• Journal of Korean Neurosurgical Society
• /
• v.59 no.6
• /
• pp.577-583
• /
• 2016

Objective : The inter-rater reliability of the modified Knosp's classification was measured before the analysis. The clinical validity of the parasellar extension grading system was evaluated by investigating the extents of resection and complication rates among the grades in the endoscopic endonasal transsphenoidal surgery (EETS) for pituitary adenomas. Methods : From November 2008 to August 2015, of the 286 patients who underwent EETS by the senior author, 208 were pituitary adenoma cases (146 non-functioning pituitary adenomas, 10 adrenocorticotropic hormone-secreting adenomas, 31 growth hormone-secreting adenomas, 17 prolactin-secreting adenomas, and 4 thyroid-stimulating hormone-secreting adenomas; 23 microadenomas, 174 macroadenomas, and 11 giant adenomas). Two neurosurgeons and a neuroradiologist independently measured the degree of parasellar extension on the preoperative sellar MRI according to the modified Knosp's classification. Inter-rater reliability was statistically assessed by measuring the intraclass correlation coefficient. The extents of resection were evaluated by comparison of the pre- and post-operative MR images; the neurovascular complications were assessed by reviewing the patients' medical records. The extent of resection was measured in each parasellar extension grade; thereafter, their statistical differences were calculated. Results : The intraclass correlation coefficient value of reliability across the three raters amounted to 0.862. The gross total removal (GTR) rates achieved in each grade were 70.0, 69.8, 62.9, 21.4, 37.5, and 4.3% in Grades 0, 1, 2, 3A, 3B, and 4, respectively. A significant difference in the extent of resection was observed only between Grades 2 and 3A. In addition, significantly higher complication rates were observed in the groups above Grade 3A. Conclusion : Although the modified Knosp's classification system appears to be complex, its inter-rater reliability proves to be excellent. Regarding the clinical validity of the parasellar extension grading system, Grades 3A, 3B, and 4 have a negative predictive value for the GTR rate, with higher complication rates.

• Journal of Preventive Medicine and Public Health
• /
• v.35 no.4
• /
• pp.359-374
• /
• 2002

Objectives : To develop a physical functioning instrument for older adults living in the community. Methods : A representative sample of 979 people aged 65 years or over were interviewed in-person. Of these, 199 people also completed a detailed in-hospital examination. The scale items were selected based on the frequency of endorsement, along with the item-total and inter-item correlations. The associations of the scale with their physical performance and clinical examination were analyzed to evaluate the criterion-related validity. Construct validity was assessed using factor analysis, and internal consistency through Cronbach's alpha and item-total correlations. Test-retest reliability was measured by agreement between the household survey and the repeat survey at the in-hospital examination. Results : Initially, 23 items on the level of difficulty, ranging from no difficulty to an inability to complete a task, with the specific mobility and self-care tasks were included. Those with a high frequency of endorsement and a low inter-item or item-total correlations were excluded, resulting in a 10-item Physical Functioning (PT) scale. Equal weights were given to each item and a summated score was calculated. Significant associations were found between the PF scores and the physical performance, surrey and clinical data. The scale revealed a 2-factor (mobility and self-care) structure. Cronbach's alpha was 0.92 and the item-total correlations were in the 0.63 to 0.78 range. Pearson's correlations for the test-retest ranged between 0.56 and 0.61. Conclusions : The newly developed Physical Functioning (PF) scale showed good psychometric properties in older people. Further work, however, is needed to improve its sensitivity to discriminate higher levels of functioning, in addition to assessing its predictive value in detecting changes in health.

• The Journal of the Korea Contents Association
• /
• v.20 no.12
• /
• pp.393-405
• /
• 2020

The purpose of this study is to develop and validate a scale of vicarious trauma for sexual violence counselors. To this end, the concept of composition and preliminary questions of the vicarious trauma of sexual violence counselors were selected through the analysis of a content of individual interviews of sexual violence counselors and the precedent theory. Then, preliminary scale was developed after expert's evaluation of the validity of the contents. Next, as a result of a confirmatory factor analysis on the preliminary scale of 349 sexual violence counselors with experience in consulting sexual violence clients, it is confirmed that the conformity of five-factor structure was found to be favorable. As a result of convergent and discriminative validity analysis, it was confirmed that the developed scale is a reasonable tool for measuring vicarious trauma of sexual violence counselors by showing proper correlation with Secondary Traumatic Stress Scale, Counselor Burnout Inventory and Inventory of Countertransference Behavior. Furthermore, as a result of correlation analysis between professional identity and Belief in a Just World, it confirmed that it has predictive validity of the scale by indicating a high negative correlation. Furthermore, the relationship between the scale of vicarious trauma of sexual violence counselors and career background was analyzed. Finally, based on the results of this study, the significance and limitations of this study and the direction of future research were discussed.

• Korean Journal of Cognitive Science
• /
• v.25 no.2
• /
• pp.159-187
• /
• 2014

Approximate number sense(hereafter, ANS) is the ability to compare and operate upon numerosity information. The numerosity comparison task is used to measure ANS. However, there is considerable variance among previous reports of ANS acuity which may be related to different task formats used. Here, we aim to investigate whether the format of the numerosity comparison task influences measurements of ANS acuity. We compared two task formats; 1) an intermixed format presenting two intermixed arrays of black and white dots, and 2) a side-by-side format showing two arrays of dots side by side. The intermixed format likely makes additional demands on general cognitive resources for inhibitory control, selective attention, or visuospatial working memory. The performance on the intermixed format was significantly lower than that of the side-by-side format resulting in an underestimation of ANS acuity compared to the expected trajectory of ANS development. In addition, the ANS acuity measured from only the side-by-side format was correlated with children's mathematical achievement and age. Our results demonstrate that measurement of ANS from the side-by-side format has higher construct and predictive validity compared to that of the intermixed format.

• Journal of the Society of Disaster Information
• /
• v.16 no.1
• /
• pp.133-143
• /
• 2020

Purpose: This study aims to derive a predictive empirical equation for PGV prediction from P-wave using earthquake records in Korea and to verify the reliability of Onsite EEW. Method: The noise of P wave is removed from the observations of 627 seismic events in Korea to derive an empirical equation with PGV on the base rock, and reliability of Onsite alarms is verified from comparing PGV's predictions and observations through simulation using the empirical equation. Result: P-waves were extracted using the Filter Picker from earthquake observation records that eliminated noises, a linear regression with PGV was used to derive a predictive empirical equation for Onsite EEW. Through the on-site warning simulation we could get a success rate of 80% within the MMI±1 error range above MMI IV or higher. Conclusion: Through this study, the design feasibility and performance of Onsite EEWS using domestic earthquake records were verified. In order to increase validity, additional medium-sized seismic observations from abroad are required, the mis-detection of P waves is controlled, and the effect of seismic amplification on the surface is required.

• Journal of the Korean Society of Radiology
• /
• v.13 no.1
• /
• pp.9-14
• /
• 2019

This study aimed to investigate the performance of the S-detect method in breast ultrasonography and to determine how to reduce unnecessary biopsy by comparing the results of the S-detect method and biopsy. Thirty patients who had undergone breast ultrasonography between August and October 2018 and were scheduled to undergo biopsy because of the presence of breast nodules were retrospectively analyzed. The McNemar test was performed to determine whether detection of a malignant breast mass significantly differed between the S-detect method and biopsy. The following results were obtained from the analysis of the S-detect method: sensitivity, 90.9%; specificity, 84.21%; validity, 86.66%; positive predictive value, 76.92%; and negative predictive value, 94.11%. Analysis of the degree of agreement between the S-detect method and biopsy revealed a kappa value as high as 0.724 (p < 0.05), exhibiting good agreement between the two methods. The S-detect method in breast ultrasonography is diagnostically valuable in terms of distinguishing between malignant and benign breast masses, and if used properly before breast biopsy, unnecessary biopsy can be reduced.

• Tunnel and Underground Space
• /
• v.33 no.6
• /
• pp.594-609
• /
• 2023

TBM (Tunnel Boring Machine) method is gaining popularity in urban and underwater tunneling projects due to its ability to ensure excavation face stability and minimize environmental impact. Among the prominent models for predicting disc cutter life, the NTNU model uses the Cutter Life Index(CLI) as a key parameter, but the complexity of testing procedures and rarity of equipment make measurement challenging. In this study, CLI was predicted using multiple linear regression analysis and tree-based machine learning techniques, utilizing rock properties. Through literature review, a database including rock uniaxial compressive strength, Brazilian tensile strength, equivalent quartz content, and Cerchar abrasivity index was built, and derived variables were added. The multiple linear regression analysis selected input variables based on statistical significance and multicollinearity, while the machine learning prediction model chose variables based on their importance. Dividing the data into 80% for training and 20% for testing, a comparative analysis of the predictive performance was conducted, and XGBoost was identified as the optimal model. The validity of the multiple linear regression and XGBoost models derived in this study was confirmed by comparing their predictive performance with prior research.

• Korean Journal of Radiology
• /
• v.20 no.5
• /
• pp.719-728
• /
• 2019

Objective: To investigate the diagnostic validity of coronary computed tomography angiography (cCTA) in vasospastic angina (VA) and factors associated with discrepant results between invasive coronary angiography with the ergonovine provocation test (iCAG-EPT) and cCTA. Materials and Methods: Of the 1397 patients diagnosed with VA from 2006 to 2016, 33 patients (75 lesions) with available cCTA data from within 6 months before iCAG-EPT were included. The severity of spasm (% diameter stenosis [%DS]) on iCAGEPT and cCTA was assessed, and the difference in %DS (Δ%DS) was calculated. Δ%DS was compared after classifying the lesions according to pre-cCTA-administered sublingual nitroglycerin (SL-NG) or beta-blockers. The lesions were further categorized with %DS ≥ 50% on iCAG-EPT or cCTA defined as a significant spasm, and the diagnostic performance of cCTA on identifying significant spasm relative to iCAG-EPT was assessed. Results: Compared to lesions without SL-NG treatment, those with SL-NG treatment showed a higher Δ%DS (39.2% vs. 22.1%, p = 0.002). However, there was no difference in Δ%DS with or without beta-blocker treatment (35.1% vs. 32.6%, p = 0.643). The significant difference in Δ%DS associated with SL-NG was more prominent in patients who were aged < 60 years, were male, had body mass index < 25 kg/m², and had no history of hypertension, diabetes, or dyslipidemia. Based on iCAG-EPT as the reference, the per-lesion-based sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of cCTA for VA diagnosis were 7.5%, 94.0%, 60.0%, 47.1%, and 48.0%, respectively. Conclusion: For patients with clinically suspected VA, confirmation with iCAG-EPT needs to be considered without completely excluding the diagnosis of VA simply based on cCTA results, although further prospective studies are required for confirmation.

• Korean Journal of Social Welfare
• /
• v.57 no.3
• /
• pp.305-335
• /
• 2005

This paper is a result from validation study for SPDA(A Screening Scale For Potential Drug-use Adolescents) created in 2003 and newly developed during 2004. SPDA aims to screen adolescents in their early stage of drug-use and to help practitioners make a preventive approach for the adolescents. 4307 junior and senior high school students were selected as primary research subjects by stratified and quota sampling methods. 305 adolescents on probation were also selected as a comparison group and asked to answer the same questionnaire. Reliability for SPDA recorded 0.914, which proved to be better than previous year's (0.898). Exploratory and confirmatory factor analyses to test construct validity proved that SPDA could be divided into 7 factors and that each factor structure of SPDA could be a proper measurement model with high level of fitness and factor loadings. Discriminant analysis to test predictive validity confirmed that SPDA could classify the adolescents excellently by the frequency of drug-use, with hit ratio of 86.6 percent(78.8% and 87.4% for junior and senior high school students respectively). For concurrent validity test, Hare Home Self-Esteem Scale, Hare School Self-Esteem, Zuckerman-Kuhlman Sensation-seeking Scale were employed to find correlation with SPDA and all the three scales had significant Pearson correlation coefficients with SPDA. Known-groups validity test indicated that SPDA had an adequate power to classify out adolescents on probation from those in schooling, with a hit ratio of 71.8 percent. Cut-off point to detect adolescents with high risk of substance use was 77, which indicated approximately T score, 55 (0.5 SD), satisfying sensitivity, specificity, and efficiency criteria.

• Journal of Preventive Medicine and Public Health
• /
• v.15 no.1
• /
• pp.57-73
• /
• 1982

Questionaires on symptoms of respiratory disease have been used in Korea to elicit the probable health effects of air pollution in epidemiologic studies: The objectives of such studies often include comparing prevalence of symptoms of respiratory system between different population groups or between the same population groups, at different times. Unfortunately, little attention has, been paid to standardization of those questionaires, whether those are Korean. versions or not. Furthermore, no attempt to develop Korean ,questionaire on respiratory symptoms and relevant information has been made. Followed by 'a comparative study on responses to Korean version questionaires(English origin) of CMI, MRC, and ATS-DLD-78' two types of questionaires on respiratory symptoms and relevant information for Korean adult, which are short form (SUN-81-AS) and long forms (optional questions are added to the short one, SUN-81-AL), have been designed suitable to Korean background by authors (see Annex). The self-administered and closed-question questionaire were tested their validity and reliability by administration to l80 normal adults (medical and nursing students) and 60 clinical patients of Seoul National University Hospital, with spirometric exam. The results obtained and conclusions drawn are as follow: 1. It took less than 10 minutes to complete the questionaire SNU-81-AS and SNU-81-AL. 2. The test-retest reliability of each questions in AS and AL ,were observed as 92.7% and 92.1%, respectively. And all of the level of agreement are statistically significant with kappa statistic. 3. In addition to higher prevalence rate of symptoms in patients group compared, with, normal. group, the correlations between FEV 1.0/FVC predictive value(%) and number of symptoms were statistically significant inpatients group (See Fig. 1 and, Table 7). 4. The answer rate to optional questions in AL form among those who are not to do was about 10%, while the no-answer rate among who are to do was about 15% in Normal (medical and nursing students) group. 5. From the viewpoints of validity and reliability, the new Korean questionaire (SNU-81-AS and AL) developed by authors are to be recommendable to use in epidemiologic studies on respiratory illness in Korea. The self-administration, however, of optional questions in AL form may not assure the quality of data gathered.