• 응용통계연구
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• 제25권5호
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• pp.719-731
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• 2012

Agreement analysis is conducted to assess reliability among rating results performed repeatedly on the same subjects by one or more raters. The kappa statistic is commonly used when rating scales are categorical. The simple and weighted kappa statistics are used to measure the degree of agreement between two raters, and the generalized kappa statistics to measure the degree of agreement among more than two raters. In this paper, we compare the performance of four different generalized kappa statistics proposed by Fleiss (1971), Conger (1980), Randolph (2005), and Gwet (2008a). We also examine how sensitive each of four generalized kappa statistics can be to the marginal probability distribution as to whether marginal balancedness and/or homogeneity hold or not. The performance of the four methods is compared in terms of the relative bias and coverage rate through simulation studies in various scenarios with different numbers of raters, subjects, and categories. A real data example is also presented to illustrate the four methods.

• 한방안이비인후피부과학회지
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• 제30권4호
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• pp.97-103
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• 2017

Objectives : To identify whether pattern identification using nasal endoscopy for rhinitis can be applied as a tool for evaluating rhinitis in routine care setting, we performed a inter-rater reliability study on this pattern identification. Methods : Two Korean medicine doctors assessed 290 left/right nasal endoscopy photograph cases of rhinitis patients with pattern identification using nasal endoscopy. This pattern identification consist of four assessment items, nasal membrane color(pale/hyperemia), nasal membrane humidity(dryness/dampness), rhinorrhea(watery/yellow), and turbinate membrane edema(atrophic/edematous). Cohen's kappa statistic and Percentage agreement were used to evaluate the inter-rater reliability. Results : Inter-rater percentage agreement and Kappa coefficient for left nasal endoscopy photograph cases was from 'slight' to 'moderate'(% agreement: 40.00-67.59%/Kappa: 0.06-0.407). Only the agreement of 'rhinorrhea (watery/yellow)' item was moderate(% agreement: 67.59%/Kappa: 0.407). Inter-rater percentage agreement and Kappa coefficient for right nasal endoscopy photograph cases was also from 'slight' to 'moderate'(% agreement: 42.41-68.97%/Kappa: 0.109-0.465). Only the agreement of 'rhinorrhea(watery/yellow)' item was moderate(% agreement: 68.97%/Kappa: 0.465). Conclusions : It is necessary to resolve problems such as cut-off value setting, bipolar evaluation values(pale/hyperemia, dryness/dampness, watery/yellow, atrophic/edematous) and weighting items. Further rigorous studies that overcome the limitations of the current research are warranted.

• Journal of Preventive Medicine and Public Health
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• 제43권1호
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• pp.9-17
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• 2010

Objectives: Parkinson's disease is one of the most common neurodegenerative diseases in the elderly population. In order to estimate the prevalence of Parkinson's disease in the community, the application of a good screening tool is essential. We evaluated the validity and reliability of a Parkinson's disease screening questionnaire and propose an alternative measure to improve its validity for use in community surveys. Methods: We designed the study in a three-phase approach consisting of a screening questionnaire, neurologic examination, and confirmatory examination. A repeated survey was administered to patients with disease detected in the community and on 150 subjects. We examined internal consistency using Cronbach's alpha test, test-retest reliability using the kappa statistic, and validity using sensitivity, specificity, and ROC curves. Unadjusted odds ratios were utilized for the estimation of weights for each questionnaire item. Results: The Cronbach's alpha of the questionnaire was 0.708. The kappa statistic for test-retest reliability was good to generally fair in most of the items. When newly proposed weighting scores were used, the optimum cut-off value was 7/8. When cut-off value was 5/6 for surveying prevalence in a community, the sensitivity was 0.98, and the specificity was 0.61, with simultaneous improvement in reliability. Conclusions: We recommend 5/6 as the ideal cut-off value for the survey of PD prevalence in community. This questionnaire designed for the Korean community could help future epidemiologic studies of PD.

• Journal of Korean Neurosurgical Society
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• 제30권sup2호
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• pp.254-258
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• 2001

Objective : The terminology of degenerative disc disease lacks official standardization. Lacks of such standardization may provoke some clinical and litigation problems. The authors investigated interobserver and intraobserver variability in interpretation of lumbar disc abnormality. Methods : Magnetic resonance imaging studies of the lumbar spine performed prospectively in 50 patients, were read blindly by three doctors dealing spinal disorders, using two nomenclature. Nomenclature I was normal, bulging, protrusion, extrusion. Nomenclature II was normal, bulging, herniation without neural compression, with neural compression. Intraobserver and interobserver variation were measured statistically. Results : Interobserver agreement was 70.4-80.8% for nomenclature I, 76.2-80.2% for nomenclature II. Intraobserver agreement was 84.0-88.0% for nomenclature I, 79.2-86.8% for nomenclature II. Interobserver Kappa statistic was 0.53-0.56 for nomenclature I, 0.54-0.57 for nomenclature II. Intraobserver Kappa statistic was 0.60-0.85 for nomenclature I, 0.53-0.72 for nomenclature II. Conclusion : Experienced doctors showed only moderate interobserver agreement when interpreting disc status on lumbar magnetic resonance imaging. Intraobserver agreement was superior to interbserver. The standardization of nomenclatures for lumbar disc extension beyond interspace are needed.

• 응용통계연구
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• 제10권1호
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• pp.189-201
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• 1997

반복측정된 자료에 있어 어떤 특성이 시간의 경과에 따라서 계속적으로 일정수준을 유지할 경우 지속성 현상이 있다고 한다. 만성질환의 위험요인이 지속성 현상을 갖는다면 조기에 위험요인에 대한 처치를 통하여 만성질환을 예방할 수 있으므로 역학 연구에서 지속성을 규명하는 것은 매우 중요하다. 본 연구에서는 지속성을 전체 관찰시점을 통한 일치도 및 시간의 경과에 따른 유지도를 정의하고 반복측정된 자료로부터 지속성 현상을 설명할 수 있는 새로운 지속성 지수를 제안하였다. 모의실험을 통하여 제안통계량과 지속성 지수로 널리 이용되는 McMahan의 지수를 비교하여 본고에서 제안한 지수가 더 높은 검정력을 나타내고 있는 것을 관찰하였다. 또한 제안통계량을 실제 자료에 적용해 본 결과, 제안통계량은 지속성 현상을 적절하게 설명함을 보았다.

• 기본간호학회지
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• 제24권3호
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• pp.189-199
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• 2017

Purpose: This study was conducted to examine the level of agreement between a standardized patient (SP) and a faculty member in the evaluation of nursing students' assessment and communication skills. Methods: Participants were 51 third year nursing students in a simulation practice of 'nursing care for a patient admitted with chest pain'. Using a 30-item checklist and a 16-item communication tool, a SP and faculty member evaluated the students' assessment and communication skills during the simulation. Results: The average values for percent agreement and kappa statistic for nursing assessment between the two evaluators were 85.3% and .48 respectively. Twenty of thirty items evaluating assessment skill had above moderate agreement (${\geq}.41$) by kappa between the evaluators. Seven of sixteen items evaluating communication and interpersonal skills showed above fair agreement (${\geq}.40$) between the two evaluators, which was measured by intraclass correlation coefficient. Conclusion: The findings show that the evaluation of the SP was consistent with those of the faculty member to a moderate degree. Clear guidelines for evaluating criteria and optimal time and effort for SP training are necessary to increase the reliability of standardized patients as evaluators in simulation-based nursing education.

• Ocean and Polar Research
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• 제34권2호
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• pp.265-273
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• 2012

A new algorithm was developed, not only to detect the existence of a thermocline, but also to extract the thermocline parameters (such as thermocline thickness, mixed layer thickness, maximum temperature gradient, and temperature difference of thermocline), using the vertical profile of water temperature. According to Kappa analysis, in order to find adequate threshold values of vertical water temperature gradients ${\Delta}T$ ($^{\circ}C/m$), agreement and reliability were 87% and 0.74 respectively, in the conditions of maximum ${\Delta}T{\geq}0.5$ and surface and bottom layers ${\Delta}T<{\mid}0.2{\mid}$. Also, three different kinds of methods, viz. 1. Gradient method, 2. Hyperbolic tangent method, and 3. Differential hyperbolic tangent method, were tested to extract the key parameters of a thermocline. Comparing the results of three different methods, the differential hyperbolic tangent method was the most appropriate to extract the start and end point of a thermocline curve.

• Journal of Korean Neurosurgical Society
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• 제47권2호
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• pp.89-94
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• 2010

Objective : To evaluate the role of cranial sonography and computed tomography in the diagnosis of neonatal intracranial hemorrhage and hypoxic-ischemic injury in an Indian set-up. Methods : The study included 100 neonates who underwent cranial sonography and computed tomography (CT) in the first month of life for suspected intracranial ischemia and hemorrhage. Two observers rated the images for possible intracranial lesions and a kappa statistic for interobserver agreement was calculated. Results : There was no significant difference in the kappa values of CT and ultrasonography (USG) for the diagnosis of germinal matrix hemorrhage/intraventricular hemorrhage (GMH/IVH) and periventricular leucomalacia (PVL) and both showed good interobserver agreement. USG, however detected more cases of GMH/IVH (24 cases) and PVL (19) cases than CT (22 cases and 16 cases of IVH and PVL, respectively). CT had significantly better interobserver agreement for the diagnosis of hypoxic ischemic injury (HII) in term infants and also detected more cases (33) as compared to USG (18). CT also detected 6 cases of extraaxial hemorrhages as compared to 1 detected by USG. Conclusion : USG is better modality for imaging preterm neonates with suspected IVH or PVL. However, USG is unreliable in the imaging of term newborns with suspected HII where CT or magnetic resonance image scan is a better modality.

• 대한소아치과학회지
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• 제42권3호
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• pp.209-217
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• 2015

본 연구는 Q-ray view (All in one Bio, Seoul, Korea)가 변연융선이 파괴되지 않은 유구치의 인접면 우식증을 적절히 탐지해 낼 수 있는지 알아보고자 하였다. 두 명의 소아치과의사가 3-9세 사이의 어린이 32명(평균연령 $5.6{\pm}1.3$세)의 유구치 인접면 100개를 시진, Q-ray view, DIAGNOdent (KaVo, Biberach, Germany), 디지털 치근단 방사선사진 촬영으로 평가하였다. 각 검사법과 실제 치료 시 관찰된 인접면 우식증의 진행 정도를 비교하였을 때, 법랑질 우식증에 대한 kappa값은 시진, Q-ray view, DIAGNOdent, 디지털 치근단 방사선사진 촬영 순으로 0.15, 0.10, 0.25, 0.68이었으며, 상아질 우식증에 대한 kappa값은 0.34, 0.56, 0.44, 0.70이었다. Q-ray view는 상아질까지 진행된 유구치의 숨은 인접면 우식증을 탐지하는 데 도움을 줄 수 있는 유용하고 간편한 보조장비가 될 수 있을 것으로 기대된다.

• 응용통계연구
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• 제7권2호
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• pp.159-171
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• 1994

본 논문에서는 $\kappa$-표본 문제에서 우산형 위치-척도 대립가설에 대한 순위검정법들을 연구하였다. 위치모수와 척도모수의 변동에 민감한 순위점수에 기초한 검정통계량들을 제안하였다. 우산형 대립가설의 정점이 알려진 경우를 다루었으며 귀무가설과 대립가설하에서의 점근성질도 아울러 조사되었다. 모수들간의 간격이 같지않는 우산형 위치-척도모형에서 Chen-Wolfe의 동위회귀 추정량을 이용한 순위통계량에 의존한 검정법이 효율적이었으며 또한 아주 안정적이었다.