• Proceedings of the Korean Society of Medical Physics Conference
• /
• 1999.11a
• /
• pp.124-125
• /
• 1999

• Communications for Statistical Applications and Methods
• /
• v.17 no.2
• /
• pp.275-292
• /
• 2010

Receiver operating characteristic(ROC) curves can be used to assess the accuracy of tests measured on ordinal or continuous scales. The most commonly used measure for the overall diagnostic accuracy of diagnostic tests is the area under the ROC curve(AUC). When two ROC curves are constructed based on two tests performed on the same individuals, statistical analysis on differences between AUCs must take into account the correlated nature of the data. This article focuses on confidence interval estimation of the difference between paired AUCs. We compare nonparametric, maximum likelihood, bootstrap and generalized pivotal quantity methods, and conduct a monte carlo simulation to investigate the probability coverage and expected length of the four methods.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.37 no.6
• /
• pp.797-804
• /
• 2013

In this study, the authors develop a methodology for a diagnostic system with a vibration parameter that is influenced by environmental factors. The data tends to have a varying average over time. Often, these features are found in statistical data retrieved from a production line. If we utilize existing statistical techniques for these features, we could derive an incorrect diagnostic conclusion based on the different average values. To overcome the limitations of previous methods, the authors apply a function analyzed through regression analysis to predict the mean value and corresponding upper and lower limits at each stage. This technique also provides corresponding statistical parameters in varying dynamic means. To validate the proposed methods, we retrieve data from the engine assembly line of H Motors and verify the results.

• Journal of Oral Medicine and Pain
• /
• v.41 no.3
• /
• pp.91-98
• /
• 2016

Purpose: Oral lichen planus (OLP) has generated many discussions and been associated with much controversy for a long time. A reliable diagnosis of OLP has proven challenging and significant disagreements concerning its diagnosis has continued. Therefore, the aim of this study was to apprehend newly proposed diagnostic criteria of OLP and oral lichenoid lesion (OLL) and to evaluate difference of final diagnosis of OLP and OLL in accordance with type of diagnostic criteria. Also, direct immunofluorescence (DIF) was compared to evaluate the value of DIF between two groups. Methods: Fifty-two patients with DIF result were retrospectively reviewed. The selected patients were classified by the modified World Health Organization (WHO) diagnostic criteria of OLP and OLL and by criteria proposed by American Academy of Oral and Maxillofacial Pathology (AAOMP). Results of DIF in OLP and OLL were classified by deposition intensity or pattern of fibrinogen. The classification of fluorescence pattern in each specimen was graded as positive, possibly positive or negative. Results: Patients diagnosed as OLP were a few more when the modified WHO diagnostic criteria were used than when criteria proposed by AAOMP were used. There was no statistical difference of DIF between OLP and OLL by applying the WHO modification criteria or criteria proposed by AAOMP. Conclusions: The final diagnosis of OLP could be changed in accordance with type of diagnostic criteria and difference of DIF between OLP and OLL was not found.

• Journal of IKEEE
• /
• v.12 no.2
• /
• pp.87-94
• /
• 2008

Pelvic floor muscle is the main subsystem that maintains urinary continence. It is possible to diagnose the degree of the stress urinary incontinence(SUI) by evaluating the contraction pressure of the pelvic floor muscle. Bio-signal measurement system was developed to measure the contraction pressure. Diagnostic parameters were drawn out by analyzing the measured data. Statistical evaluations were done to classify the all subjects with five groups each has similar characteristics. SUI diagnostic algorithm was implemented to each group separately. The accuracy of the algorithm was about 78.9% and utility was confirmed by clinical trial.

• Asian Pacific Journal of Cancer Prevention
• /
• v.15 no.5
• /
• pp.2341-2344
• /
• 2014

Background: p53 protein expression has been detected immunohistochemically in papillary thyroid carcinoma(PTC). We investigated the relations between its expression and clinicopathologic features and its significance as a diagnostic marker. Materials and Methods: We compared and evaluated 93 patients in whom thyroidectomy with lymph node dissection had been performed to treat PTC for clinicopathologic significance and 102 patients with 23 papillary thyroid overt carcinomas (POC), 57 papillary thyroid microcarcinomas(PMC), 5 follicular adenomas (FA), 5 Hashimoto's thyroiditis (HT) and 12 nodular hyperplasias (NH) for significance as a diagnostic marker. Expression of p53 protein was evaluated immunohistochemically in sections of paraffinembedded tissue. Results: Statistical analysis showed significantly different expression of p53 in PTC versus other benign thyroid lesions (BTL).The diagnostic sensitivity and specificity were 85.0% and 72.7%, respectively. Overexpression of p53 protein was observed in 44 of the 93 PTC cases (47.3%), but no significant correlation between p53 protein overexpression and clinicopathologic features (age, size, multiplicity, lymph node metastasis, extrathyroidal extension and vascular invasion) was noted. Conclusions: p53 is valuable to distinguish PTC from other BTL, but there is no correlation between p53 protein overexpression and clinicopathologic features.

• Journal of radiological science and technology
• /
• v.43 no.5
• /
• pp.367-374
• /
• 2020

The purpose of this study is to understand the infection prevention system and infection management perception of Ultrasound diagnostic room in medical institutions by sonographer's in general practitioner, semi and general hospitals. As a research method, a statistical analysis was conducted by surveying a total of 20 items in four category to determine the infection perception of sonographer's according to gender, age, working institution, and working period. As a result of infection awareness, males were in the ultrasound gel management category, women were in the transducer management category, all age groups were in the transducer management system category, and the General Practitioner, semi and general hospitals. were in the transducer management system category, and general hospitals showed a high degree of infection awareness in the category of disinfection and sterilization, and in the category of transducer management in the entire working period. In the results of the analysis of the correlation between the sub-factors of the perception of infection control in the Ultrasound diagnostic room the degree of correlation between each category showed a middle degree correlation(r>0.5) and a significant difference by category(p<.01). In conclusion, the prevention of infection in the ultrasound diagnostic room, which sonographer's firms think, was found to be the most efficient ultrasound diagnostic room infection control to implement transducer and gel management in accordance with the principles of disinfection and sterilization.

• Journal of rehabilitation welfare engineering & assistive technology
• /
• v.1 no.1
• /
• pp.13-19
• /
• 2007

In this study, diagnostic algorithm was suggested to diagnose quantitatively the degree of the stress urinary incontinence. The bio-signal measurement system was developed to measure the contraction pressure of the pelvic floor muscle and diagnostic parameters were drawn out by analyzing the contraction pressure data. Statistical evaluations were done to classify the diagnositc parameters by order that relationship is high. The diagnostic algorithm that was able to diagnose degree of the urinary incontinence as quantitatively was realized from the high relationship parameters.

• Journal of Korean Society of Rural Planning
• /
• v.27 no.2
• /
• pp.91-104
• /
• 2021

The purpose of this study is to develop the diagnostic indices system that can be applied to the evaluation of rural village level, because the indicators developed in many existing studies were mostly consisted of statistical data in higher level than rural villages as well as those were difficult to apply to rural village level empirically. In order to develop the empirical diagnostic indices system, which has 52 indices with 7 categories, this study not only classified the kind of rural village facility and the regional development project of government, but also surveyed the specialist opinion with Delphi method. Especially, this study standardized the all diagnostic indices with positive value to remove the indices with negative values. Finally, the results that the study applied the empirical diagnostic indices to the 15 sample villages of Jinan-gun and Cheongyang-gun showed that there was the applicability of the indices system in the village level.

• Imaging Science in Dentistry
• /
• v.45 no.2
• /
• pp.73-80
• /
• 2015

Purpose: This study evaluated the effect of various head orientations during cone-beam computed tomography (CBCT) image acquisition on linear measurements of potential implant sites. Materials and Methods: Six dry human skulls with a total of 28 implant sites were evaluated for seven different head orientations. The scans were acquired using a Hitachi CB-MercuRay CBCT machine. The scanned volumes were reconstructed. Horizontal and vertical measurements were made and were compared to measurements made after simulating the head position to corrected head angulations. Data was analyzed using a two-way ANOVA test. Results: Statistical analysis revealed a significant interaction between the mean errors in vertical measurements with a marked difference observed at the extension head position (P<0.05). Statistical analysis failed to yield any significant interaction between the mean errors in horizontal measurements at various head positions. Conclusion: Head orientation could significantly affect the vertical measurements in CBCT scans. The main head position influencing the measurements is extension.