• 제목/요약/키워드: Kappa index

검색결과 155건 처리시간 0.024초

인공호흡기 사용 환자들에게 제공된 예비적 정보에 대한 내용분석의 측정자간 신뢰도 (Interrater Reliability in the Content Analysis of Preparatory Information for Mechanically Ventilated Patients)

  • 김화순
    • 기본간호학회지
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    • 제5권2호
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    • pp.269-279
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    • 1998
  • In nursing research that the data is collected through clinical observation, analysis of clinical recording or coding of interpersonal interaction in clinical areas, testing and reporting interrater reliability is very important to assure reliable results. Procedures for interrater reliability in these studies should follow two steps. The first step is to determine unitizing reliability, which is defined as consistency in the identification of same data elements in the record by two or more raters reviewing the same record. Unitizing reliability have been rarely reported in previous studies. Unitizing reliability should be tested before progressing to the next step as precondition. Next step is to determine interpretive reliability. Cohen's kappa is a preferable method of calculating the extent of agreement between observer or judges because it provides beyond-chance agreement. Despite its usefulness, kappa can sometimes present paradoxical conclusions and can be difficult to interpret. These difficulties result from the feature of kappa which is affected in complex ways by the presence of bias between observers and by true prevalence of certain categories. Therefore, percentage agreement should be reported with kappa for adequate interpretation of kappa. The presence of bias should be assessed using the bias index and the effect of prevalence should be assessed using the prevalence index. Researchers have been reported only global reliability reflecting the extent to which coders can consistently use the whole coding system across all categories. Category-by-category reliability also need to be reported to inform the possibility that some categories are harder to use than others.

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심박동수 및 관상동맥 석회화가 64 절편 다중검출기 심장 CT의 관상동맥 질환 진단일치도에 미치는 영향 (The Influence of Heart Rate and Coronary Calcification on the Diagnostic Accuracy of 64-slice Multidetector Cardiac CT in Coronary Artery Disease)

  • 강영한;박종삼
    • 한국콘텐츠학회논문지
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    • 제9권12호
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    • pp.339-347
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    • 2009
  • 연구목적: 64 절편 MDCT를 이용한 심장 CT의 진단일치도를 알아보고, 심박동수와 관상동맥 석회화가 진단일치도에 영향을 미치는지 확인하여 심장 CT 검사 시 기초 자료로 활용하고자 함이다. 연구방법: 심장 CT와 관상동맥 조영술을 함께 시행한 178명(남자 84명, 여자 94명)을 대상으로 심장 CT에서 관상동맥 협착과 심박동수, 석회화 수치를 측정하였고, 관상동맥조영술에서 좌전하행동맥, 좌회선동맥, 우관상동맥의 유의한 협착($\geq50%$)이 있는지 확인하였다. 관상동맥 조영술의 결과를 표준으로 심장 CT의 민감도, 특이도, 양성예측도, 음성예측도, kappa index($\kappa$)를 계산하였다. 연구결과: 환자별 협착의 정도를 평가한 결과 심장 CT의 정확도는 96.6%였다. 혈관별로는 LAD, LCX, RCA 각각 86.5%, 84.3%, 92.1%로 높은 진단일치도를 보였다. 체질량지수와 혈압은 심장 CT의 진단일치도에 영향을 미치지 않았다. 심박동수는 60/min 미만에서 정확도 90.1%, $\kappa$값 0.78이었고, 70/min 이상에서는 정확도가 75.8%, $\kappa$값 0.52이었다. 관상동맥 석회화지수 100 미만에서는 정확도가 91.3%, $\kappa$값 0.81이었고, 석회화지수 400 이상에서는 정확도 68.6%, $\kappa$값 0.33으로 떨어졌다. 결론: 64 절편 MDCT를 이용한 심장 CT는 관상동맥 조영술과 거의 비슷한 진단일치도를 나타냈다. 하지만 심박동수 70/min 이상, 관상동맥 석회화지수 400 이상에서는 진단일치도가 저하되었기 때문에 심장 CT 검사 시 심박동수와 관상동맥 석회화지수를 확인하여 검사하여야 하고, 심박동수가 70/min 이상이면 베타차단제를 사용하여 심박동수를 조절하여야 한다.

위암 수술 환자의 건강결과 측정을 위한 동반상병 측정도구의 유용성 연구 (Usefulness of Comorbidity Indices in Operative Gastric Cancer Cases)

  • 황세민;윤석준;안형식;안형진;김상후;경민호;이은경
    • Journal of Preventive Medicine and Public Health
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    • 제42권1호
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    • pp.49-58
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    • 2009
  • Objectives : The purpose of the current study was to evaluate the usefulness of the following four comorbidity indices in gastric cancer patients who underwent surgery: Charlson Comorbidity Index(CCI), Cumulative Illness rating scale(CIRS), Index of Co-existent Disease(ICED), and Kaplan-Feinstein Scale(KFS). Methods : The study subjects were 614 adults who underwent surgery for gastric cancer at K hospital between 2005 and 2007. We examined the test-retest and inter-rater reliability of 4 comorbidity indices for 50 patients. Reliability was evaluated with Spearman rho coefficients for CCI and CIRS, while Kappa values were used for the ICED and KFS indices. Logistic regression was used to determine how these comorbidity indices affected unplanned readmission and death. Multiple regression was used for determining if the comorbidity indices affected length of stay and hospital costs. Results : The test-retest reliability of CCI and CIRS was substantial(Spearman rho=0.746 and 0.775, respectively), while for ICED and KFS was moderate(Kappa=0.476 and 0.504, respectively). The inter-rater reliability of the CCI, CIRS, and ICED was moderate(Spearman rho=0.580 and 0.668, and Kappa=0.433, respectively), but for KFS was fair(Kappa=0.383). According to the results from logistic regression, unplanned readmissions and deaths were not significantly different between the comorbidity index scores. But, according to the results from multiple linear regression, the CIRS group showed a significantly increased length of hospital stay(p<0.01). Additionally, CCI showed a significant association with increased hospital costs (p<0.01). Conclusions : This study suggests that the CCI index may be useful in the estimation of comorbidities associated with hospital costs, while the CIRS index may be useful where estimatation of comorbiditie associated with the length of hospital stay are concerned.

Development and validation of a novel screening instrument to prioritize the orthodontic referral of developing malocclusion in children: The index for interceptive orthodontics referral

  • Saraswathy Devi Sinniah;Annapurny Venkiteswaran;Najiyatu Nazihah Zakaria
    • 대한치과교정학회지
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    • 제53권2호
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    • pp.116-124
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    • 2023
  • Objective: The absence of a guideline to refer to developing malocclusions appropriately, may be a contributing factor to the inadequacy of timely interceptive orthodontics provision. This study aimed to develop and validate a new orthodontic grading and referral index to be used by dental frontliners to prioritize the orthodontic referral of developing malocclusion in children based on its severity. Methods: A cross-sectional study involving clinical assessment with 413 schoolchildren aged between 8.1 and 11.9 years was conducted in 2018. All the presenting malocclusion was listed and graded based on a few dental guidelines to produce the draft index. The validity and reliability of the draft index were tested using twenty study models. Face and content validation was carried out using the content validation index and Modified Kappa Statistics. Results: Fourteen dental and occlusal anomalies were identified as components of malocclusion and three grades of referral (monitor, standard, urgent) were included in the final index. The scale-level content validity index average value of 0.86 and 0.87 was obtained for content and face validation, respectively. There was moderate to excellent agreement in the Modified Kappa Statistics for both validations. Excellent inter- and intra-assessor agreement was obtained. The new index displayed valid and reliable scores. Conclusions: The Index for Interceptive Orthodontics Referral was developed and validated for the dental frontliners to identify and prioritize the developing malocclusion in children based on its severity and refer for orthodontic consultation to increase the possibility for interceptive orthodontics.

고수율 및 저카파가의 볏짚화학펄프 제조방법 개발 (Development of Pulping Methods of Rice-straw Chemical Pulp with Higher Yield and Lower Kappa Number)

  • 강진하;박성종
    • 펄프종이기술
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    • 제32권2호
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    • pp.58-67
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    • 2000
  • This study was carried out to acquire basic data necessary for the use of non-wood pulp. Various chemical pulping methods for rice straw to achieve higher yield, lower Kappa No. were investigated and then the physical properties of various pulps were tested. The results of this study were as follows: When various chemical pulps (Soda, Soda-AQ, Soda-$H_2O_2$, Soda-$Na_2S_2$, AS, AS-AQ, AS-$Na_2S_2O_3$, AS-$Na_2S_2O_4$, Kraft) were produced with rice-straw, the pulps with the highest yield and lowest Kappa No. were obtained with Soda-$Na_2S_2$and AS-$Na_2S_2O_4$pulps. For the breaking length, Soda and Soda-additive pulps(7.5~9.2km) were better than AS and AS-additive pulps(6.2~8.1km). Similarly, for the burst index, Soda and Soda-additive pulps(6.0~7.0 kPa.$m^2$/g) were better than AS and AS-additive pulps(4.5~6.3 kPa.m$^2$/g). But the tear index was showed 21.8-30.9 mN.$m^2$/g with a little different between pulping methods.

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실제 착색된 치면세균막 면적과 전통적인 치면세균막 지수 비교 (Comparison of traditional dental plaque indices with real stained plaque area)

  • 김지수;양용훈;전은주;김진범;정승화
    • Journal of Korean Academy of Oral Health
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    • 제41권4호
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    • pp.262-266
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    • 2017
  • Objectives: The aim of this study was to compare Plaque Percent Index (PPI), calculated by Patient Hygiene Performance Index (PHPI), Rustogi's modification of the Navy Plaque Index (RMNPI), and the Quigley & Hein Plaque Index (QHPI), with visual assessment. Methods: Ninety-six subjects, aged between 30-65 years, were examined; twenty subjects were included in the final analysis. The subjects' teeth were stained and photographed. Dental coloring and intraoral camera photography were performed by a single examiner. The oral images obtained were analyzed using Image J to measure the area of dental plaque. The values of PHPI, RMNPI, and QHPI were calculated twice. Statistical analyses were performed using descriptive statistics, chi-square test, and Pearson's correlation coefficient. Results: The results of the correlation analyses of PPI with PHPI, QHPI, and RMNPI were as follows: for PHPI, the correlation coefficient (r)=0.584; for QHPI, r=0.689; and for RMNPI, r=0.729. Further, the kappa indices of PHPI, QHPI, and RMNPI were 0.810, 0.677, and 0.590 respectively. Conclusions: Among RMNPI, QHPI, and PHPI dental plaque indices, RMNPI and QHPI showed a high degree of correlation with the actual stained dental plaque area; on the other hand, PHPI showed the highest kappa index.

Comparative Analysis of Supervised and Phenology-Based Approaches for Crop Mapping: A Case Study in South Korea

  • Ehsan Rahimi;Chuleui Jung
    • 대한원격탐사학회지
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    • 제40권2호
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    • pp.179-190
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    • 2024
  • This study aims to compare supervised classification methods with phenology-based approaches, specifically pixel-based and segment-based methods, for accurate crop mapping in agricultural landscapes. We utilized Sentinel-2A imagery, which provides multispectral data for accurate crop mapping. 31 normalized difference vegetation index (NDVI) images were calculated from the Sentinel-2A data. Next, we employed phenology-based approaches to extract valuable information from the NDVI time series. A set of 10 phenology metrics was extracted from the NDVI data. For the supervised classification, we employed the maximum likelihood (MaxLike) algorithm. For the phenology-based approaches, we implemented both pixel-based and segment-based methods. The results indicate that phenology-based approaches outperformed the MaxLike algorithm in regions with frequent rainfall and cloudy conditions. The segment-based phenology approach demonstrated the highest kappa coefficient of 0.85, indicating a high level of agreement with the ground truth data. The pixel-based phenology approach also achieved a commendable kappa coefficient of 0.81, indicating its effectiveness in accurately classifying the crop types. On the other hand, the supervised classification method (MaxLike) yielded a lower kappa coefficient of 0.74. Our study suggests that segment-based phenology mapping is a suitable approach for regions like South Korea, where continuous cloud-free satellite images are scarce. However, establishing precise classification thresholds remains challenging due to the lack of adequately sampled NDVI data. Despite this limitation, the phenology-based approach demonstrates its potential in crop classification, particularly in regions with varying weather patterns.

Heaviness of Smoking Index, Number of Cigarettes Smoked and the Fagerstrom Test for Nicotine Dependence Among Adult Male Malaysians

  • Lim, K.H.;Idzwan, M. Feisul;Sumarni, M.G.;Kee, C.C.;Amal, N.M.;Lim, K.K.;Gurpreet, K.
    • Asian Pacific Journal of Cancer Prevention
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    • 제13권1호
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    • pp.343-346
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    • 2012
  • Two methods of identifying smokers with high nicotine dependence, the heaviness of smoking index (HSI) and number of cigarettes per day (CPD) were compared with the Fagerstrom test for nicotine dependence (FTND). The HSI, CPD and the FTND were administered to 316 adult Malaysian male, daily smokers aged between 25-64 years old in the Malaysian NCD Surveillance-1 Survey using a two-stage stratified random sampling of enumeration blocks and living quarters, via an interview based on a validated questionnaire. The cut-off point for classification of high nicotine dependence on the HSI was a score of four or higher, and for the heavy smoking category, smoking more than 20 cigarettes per day. Classification using each method was compared with classification by the FTND (score of six or more) as the reference standard. Sensitivity, specificity and kappa statistics for concordance between both measures and the FTND were evaluated. The HSI gave a similar prevalence rate of high nicotine dependence as the FTND. There was substantial agreement between the HSI and the FTND (kappa=0.63.), with moderate sensitivity (69.8%) and high specificity (92.5%). However, prevalence of high nicotine dependence using the CPD was 7% lower than the FTND. The heavy smoking category also showed fair agreement with the FTND (kappa=0.45) and moderate sensitivity (67.0%), but specificity was high (86.9%). The findings indicate that the HSI can be used as an alternative to the FTND in screening for high nicotine dependence among daily smokers in large population-based studies, while CPD may not be a suitable alternative to the FTND.

MMPI 분석도구로서 인공신경망 분석과 로지스틱 회귀분석의 비교 (Comparison between Logistic Regression and Artificial Neural Networks as MMPI Discriminator)

  • 이재원;정범석;김미숙;최지욱;안병은
    • 생물정신의학
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    • 제12권2호
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    • pp.165-172
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    • 2005
  • Objectives:The purpose of this study is to 1) conduct a discrimination analysis of schizophrenia and bipolar affective disorder using MMPI profile through artificial neural network analysis and logistic regression analysis, 2) to make a comparison between advantages and disadvantages of the two methods, and 3) to demonstrate the usefulness of artificial neural network analysis of psychiatric data. Procedure:The MMPI profiles for 181 schizophrenia and bipolar affective disorder patients were selected. Of these profiles, 50 were randomly placed in the learning group and the remaining 131 were placed in the validation group. The artificial neural network was trained using the profiles of the learning group and the 131 profiles of the validation group were analyzed. A logistic regression analysis was then conducted in a similar manner. The results of the two analyses were compared and contrasted using sensitivity, specificity, ROC curves, and kappa index. Results:Logistic regression analysis and artificial neural network analysis both exhibited satisfactory discriminating ability at Kappa index of greater than 0.4. The comparison of the two methods revealed artificial neural network analysis is superior to logistic regression analysis in its discriminating capacity, displaying higher values of Kappa index, specificity, and AUC(Area Under the Curve) of ROC curve than those of logistic regression analysis. Conclusion:Artificial neural network analysis is a new tool whose frequency of use has been increasing for its superiority in nonlinear applications. However, it does possess insufficiencies such as difficulties in understanding the relationship between dependent and independent variables. Nevertheless, when used in conjunction with other analysis tools which supplement it, such as the logistic regression analysis, it may serve as a powerful tool for psychiatric data analysis.

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위성영상 해상도에 따른 순천만 해안습지의 분류 정확도 변화 (The change of land cover classification accuracies according to spatial resolution in case of Sunchon bay coastal wetland)

  • 구자용;황철수
    • 한국지역지리학회지
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    • 제7권1호
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    • pp.35-50
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    • 2001
  • 공간상의 지리현상은 축척에 따라 공간적 분포패턴이 다르게 표현되고 측정될 수 있다. 특정한 지리현상은 특정한 축척에서 보다 선명하게 관찰될 수 있다. 지표면의 정보를 담고 있는 위성영상 역시 공간해상도의 영향에 의해 독특한 특성을 보이고 있다. 위성영상의 분석을 위한 적정해상도를 모색하기 위해서는 영상으로부터 분류되는 속성의 특성을 파악하여야 한다. 본 연구에서는 순천만 해안습지를 대상으로 위성영상으로부터 토지피복 정보를 추출하고, 공간 해상도의 변화에 따른 변화를 살펴보았다. 순천만 영상을 대상으로 토지피복 분류정확도를 파악한 후 30m 해상도부터 480m 해상도까지 30m 간격의 16가지 해상도로 영상을 제작하여 분류정확도의 변화를 살펴보았다. 순천만 해안습지는 다양한 토지유형이 다양한 크기로 분포하고 있어 해상도의 변화에 따라 토지피복 특성이 변화하고 있으며, 순천만의 위성영상 역시 축척 효과에 의해 해상도에 따라 속성정보의 특성의 변화가 뚜렷하게 나타난다.

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