1.Using the Receiver Operating Characteristic (ROC) Curve to Measure Sensitivity and Specificity.
Korean Journal of Family Medicine 2009;30(11):841-842
No abstract available.
ROC Curve
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Sensitivity and Specificity*
2.Differential LINE-1 Hypomethylation of Gastric Low-Grade Dysplasia from High Grade Dysplasia and Intramucosal Cancer.
Jeong Rok LEE ; Woo Chul CHUNG ; Jin Dong KIM ; Kang Moon LEE ; Chang Nyol PAIK ; Sung Hoon JUNG ; Ji Han JUNG ; Yun Kyung LEE ; Sok Won HAN
Gut and Liver 2011;5(2):149-153
BACKGROUND/AIMS: Gastric epithelial dysplasia is considered a precancerous lesion with a variable clinical course. There is disagreement, however, regarding histology-based diagnoses, which has led to confusion in choosing a therapeutic plan. New objective markers are needed to determine which lesions progress to true malignancy. We measured LINE-1 methylation levels, which have been reported to strongly correlate with the global methylation level in gastric epithelial dysplasia and intramucosal cancer. METHODS: A total of 145 tissue samples were analyzed by two histopathologists. All tissues were excised by therapeutic endoscopic mucosal resection and paired with adjacent normal tissue samples. A modified long interspersed nucleotide elements-combined bisulfite restriction analysis (COBRA-LINE-1) method was used. RESULTS: Gastric epithelial dysplasia and intramucosal cancer tissues had significantly lower levels of LINE-1 methylation than adjacent normal gastric tissues. High-grade dysplasia and intramucosal cancer were distinguishable from low-grade dysplasia based on LINE-1 methylation levels. Furthermore, the distinction could be determined with high sensitivity and specificity, as shown by the receiver operating characteristic (ROC) curve (AUC, 0.82; 95% confidence interval, 0.74 to 0.88). CONCLUSIONS: LINE-1 methylation levels may provide a diagnostic tool for identifying high-grade dysplasia and intramucosal cancer.
Methylation
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ROC Curve
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Sensitivity and Specificity
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Sulfites
3.The Ability of Disc-to-Fovea Distance to Disc-Diameter Ratio to Estimate Optic Disc Size.
Hyun Gyu YOO ; Jae Hong AHN ; Mar Vin LEE
Journal of the Korean Ophthalmological Society 2013;54(6):913-918
PURPOSE: To investigate the usefulness of the measurement of disc-to-fovea distance to disc-diameter ratio (DF/DD ratio) in detecting large and small discs. METHODS: A total of 300 randomly selected subjects were included in the present study. All patients underwent stereoscopic disc photography and DF/DD ratio, which is the shortest distance between disc margin and fovea divided by mean disc diameter was determined by planimetry. The diagnostic accuracy of DF/DD ratio was evaluated using areas under the receiver operating characteristics curves (AUCs), sensitivity, and specificity. RESULTS: No significant differences in disc-to-fovea distance were observed among small and large disc groups. The DF/DD ratio was significantly lower in subjects with large discs (1.74 +/- 0.27) compared with subjects with small discs (2.70 +/- 0.15). AUCs of the DF/DD ratio were 0.942 and 0.947 in detecting large and small discs, respectively. In detecting disc size by a fixed DF/DD ratio of 2.0, sensitivity was 100% for both large and small discs, and specificity was 70.1% and 40.9% for the large and small discs, respectively. CONCLUSIONS: The DF/DD ratio may be a simple and useful clinical aid in detecting large and small discs. The 2.0 fixed DF/DD ratio, showed 100% sensitivity in detecting both large and small discs, although medium discs may be misdiagnosed as small discs more often than as large discs.
Area Under Curve
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Humans
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Photography
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ROC Curve
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Sensitivity and Specificity
4.Impact of the Use of Contrast-Enhanced Multidetector CT for Acute Appendicitis: A Prospective Comparison with the Alvarado Score.
Mi Young CHOI ; Seong Eon YOON ; Seong Ho PARK ; Young Hwan LEE ; Shi Sung CHOI ; Seong Hoon PARK ; Seong Kwan JUHNG ; Kwon Ha YOON
Journal of the Korean Radiological Society 2007;57(6):537-544
PURPOSE: To determine the diagnostic performance of contrast-enhanced multidetector CT (MDCT) and the Alvarado score for acute appendicitis. MATERIALS AND METHODS: MDCT and determination of the Alvarado score were prospectively performed in 282 patients with 146 pathologically proven cases of acute appendicitis and 136 pathologically proven or clinically diagnosed cases of non-acute appendicitis. To compare the diagnostic performance of MDCT and the Alvarado score, the patients were subdivided according to age and sex, and receiver operating characteristics (ROC) analysis and Spearman rank correlation were performed. RESULTS: ROC analysis revealed that the optimal cut off value of the CT appendicitis grades was 2 in all patients, resulting in a sensitivity of 96.6% and a specificity of 94.9%. The optimal cut off values of the Alvarado score was different according to age and sex, resulting in a sensitivity of 85.6% and a specificity of 48.5%. There was a significant correlation between the CT appendicitis grades and the surgical-pathological grades (r=0.496, p<.0001). However, no significant correlation was observed between the Alvarado score and the surgical-pathological grades. CONCLUSION: Contrast-enhanced MDCT has a higher diagnostic accuracy and significant correlation with pathological findings than those of the Alvarado score in patients with acute appendicitis.
Acute Disease
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Appendicitis*
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Humans
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Prospective Studies*
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ROC Curve
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Sensitivity and Specificity
5.Colon Transit Time May Predict Inadequate Bowel Preparation in Patients With Chronic Constipation.
Hong Jun PARK ; Myeong Hun CHAE ; Hyun Soo KIM ; Jae Woo KIM ; Moon Young KIM ; Soon Koo BAIK ; Sang Ok KWON ; Hee Man KIM ; Kyong Joo LEE
Intestinal Research 2015;13(4):339-345
BACKGROUND/AIMS: We evaluated whether colonic transit time (CTT) can predict the degree of bowel preparation in patients with chronic constipation undergoing scheduled colonoscopy in order to assist in the development of better bowel preparation strategies for these patients. METHODS: We analyzed the records of 160 patients with chronic constipation from March 2007 to November 2012. We enrolled patients who had undergone a CTT test followed by colonoscopy. We defined patients with a CTT > or =30 hours as the slow transit time (STT) group, and patients with a CTT <30 hours as the normal transit time (NTT) group. Boston Bowel Preparation Scale (BBPS) scores were compared between the STT and NTT groups. RESULTS: Of 160 patients with chronic constipation, 82 (51%) were included in the STT group and 78 (49%) were included in the NTT group. Patients with a BBPS score of <6 were more prevalent in the STT group than in the NTT group (31.7% vs. 10.3%, P=0.001). Multivariate analysis showed that slow CTT was an independent predictor of inadequate bowel preparation (odds ratio, 0.261; 95% confidence interval, 0.107-0.634; P=0.003). The best CTT cut-off value for predicting inadequate bowel preparation in patients with chronic constipation was 37 hours, as determined by receiver operator characteristic (ROC) curve analysis (area under the ROC curve: 0.676, specificity: 0.735, sensitivity: 0.643). CONCLUSIONS: Patients with chronic constipation and a CTT >30 hours were at risk for inadequate bowel preparation. CTT measured prior to colonoscopy could be useful for developing individualized strategies for bowel preparation in patients with slow CTT, as these patients are likely to have inadequate bowel preparation.
Colon*
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Colonoscopy
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Constipation*
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Humans
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Multivariate Analysis
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ROC Curve
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Sensitivity and Specificity
6.Accuracy of maximal expiratory flow-volume curve curvilinearity and fractional exhaled nitric oxide for detection of children with atopic asthma.
Sang Hoo PARK ; Min Ji IM ; Sang Yong EOM ; Youn Soo HAHN
Korean Journal of Pediatrics 2017;60(9):290-295
PURPOSE: Airway pathology in children with atopic asthma can be reflected by the concave shape of the maximal expiratory flow-volume (MEFV) curve and high fractional exhaled nitric oxide (FeNO) values. We evaluated the capacity of the curvilinearity of the MEFV curve, FeNO, and their combination to distinguish subjects with atopic asthma from healthy individuals. METHODS: FeNO and angle β, which characterizes the general configuration of the MEFV curve, were determined in 119 steroid-naïve individuals with atopic asthma aged 8 to 16 years, and in 92 age-matched healthy controls. Receiver operating characteristic (ROC) curve analyses were performed to determine the cutoff points of FeNO and angle β that provided the best combination of sensitivity and specificity for asthma detection. RESULTS: Asthmatic patients had a significantly smaller angle β and higher FeNO compared with healthy controls (both, P<0.001). For asthma detection, the best cutoff values of angle β and FeNO were observed at 189.3° and 22 parts per billion, respectively. The area under the ROC curve for the combination of angle β and FeNO improved to 0.91 (95% confidence interval [CI], 0.87–0.95) from 0.80 (95% CI, 0.75–0.86; P<0.001) for angle β alone and 0.86 (95% CI, 0.82–0.91; P=0.002) for FeNO alone. In addition, the combination enhanced sensitivity with no significant decrease in specificity. CONCLUSION: These data suggest that the combined use of the curvilinearity of the MEFV curve and FeNO is a useful tool to differentiate between children with and without atopic asthma.
Asthma*
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Child*
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Humans
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Nitric Oxide*
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Pathology
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ROC Curve
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Sensitivity and Specificity
7.Reliability and Validity of the Korean Version of Short Blessed Test (SBT-K) as a Dementia Screening Instrument.
Dong Young LEE ; Jong Choul YOON ; Kang Uk LEE ; Jin Hyeong JHOO ; Ki Woong KIM ; Jung Hie LEE ; Jong Inn WOO
Journal of Korean Neuropsychiatric Association 1999;38(6):1365-1375
We aimed to develop the Korean version of Short Blessed test (SBT-K) by analyzing its reliability and validity, showing its usefulness as a dementia screening instrument. The translation, including back translation procedure, was carried out, keeping the basic structure of SBT. SBT-K. The Korean Version of Blessed Dementia Scale-Activity of Daily Living (BDS-ADL-K) and Clinical Dementia Rating Scale (CDR) were administered to 224 dementia patients and 191 control subjects, and The Korean Version of Consortium to Establish a Registry of Alzheimer's Disease-Mini-Mental State Examination (CERAD-MMSE-K) was to 157 patients and 167 controls. The correlation of SBT-K scores between two raters, correlation between the test and retest after one month, and its internal consistency were analyzed. To verify the concurrent validity of SBT-K, its correlation with each test: CERAD-MMSE-K, BDS-ADL-K, and CDR was analyzed. The sensitivity and specificity for each cut-off point of SBT-K were calculated and the Receiver Operator Characteristic (ROC) curve analysis was done to get its optimal cut-off point. SBT-K was found to have significantly high internal consistency, inter-rater reliability, and test-retest reliability. The significant correlation of SBT-K with each test described above was also shown. Its optimal cut-off point was estimated as 10/11, and the sensitivity and specificity were 0.85 and 0.90, respectively. The ROC curve analysis indicated that the diagnostic efficiency of SBT-K was comparable with CERAD-MMSE-K. We conclude that SBT-K has not only high reliability and validity, but also usefulness as a screening instrument for dementia.
Dementia*
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Humans
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Mass Screening*
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Reproducibility of Results*
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ROC Curve
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Sensitivity and Specificity
8.Glaucoma Discrimination by Combined Use of Frequency Doubling Technology and Heidelberg Retina Tomography II.
Journal of the Korean Ophthalmological Society 2005;46(2):306-315
PURPOSE: This study investigated whether the combined use of Frequency Doubling Technology and Heidelberg Retina Tomography II increases the usefulness of glaucoma detection. METHODS: The study subjects were, 59 patients with POAG and 34 normal persons were selected. The authors defined a total of six discriminative criteria: F1, in which the conventional analysis of FDT was used; F2, in which the FDT scoring system was used; F3, in which the Moorfield classification of HRT was used; F4, in which the new HRT discrimination function `Z' was used; F5, in which F1 and F3 were combined, and F6, in which F2 and F4 were combined; The usefulness of each criterion was investigated. RESULTS: The sensitivity, specificity, and area under the ROC curve of the six discriminative criteria were: 86.4%, 58.8%, and 0.740 in F1, 4.5%, 80.0% (cutoff: 12.50), and 0.882 in F2, 79.7%, 61.8%, and 0.679 in F3, 77.6%, 74.3% (cutoff: 0), and 0.857 in F4, 77.6%, 71.4% (cutoff: 1.0805), and 0.767 in F5, and 86.2%, 91.4% (cutoff: 0.495) and 0.931 in F6. CONCLUSIONS: Combined use of functional (FDT) and morphological (HRT) aspects, which are early parameters of glaucoma damage, gave more useful results than a single analysis of each. Thererfore, the combined use will help the early detection of glaucoma.
Classification
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Discrimination (Psychology)*
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Glaucoma*
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Humans
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Retina*
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ROC Curve
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Sensitivity and Specificity
9.The usefulness of ovarian volume using 3D VOCAL transvaginal ultrasound, antral follicle count and age as predictors of menopause in pre- and postmenopausal women.
Yoon Sook KIM ; Seob JEON ; Jong Su KIM ; Seung Do CHOI ; Jae Gun SUNWOO ; Young Woo SHIN ; Dong Han BAE
Korean Journal of Obstetrics and Gynecology 2007;50(1):167-172
OBJECTIVE: To evaluate the sensitivity and specificity of ovarian volume using 3D VOCAL and 2D ultrasound, antral follicle count, and age as predictors of menopausal status in pre- and postmenopausal women. METHODS: The subjects of this study were premenopausal (n=38) and postmenopausal (n=23) healthy women aged between 35 and 57 years of age who were interviewed about social, demographic, and medical conditions. These women underwent transvaginal ultrasound using 3D VOCAL and 2D probe to determine ovarian volume. Chi-square test was applied to evaluate the correlation between ovarian volume, antral follicle count, age and menopausal status. Receiver operating Characteristic (ROC) curves were elaborated to evaluate the sensitivity, specificity and positive and negative predictive values. RESULTS: Premenopausal women presented larger ovaries than postmenopausal women (p<0.01). Premenopausal women had a higher number of antral follicles than postmenopausal women (p<0.01). ROC curves showed that antral follicle count and ovarian volume using 3D VOCAL transvaginal probe were more sensitive and specific markers of menopausal status than age or ovarian volume using 2D transvaginal probe. CONCLUSIONS: Ovarian volume and antral follicle count differ according to age in pre- and postmenopausal women. The data suggest that antral follicle count and ovarian volume using 3D VOCAL transvaginal probe are quite useful in predicting menopausal status.
Female
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Humans
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Menopause*
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Ovary
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ROC Curve
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Sensitivity and Specificity
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Ultrasonography*
10.Role of Ultrasound Volume Measurements of Testes in Evaluation of Infertile Men with Azoospermia.
Min Hoan MOON ; Ju Tae SEO ; Yi Keong CHUN ; Chang Kyu SUNG ; Jeong Yeon CHO ; Seung Hyup KIM
Journal of the Korean Society of Medical Ultrasound 2012;31(2):87-91
PURPOSE: The purpose of our study was to assess the usefulness of ultrasounddetermined testicular volume in the evaluation of the infertile men with azoospermia. MATERIALS AND METHODS: A computerized search from October 2005 to June 2010 generated a list of 45 infertile men with azoospermia (mean age, 34 years; age range, 26-44 years) who underwent both scrotal ultrasound and testis biopsy. Ultrasounddetermined testicular volumes were compared between infertile men with obstructive azoospermia and those with non-obstructive azoospermia. RESULTS: Testicular volume for obstructive azoospermia ranged from 6.4 ml to 26.9 ml, with a median volume of 14.0 ml. This volume was significantly larger than that of those with non-obstructive azoospermia, which ranged from 1.0 ml to 12.8 ml, with a median volume of 6.1 ml (p < 0.001). The area under the ROC curve for distinguishing non-obstructive azoospermia from obstructive azoospermia using testicular volume was 0.91. A cutoff value of less than or equal to 11.4 ml could distinguish non-obstructive azoospermia from obstructive azoospermia, with a sensitivity of 94.1% (95% CI; 71.3-99.9%) and a specificity of 73.3% (95% CI; 54.1-87.7%). CONCLUSION: Ultrasound-determined testicular volume can be helpful in the differentiation of obstructive azoospermia from non-obstructive azoospermia.
Azoospermia
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Biopsy
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Humans
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Male
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ROC Curve
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Sensitivity and Specificity
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Testis