted at Nobel Medical College Teaching Hospital from to July 2019 to October 2019. 73 Term parturients presenting for elective cesarean delivery were included for the study. Upon arrival in the operation room, standard monitors were attached and baseline HR, SBP, DBP, MAP, PI and SPO2 were recorded in supine position. The patients with baseline PI ≤ 3.5 were enrolled into Group I and those with a PI > 3.5 were enrolled into Group II. Spinal Anesthesia with 10mg of 0.5% heavy Bupivacaine and 20mcg Fentanyl ( total 2.4ml) was given at L3-L4 interspace in sitting position using midline approach. Patient was then returned to supine position with left lateral tilt of 15 degrees to facilitate left uterine displacement. Upper sensory level was checked at 5 minutes using alcohol swab. Once T-6 level was reached, surgery was started. Maternal SBP, DBP, MAP, HR and PI were recorded at 1 minute intervals between spinal injection and delivery and then 3 minutes until end of surgery. Clinically relevant hypotension was defined as the decrease in MAP by 20% or more from baseline value. Results: The incidence of hypotension in Group I was 18.8% (6/30) compared to 81.3% (26/38). This was clinically and statistically highly significant (P = 0.000, odds ratio 0.11). On Spearman’s rank correlation we found highly significant correlation between baseline PI >3.5 and number of episodes of hypotension (rs 0.482, P = 0.000). The sensitivity and specificity of baseline PI with cut-off 3.5 for predicting hypotension were 81.3% and 66.7% respectively. The ROC curve analysis showed 3.53 as appropriate cut‑off for our findings. The area under the ROC curve (AUC) was 0.734 [Figure 6](Lower bound 0.608 and upper bound 0.861, P=0.001).  Conclusion : This study demonstrates that baseline PI of > 3.5 correlates with incidence of hypotension after spinal anesthesia for cesarean delivery in healthy parturients compared to a baseline PI of < 3.5.

VALUE OF COMBINATION OF HAP SCORE AND BISAP SCORE IN PREDICTING SEVERITY IN PATIENTS OF ACUTE PANCREATITIS

2019 ◽  
pp. 96-100
Author(s):  
Thi Ngoc Suong Le ◽  
Pham Chi Tran ◽  
Van Huy Tran
Keyword(s):  
Acute Pancreatitis ◽  
Positive Predictive Value ◽  
Roc Curve ◽  
Predictive Value ◽  
Prognostic Value ◽  
Acute Inflammation ◽  
Clinical Symptoms ◽  
Mortality Rates ◽  
Multiple Organ ◽  
Central Hospital

Acute pancreatitis (AP) is an acute inflammation of the pancreas, usually occurs suddenly with a variety of clinical symptoms, complications of multiple organ failure and high mortality rates. Objectives: To determine the value of combination of HAP score and BISAP score in predicting the severity of acute pancreatitis of the Atlanta 2012 Classification. Patients and Methods: 75 patients of acute pancreatitis hospitalized at Hue Central Hospital between March 2017 and July 2018; HAP and BISHAP score is calculated within the first 24 hours. The severity of AP was classified by the revised Atlanta criteria 2012. Results: When combining the HAP and BISAP scores in predicting the severity of acute pancreatitis, the area under the ROC curve was 0,923 with sensitivity value was 66.7%, specificity value was 97.1%; positive predictive value was 66.7%, negative predictive value was 97.1%. Conclusion: The combination of HAP and BISAP scores increased the sensitivity, predictive value, and prognostic value in predicting the severity of acute pancreatitis of the revised Atlanta 2012 classification in compare to each single scores. Key words: HAPscore, BiSAP score, acute pancreatitis, predicting severity

Expression Levels of MicroRNA-125b in Serum Exosomes of Patients with Asthma of Different Severity and its Diagnostic Significance

2019 ◽  
Vol 20 (10) ◽  
pp. 781-784 ◽  
Author(s):  
Meizhen Zhao ◽  
Li Juanjuan ◽  
Fan Weijia ◽  
Xie Jing ◽  
Huang Qiuhua ◽  
...  
Keyword(s):  
Correlation Analysis ◽  
Roc Curve ◽  
Quantitative Polymerase Chain Reaction ◽  
Persistent Asthma ◽  
Asthma Severity ◽  
Control Group ◽  
Spearman Correlation ◽  
Diagnostic Efficacy ◽  
Expression Levels ◽  
Serum Exosomes

Background: This study aimed to investigate the expression levels of microRNA (miRNA)-125b in serum exosomes and its diagnostic efficacy for asthma severity. Methods: The study included 80 patients with untreated asthma and 80 healthy volunteers. The patients were divided into 4 groups according to disease severity: 20 with the intermittent state, 20 with the mildly persistent state, 20 with the moderately persistent state, and 20 with the severely persistent state. The expression levels of miRNA-125b in serum exosomes of each group were detected using a quantitative polymerase chain reaction and compared. The Spearman correlation analysis was used to study the correlation between the expression levels of miRNA-125b in serum exosomes and asthma severity. The diagnostic efficacy of the expression levels of miRNA-125b in exosomes for asthma severity was evaluated using the Receiver Operating Characteristic (ROC) curve. Results: The expression levels of miRNA-125b in serum exosomes of patients with intermittent, mildly persistent, moderately persistent, and severely persistent asthma were all higher than those in the healthy control group, with statistically significant differences. The expression levels of miRNA-125b were also statistically significantly different among patients in each group. The Spearman correlation analysis showed a positive correlation of the relative expression of miRNA-125b in serum exosomes with asthma severity. The area under the ROC curve of the diagnostic efficacy of miRNA-125b in serum exosomes for patients with intermittent, mildly, moderately, and severely persistent asthma was 0.7770, 0.8573, 0.9111, and 0.9995, respectively. Conclusion: The expression levels of miRNA-125b in serum exosomes had a high diagnostic efficacy and might serve as a noninvasive diagnostic marker for asthma severity.

New Hybrid Method for Left Ventricular Ejection Fraction Assessment from Radionuclide Ventriculography Images

2020 ◽  
Vol 16 ◽  
Author(s):  
Halima Dziri ◽  
Mohamed Ali Cherni ◽  
Dorra Ben Sellem
Keyword(s):  
Left Ventricular Ejection Fraction ◽  
Left Ventricle ◽  
Ejection Fraction ◽  
Positive Predictive Value ◽  
Roc Curve ◽  
Radionuclide Ventriculography ◽  
Left Ventricular ◽  
The Other ◽  
Left Ventricular Ejection ◽  
Ventricular Ejection Fraction

Background: In this paper, we propose a new efficient method of radionuclide ventriculography image segmentation to estimate the left ventricular ejection fraction. This parameter is an important prognostic factor for diagnosing abnormal cardiac function. Methods: The proposed method combines the Chan-Vese and the mathematical morphology algorithms. It was applied to diastolic and systolic images obtained from the Nuclear Medicine Department of Salah AZAIEZ Institute.In order to validate our proposed method, we compare the obtained results to those of two methods of the literature. The first one is based on mathematical morphology, while the second one uses the basic Chan-Vese algorithm. To evaluate the quality of segmentation, we compute accuracy, positive predictive value and area under the ROC curve. We also compare the left ventricle ejection fraction estimated by our method to that of the reference given by the software of the gamma-camera and validated by the expert, using Pearson’s correlation coefficient, ANOVA test and linear regression. Results and conclusion: Static results show that the proposed method is very efficient in the detection of the left ventricle. The accuracy was 98.60%, higher than that of the other two methods (95.52% and 98.50%). Likewise, the positive predictive value was the highest (86.40% vs. 83.63% 71.82%). The area under the ROC curve was also the most important (0.998% vs. 0.926% 0.919%). On the other hand, Pearson's correlation coefficient was the highest (99% vs. 98% 37%). The correlation was significantly positive (p<0.001).

scholarly journals Wound Infections of Snakebites from the Venomous Protobothrops mucrosquamatus and Viridovipera stejnegeri in Taiwan: Bacteriology, Antibiotic Susceptibility, and Predicting the Need for Antibiotics—A BITE Study

Toxins ◽  
2020 ◽  
Vol 12 (9) ◽  
pp. 575 ◽  
Author(s):  
Chih-Chuan Lin ◽  
Yen-Chia Chen ◽  
Zhong Ning Leonard Goh ◽  
Chen-Ken Seak ◽  
Joanna Chen-Yeen Seak ◽  
...  
Keyword(s):  
Wound Infection ◽  
Roc Curve ◽  
Predictive Performance ◽  
Antibiotic Usage ◽  
Emergency Department Visits ◽  
Treatment Modalities ◽  
Wound Infections ◽  
Neutrophil Lymphocyte Ratio ◽  
Cell Counts ◽  
Freeze Dried

Snakebites from Taiwan habus (Protobothrops mucrosquamatus) and green bamboo vipers (Viridovipera stejnegeri) account for two-thirds of all venomous snakebites in Taiwan. While there has been ongoing optimization of antivenin therapy, the proper management of superimposed bacterial wound infections is not well studied. In this Bacteriology of Infections in Taiwanese snake Envenomation (BITE) study, we investigated the prevalence of wound infection, bacteriology, and corresponding antibiotic usage in patients presenting with snakebites from these two snakes. We further developed a BITE score to evaluate the probability of wound infections and guide antibiotic usage in this patient population. All snakebite victims who presented to the emergency departments of seven training and research hospitals and received at least one vial of freeze-dried hemorrhagic antivenin between January 2001 and January 2017 were identified. Patient biodata, laboratory investigation results, and treatment modalities were retrieved. We developed our BITE score via univariate and multiple logistic regression analyses. The receiver operating characteristic (ROC) curve was plotted to evaluate the predictive performance of the BITE score. Out of 8,295,497 emergency department visits, 726 patients presented with snakebites from a Taiwan habu or a green bamboo viper. The wound infection rate was 22.45%, with seven positive wound cultures, including six polymicrobial infections. Morganella morganii, Enterococcus spp., Bacteroides fragilis, and Aeromonas hydrophila were most frequently cultured. There were no positive blood cultures. A total of 33.0% (n = 106) of snakebite patients who received prophylactic antibiotics nevertheless developed wound infections, while 44.8% (n = 73) of wound infection patients were satisfactorily treated with one of the following antibiotics: amoxicillin/clavulanic acid, oxacillin, cefazolin, and ampicillin/sulbactam. With the addition of gentamicin, the success of antibiotic therapy increased by up to 66.54%. The prognostic factors for the secondary bacterial infection of snakebites were white blood cell counts, the neutrophil lymphocyte ratio, and the need for hospital admission. The area under the ROC curve for the BITE score was 0.839. At the optimal cut-off point of 5, the BITE score had a 79.58% accuracy, 82.31% sensitivity, and 79.71% specificity when predicting infection in snakebite patients. Our BITE score may help with antibiotic stewardship by guiding appropriate antibiotic use in patients presenting with snakebites. It may also be employed in further studies into antibiotic prophylaxis in snakebite patients for the prevention of superimposed bacterial wound infections.

Baseline apparent diffusion coefficients: Validation study of new predictor of survival in patients with unresectable hepatocellular carcinoma following chemoembolization

2021 ◽  
pp. 1-10
Author(s):  
Lichao Xu ◽  
Shiqin Wang ◽  
Shengping Wang ◽  
Ying Wang ◽  
Wentao Li ◽  
...  
Keyword(s):  
Hepatocellular Carcinoma ◽  
Roc Curve ◽  
Cox Regression ◽  
Response To Treatment ◽  
Roc Curve Analysis ◽  
Adc Value ◽  
Apparent Diffusion Coefficients ◽  
Apparent Diffusion ◽  
Response Biomarker ◽  
The Difference

OBJECTIVES: To investigate whether the baseline apparent diffusion coefficient (ADC) can predict survival in the hepatocellular carcinoma (HCC) patients receiving chemoembolization. MATERIALS AND METHODS: Diffusion-weighted MR imaging of HCC patients is performed within 2 weeks before chemoembolization. The ADC of the largest index lesion is recorded. Responses are assessed by mRECIST after the start of the second course of chemoembolization. Receiver operating characteristic (ROC) curve analysis is performed to evaluate the diagnostic performance and determine optimal cut-off values. Cox regression and Kaplan–Meier survival analyses are used to explore the differences in overall survival (OS) between the responders and non-responders. RESULTS: The difference is statistically significant in the baseline ADC between the responders and non-responders (P <  0.001). ROC analyses indicate that the baseline ADC value is a good predictor of response to treatment with an area under the ROC curve (AUC) of 0.744 and the optimal cut-off value of 1.22×10–3 mm2/s. The Cox regression model shows that the baseline ADC is an independent predictor of OS, with a 57.2% reduction in risk. CONCLUSION: An optimal baseline ADC value is a functional imaging response biomarker that has higher discriminatory power to predict tumor response and prolonged survival following chemoembolization in HCC patients.

scholarly journals The value of glycosylated hemoglobin in the diagnosis of diabetic retinopathy: a systematic review and Meta-analysis

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Bo Zhang ◽  
Bingjie Zhang ◽  
Zhulin Zhou ◽  
Yutong Guo ◽  
Dan Wang
Keyword(s):  
Diabetic Retinopathy ◽  
Likelihood Ratio ◽  
Roc Curve ◽  
Meta Analysis ◽  
Glycosylated Hemoglobin ◽  
Positive Likelihood Ratio ◽  
Negative Likelihood Ratio ◽  
Biomedical Literature ◽  
Cochrane Library ◽  
Clinical Value

AbstractObjectiveGlycosylated hemoglobin (HbA1c) has obvious clinical value in the diagnosis of diabetes, but the conclusions on the diagnostic value of diabetic retinopathy (DR) are not consistent. This study aims to comprehensively evaluate the accuracy of glycosylated hemoglobin in the diagnosis of diabetic retinopathy through the meta-analysis of diagnostic tests.MethodsCochrane Library, Embase, PubMed, Web of Science, China National Knowledge Infrastructure (CNKI), China Wanfang Database, Chinese Biomedical Literature Database (CBM) were searched until November, 2020. The Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) tool was used to assess the quality of the included studies. The pooled sensitivity, specificity, positive likelihood ratio (+LR), negative likelihood ratio (-LR), diagnostic odds ratio (DOR) and areas under the receiver operating characteristic (ROC) curve were calculated by Stata 15.0 software.ResultsAfter screening, 18 high-quality papers were included. The results of meta-analysis showed that the combined DOR = 18.19 (95% CI: 10.99–30.11), the sensitivity= 0.81 (95% CI): 0.75 ~ 0.87), specificity = 0.81 (95%CI: 0.72 ~ 0.87), +LR = 4.2 (95%CI: 2.95 ~ 6.00), −LR = 0.23 (95%CI: 0.17 ~ 0.31), and the area under the Summary ROC curve was 0.88 (95%CI:  0.85 ~ 0.90).ConclusionThe overall accuracy of HbA1cC forin diagnosing diabetic retinopathy is good. As it is more stable than blood sugar and is not affected by meals, it may be a suitable indicator for diabetic retinopathy.

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