• Title/Summary/Keyword: Intraclass Correlation Coefficient

Search Result 220, Processing Time 0.032 seconds

A reliability measure of three dimensional shapes based on statistical shape analysis (통계적 형상분석을 이용한 3차원 형상의 신뢰도 계수)

  • Shin, Sang Min
    • The Korean Journal of Applied Statistics
    • /
    • v.32 no.1
    • /
    • pp.15-27
    • /
    • 2019
  • The reliability of the data means the overall consistency of the measurement results. Methods for evaluating reliability have been continuously studied because it affects the results of the statistical analysis. Cronbach's ${\alpha}$ coefficient or intraclass correlation coefficient is used for reliability evaluation; however, these measures cannot be applied to data consisting of three-dimensional coordinates to represent an object. In this study, we propose a measure to evaluate the reliability of three dimensional shapes based on statistical shape analysis that is made possible by extracting the shape information from the measured three dimensional coordinates and decomposing the shape variation.

Development and Verification of a Simultaneous Analytical Method for Whole Blood Metals and Metalloids for Biomonitoring Programs (바이오모니터링 프로그램을 위한 혈중 금속류 동시분석법 개발 및 확인 평가)

  • Cha, Sangwon;Oh, Eunha;Oh, Selim;Han, Sang Beom;Im, Hosub
    • Journal of Environmental Health Sciences
    • /
    • v.47 no.1
    • /
    • pp.64-77
    • /
    • 2021
  • Objective: Biological monitoring of trace elements in human blood samples has become an important indicator of the health environment. The purpose of this study was to detect and evaluate multiple metal items in blood samples based on ICP-MS, to perform comparative evaluation with the existing analysis method, and to develop and verify a new method. Methods: 100 μL of whole blood from 80 healthy subjects was used to analyze ten metals (Sb, tAs, Cd, Pb, Mn, Hg, Mo, Ni, Se, Tl) using ICP-MS. Verification of the analysis method included calculation of linearity, accuracy, precision and detection limits. In addition, a comparative test with the conventional graphite furnace atomic absorption spectroscopy (GF-AAS) method was performed. In the case of Pb, Cd, and Hg in whole blood, cross-analysis between Pb, Cd, and Hg analysis methods was performed to confirm the difference between the existing method and the new method (ICP-MS). Results: The coefficient of determination (R2) was 0.999 or higher in seven items and 0.995 or higher in three items. The Pb result showed that Pearson's correlation coefficient was very high at 0.983, and the intraclass correlation coefficient was 0.966. The Cd result showed that Pearson's correlation coefficient was 0.917 between the existing method and the new analysis concentration value. Its intraclass correlation coefficient was 0.960, and there was no significant difference between the two groups. Hg had a low correlation at 0.687, and the intraclass correlation coefficient was 0.761, which was lower than that of Pb and Cd. The intra-day and inter-day accuracy of Pd and Cd were satisfactory, but Hg did not meet the criteria for both accuracy and precision when compared with the conventional analysis method. Conclusion: This study can be meaningful in that it proposes a more efficient and feasible analysis method by verifying a blood heavy metal concentration experiment using multiple simultaneous analyses. All samples were processed and analyzed using the new ICP-MS. It was confirmed that the agreement between the two methods was very high, with the agreement between the current and new methods being 0.769 to 0.998. This study proposes an efficient simultaneous methodology capable of analyzing multiple elements with small samples. In the future, studies of various applications and the reliability of ICP-MS analysis methods are required, and research on the verification of accurate, precise, and continuous analysis methods is required.

Development of The New Instrument for Measuring of Trunk-Hip Forward Flexion (새로운 체전굴 측정 방법의 개발)

  • Lee, Gun-Bum
    • Korean Journal of Applied Biomechanics
    • /
    • v.12 no.2
    • /
    • pp.245-257
    • /
    • 2002
  • The purpose of this study was to develop a simple, valid, and reliable instrument for measuring forward flexion of trunk-hip joint. The subject included 44 females for sports major of volunteers at D. Women's University. In establishing the validity, objectivity the reliability of the new flexibility test(NF-test) for trunk-hip joint, Takei- flexometer(modified Leighton flexometer) was administered as the reference instrument, and test-retest method was utilized with the best scores. Intraclass correlation coefficient was obtained to use two way-mixed effect model and this value was average measure. The Pearson product correlation coefficient of L in this study were; the new flexibility test and Takei-flexometer as the reference tool correlated r = .962 in the first test, r = .960 in the second test. The intraclass correlation coefficient of the new flexibility test between in the initial test and in the retest were R = .994 for L, R =.993 for Y, and the intraclass correlation coefficient of the new flexibility test between L and Y were R =.985 in the initial test, and R =.986 in the retest. Based on the above findings, the following conclusions are presented. It was found the new flexibility test (NF test) was a valid, reliable, objective tool for measuring forward flexion of trunk-hip joint, and possible to be recommended as he test for measuring trunk-hip flexibility in the field.

Reliability of the Functional Gait Assessment in Patients With Stroke (뇌졸중 환자에 대한 기능적 보행평가의 신뢰도)

  • Won, Jong-Im;Yu, Kyung-Hoon
    • Physical Therapy Korea
    • /
    • v.18 no.1
    • /
    • pp.64-73
    • /
    • 2011
  • After stroke, many people have problems with balance during movement. Balance is essential for the optimal functioning of the locomotor system and the performance of many activities of daily living. The Functional Gait Assessment (FGA) is a clinical tool for evaluating balance ability during walking. The test consists of ten tasks, seven tasks of the Dynamic Gait Index and three additional tasks. The purpose of this study was to evaluate the reliability and internal consistency of data obtained with the Korean version of the FGA when used with people after suffering a stroke. One-hundred participants, at least three months poststroke and able to walk at least six meters with or without a walking aid, participated in the study (age range=30~83 years; $mean{\pm}SD=58.8{\pm}10.9$). Two physical therapists and two physical therapy students rated the FGA. Intrarater and interrater reliability of the FGA were assessed using kappa statistic and intraclass correlation coefficients (2,1). The internal consistency of the FGA was assessed using the Cronbach alpha. The Cronbach alpha was good (${\alpha}$=.86~.93). The intrarater (intraclass correlation coefficient=.92~.95) and interrater reliability (intraclass correlation coefficient=.91, .95) of the total scores administered by the therapists and students were good, whereas the reliability for single item scores when administered by the physical therapists was moderate to good (kapa value=.42~.97). This study found that intrarater and interrater reliability for total FGA scores and internal consistency were good. Therefore, the Korean version of the FGA can be used as a reliable tool to assess the functional gait performance of patients after stroke.

Intertester and Intratester Reliability of Tape Measurement on Lower Extremities (줄자를 이용한 하지부피 측정시 부위별 검사자간, 검사자내 신뢰도 측정)

  • Kim, Seng-Jung;Yang, Hoi-Song;Yi, Chung-Hwi
    • Physical Therapy Korea
    • /
    • v.7 no.1
    • /
    • pp.38-45
    • /
    • 2000
  • Tape measurement for evaluating edema is frequently used by clinicians. The primary purpose of this study is to determine the intertester and intratester reliability of tape measurement carried out by two physical therapists on lower extremities. The intertester and intratester reliability of six anatomical landmarks measurements were determined in six healthy subjects. The measurements were taken in five sessions by each tester. The intraclass correlation coefficients (2,1) were between .87 and .99 for intertester reliability. Intratester reliability was .93 and .99 for A tester and .82 and .99 for B tester. The average range of variation was .13 to .54 in six landmarks. The reliability of six volume measurements was very high. These results support the use tape measurement as a reliable tool for measuring limb girth.

  • PDF

A Study of Effect on the Smoking Status using Multilevel Logistic Model (다수준 로지스틱 모형을 이용한 흡연 여부에 미치는 영향 분석)

  • Lee, Ji Hye;Heo, Tae-Young
    • The Korean Journal of Applied Statistics
    • /
    • v.27 no.1
    • /
    • pp.89-102
    • /
    • 2014
  • In this study, we analyze the effect on the smoking status in the Seoul Metropolitan area using a multilevel logistic model with Community Health Survey data from the Korea Centers for Disease Control and Prevention. Intraclass correlation coefficient (ICC), profiling analysis and two types of predicted value were used to determine the appropriate multilevel analysis level. Sensitivity, specificity, percentage of correctly classified observations (PCC) and ROC curve evaluated model performance. We showed the applicability for multilevel analysis allowed for the possibility that different factors contribute to within group and between group variability using survey data.

Bayesian Model Selection in the Unbalanced Random Effect Model

  • Kim, Dal-Ho;Kang, Sang-Gil;Lee, Woo-Dong
    • Journal of the Korean Data and Information Science Society
    • /
    • v.15 no.4
    • /
    • pp.743-752
    • /
    • 2004
  • In this paper, we develop the Bayesian model selection procedure using the reference prior for comparing two nested model such as the independent and intraclass models using the distance or divergence between the two as the basis of comparison. A suitable criterion for this is the power divergence measure as introduced by Cressie and Read(1984). Such a measure includes the Kullback -Liebler divergence measures and the Hellinger divergence measure as special cases. For this problem, the power divergence measure turns out to be a function solely of $\rho$, the intraclass correlation coefficient. Also, this function is convex, and the minimum is attained at $\rho=0$. We use reference prior for $\rho$. Due to the duality between hypothesis tests and set estimation, the hypothesis testing problem can also be solved by solving a corresponding set estimation problem. The present paper develops Bayesian method based on the Kullback-Liebler and Hellinger divergence measures, rejecting $H_0:\rho=0$ when the specified divergence measure exceeds some number d. This number d is so chosen that the resulting credible interval for the divergence measure has specified coverage probability $1-{\alpha}$. The length of such an interval is compared with the equal two-tailed credible interval and the HPD credible interval for $\rho$ with the same coverage probability which can also be inverted into acceptance regions of $H_0:\rho=0$. Example is considered where the HPD interval based on the one-at- a-time reference prior turns out to be the shortest credible interval having the same coverage probability.

  • PDF

A Study on the Reliability and Validity of Measuring the Range of Motion of the Elbow Joint Using a Smartphone Application

  • Lee, Jun Cheol
    • International Journal of Internet, Broadcasting and Communication
    • /
    • v.10 no.3
    • /
    • pp.65-72
    • /
    • 2018
  • The purpose of this study was to assess the intra-tester and inter-tester reliability and validity of elbow flexion range of motion using a smart phone used by the general public. Thirty-one general people participated in this study. The range of motion in active elbow flexion was measured with a goniometer and smart phone over two times by two observers. The intra-taster and inter-tester reliability were evaluated using the intraclass correlation coefficient(ICC). The validity was measured by Pearson's correlation coefficient. The intra-observer reliability was good in all measured items ICC>0.900. The inter-observer reliability was high with ICC>0.806. All correlation coefficients of android app and goniometer were greater than 0.868 and showed a significant positive correlation (p<0.01). The range of motion measurement with a smart phone showed acceptable reliability. Therefore, using a smartphone to measure the range of motion of the elbow joint could provide convenience and economic benefits.

Korean Translation, Cross Cultural Adaptation of Whiplash Disability Questionnaire: Pilot Study (Whiplash Disability Questionnaire의 한국어 번역 및 문화적 개작: 예비 연구)

  • Lee, Geon-Yeong;Jo, Hee-Geun;Kim, Shin-Ae;Park, Hye-Rin;Kim, Eun-Mi;Im, Hyeok-Bin;Jeong, Jun-Su
    • Journal of Korean Medicine Rehabilitation
    • /
    • v.28 no.3
    • /
    • pp.87-96
    • /
    • 2018
  • Objectives The purpose of this study is to provide more whiplash injury-specific measurement tools for Korean patients by measuring the validity and reliability of Korean version of Whiplash Disability Questionnaire (WDQ). Methods Bilingual clinicians translated the original WDQ into Korean. After consensus conference between researchers, it was back-translated into English. The pre-final version was completed and administered to 71 hospitalized patients diagnosed with whiplash injury. Validity was evaluated by concurrent validity. Reliability was assessed using Cronbach's ${\alpha}$ and intraclass correlation coefficient. Results The Korean WDQ showed good reliability with high internal consistency and intra-class correlation coefficient (Cronbach's ${\alpha}=0.96$, intraclass correlation coefficient [ICC]=0.82). Concurrent validity demonstrated positive correlations between Neck Disability Index, 36-Item Short Form Health Survey and WDQ. Conclusions The Korean version of WDQ is a valid and reliable tool for use as a measurement of whiplash injury in Korean patients, and it will be a very useful evaluation tool for both clinicians and researchers.

A Study of Test-Retest Reliability and Interrater Reliability of the Sensory Processing Scale for Children (SPS-C) (아동감각처리척도(Sensory Processing Scale for Children; SPS-C)의 검사-재검사 신뢰도와 검사자간 신뢰도 연구)

  • Kim, Kyeong-Mi;Kim, Ga-Yeon;Lee, Seung-Jin
    • The Journal of Korean Academy of Sensory Integration
    • /
    • v.20 no.2
    • /
    • pp.11-21
    • /
    • 2022
  • Objective : This study examined the test-retest reliability and interrater reliability of the Sensory Processing Scale for Children (SPS-C). Method : Senventy primary caregivers of children with sensory processing difficulties and 3 years old participated in the study. The subjects were recruited through child development centers, welfare centers, and acquaintances located in Seoul, Gyeonggi-do, Busan, and Gyeongsang-do. The test-retest reliability verification targeted 20 main caregivers of children with difficulty in sensory processing. Re-evaluation was performed within 7 to 14 days after the initial evaluation, and Pearson's correlation coefficient was used to confirm the relevance between the two time points, and the Intraclass correlation coefficient was used to confirm the degree of agreement. The interrater reliability verification was conducted with 18 primary caregivers and 18 subsidiary caregivers of children with sensory processing difficulties. Each caregiver evaluated the same child, and the Intraclass correlation coefficient was used to confirm the agreement between the two sets of caregivers. Results : The test-retest reliability was Pearson's correlation coefficient r=.914 and intraclass correlation coefficient ICC=.939, indicating a high level of relevance and agreement. The interrater reliability was an Intraclass correlation coefficient ICC=.727, which showed a moderate level of agreement, but the tactile area (ICC=.455) and proprioceptive area (ICC=.439) were not statistically significant and showed a low degree of agreement. Conclusion : Through this study, it was confirmed that the children's Sensory Processing Scale for Children (SPS-C) is a stable evaluation tool with test-retest reliability and interrater reliability verified, and it will be able to provide help in standardization studies for future clinical use.