scholarly journals A Comparison of Anti-Nuclear Antibody Quantification Using Automated Enzyme Immunoassays and Immunofluorescence Assays

2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Renata Baronaite ◽  
Merete Engelhart ◽  
Troels Mørk Hansen ◽  
Gorm Thamsborg ◽  
Hanne Slott Jensen ◽  
...  
Keyword(s):  
Confidence Interval ◽  
Screening Test ◽  
Cohen’S Kappa ◽  
Enzyme Immunoassays ◽  
Double Stranded Dna ◽  
Cohen's Kappa ◽  
Kappa Value ◽  
Fluorescence Assays ◽  
Good Agreement

Anti-nuclear antibodies (ANA) have traditionally been evaluated using indirect fluorescence assays (IFA) with HEp-2 cells. Quantitative immunoassays (EIA) have replaced the use of HEp-2 cells in some laboratories. Here, we evaluated ANA in 400 consecutive and unselected routinely referred patients using IFA and automated EIA techniques. The IFA results generated by two independent laboratories were compared with the EIA results from antibodies against double-stranded DNA (dsDNA), from ANA screening, and from tests of the seven included subantigens. The final IFA and EIA results for 386 unique patients were compared. The majority of the results were the same between the two methods (n=325, 84%); however, 8% (n=30) yielded equivocal results (equivocal-negative and equivocal-positive) and 8% (n=31) yielded divergent results (positive-negative). The results showed fairly good agreement, with Cohen’s kappa value of 0.30 (95% confidence interval (CI) = 0.14–0.46), which decreased to 0.23 (95% CI = 0.06–0.40) when the results for dsDNA were omitted. The EIA method was less reliable for assessing nuclear and speckled reactivity patterns, whereas the IFA method presented difficulties detecting dsDNA and Ro activity. The automated EIA method was performed in a similar way to the conventional IFA method using HEp-2 cells; thus, automated EIA may be used as a screening test.

scholarly journals Lateral throat form classification using a customized gauge and Neil’s method – a comparative study

2018 ◽  
Vol 8 (4) ◽  
pp. 54-57
Author(s):  
Sabina Poudel ◽  
Minu Dhungana ◽  
Rajani Karki ◽  
Prabhat Shrestha
Keyword(s):  
Geriatric Patients ◽  
Observer Variation ◽  
Observer Agreement ◽  
Cohen’S Kappa ◽  
Kappa Test ◽  
Cohen's Kappa ◽  
Kappa Value ◽  
Edentulous Patients ◽  
Observer Accuracy ◽  
Good Agreement

Introduction: Lateral throat form (LTF) is the critical area which has to be recorded properly for obtaining proper retention and stability in complete denture especially in geriatric patients with resorbed ridges. Popular method used for determining LTF is Neil’s method which depends on the forces applied by the floor of mouth when the tongues protrude out. Since the perception of the forces differs among different operators, there are high chances of error in the classification. So, customized instrument was fabricated to prevent this inter-observer variation. The aim of the study was to compare the inter-observer accuracy between Neil’s method of classifi­cation and classification done by customized gauze. Methods and methodology: Total 30 edentulous patients were taken. Two observers measured the LTF depth by customized tool and also by Neil’s method. Cohen’s kappa test was used to evaluate the agreement between two operators in two different classifications. Result: The agreement between the two observers was evaluated by means of Cohen’s kappa value. There was good agreement between observers in proposed classification done by customized tool with kappa value 0.658 and fair inter-observer agreement with kappa value 0.0492. Conclusion: The method of measuring the depth of LTF with fabricated instrument was more accurate and reliable than Neil’s method.

scholarly journals Development, Relative Validity and Reproducibility of the Aus-SDS (Australian Short Dietary Screener) in Adults Aged 70 Years and above

Nutrients ◽  
2020 ◽  
Vol 12 (5) ◽  
pp. 1436 ◽  
Author(s):  
Adelle M. Gadowski ◽  
Tracy A. McCaffrey ◽  
Stephane Heritier ◽  
Andrea J. Curtis ◽  
Natalie Nanayakkara ◽  
...  
Keyword(s):  
Daily Intake ◽  
Kappa Statistic ◽  
Food Groups ◽  
Cohen’S Kappa ◽  
Relative Validity ◽  
Cohen's Kappa ◽  
Spearman’S Correlation ◽  
Acceptable Agreement ◽  
Dietary Screener ◽  
Good Agreement

The aim of this study was to assess the relative validity and reproducibility of a six-item Australian Short Dietary Screener (Aus-SDS). The Aus-SDS assessed the daily intake of core food groups (vegetables, fruits, legumes and beans, cereals, protein sources and dairy sources) in 100 Australians (52 males and 48 females) aged ≥70 years. Relative validity was assessed by comparing intakes from the Aus-SDS1 with an average of three 24-h recalls (24-HRs), and reproducibility using two administrations of the Aus-SDS (Aus-SDS1 and Aus-SDS2). Cohen’s kappa statistic between the Aus-SDS1 and 24-HRs showed moderate to good agreement, ranging from 0.44 for fruits and dairy to 0.64 for protein. There was poor agreement for legume intake (0.12). Bland–Altman plots demonstrated acceptable limits of agreement between the Aus-SDS1 and 24-HRs for all food groups. Median intakes obtained from Aus-SDS1 and Aus-SDS2 did not differ. For all food groups, Cohen’s kappa statistic ranged from 0.68 to 0.89, indicating acceptable agreement between the Aus-SDS1 and Aus-SDS2. Spearman’s correlation coefficient between Aus-SDS1 and 24-HRs across all food groups ranged from 0.64 for fruit to 0.83 for protein. We found the Aus-SDS to be a useful tool in assessing daily intake of core food groups in this population.

Validity of participants’ self-reported diagnosis for a work absence due to a mental health problem compared with physician-certified diagnosis for the same work absence among 709 Canadian workers

2020 ◽  
pp. oemed-2020-106658
Author(s):  
Mahée Gilbert-Ouimet ◽  
Xavier Trudel ◽  
Karine Aubé ◽  
Ruth Ndjaboue ◽  
Caroline S Duchaine ◽  
...  
Keyword(s):  
Mental Health ◽  
Mental Health Problem ◽  
Sensitivity And Specificity ◽  
Health Problem ◽  
High Specificity ◽  
Work Absence ◽  
Cohen’S Kappa ◽  
Cohen's Kappa ◽  
Kappa Value ◽  
Total Agreement

ObjectivesThis study assesses the validity of a self-reported mental health problem (MHP) diagnosis as the reason for a work absence of 5 days or more compared with a physician-certified MHP diagnosis related to the same work absence. The potential modifying effect of absence duration on validity is also examined.MethodsA total of 709 participants (1031 sickness absence episodes) were selected and interviewed. Total per cent agreement, Cohen’s kappa, sensitivity and specificity values were calculated using the physician-certified MHP diagnosis related to a given work absence as the reference standard. Stratified analyses of total agreement, sensitivity and specificity values were also examined by duration of work absence (5–20 workdays,>20 workdays).ResultsTotal agreement value for self-reported MHP was 90%. Cohen’s kappa value was substantial (0.74). Sensitivity was 77% and specificity was 95%. Absences of more than 20 workdays had a better sensitivity than absences of shorter duration. A high specificity was observed for both short and longer absence episodes.ConclusionThis study showed high specificity and good sensitivity of self-reported MHP diagnosis compared with physician-certified MHP diagnosis for the same work absence. Absences of longer durations had a better sensitivity.

scholarly journals Evaluation of paper-based and web-based food frequency questionnaires for 7-year-old children in Singapore

2021 ◽  
pp. 1-35
Author(s):  
Jun S Lai ◽  
Jason Loh ◽  
Jia Ying Toh ◽  
Ray Sugianto ◽  
Marjorelee T Colega ◽  
...  
Keyword(s):  
Parent Report ◽  
Dietary Intakes ◽  
Food Groups ◽  
Cohen’S Kappa ◽  
Web Based ◽  
Food Frequency ◽  
Cohen's Kappa ◽  
Good Ability ◽  
The Web ◽  
Good Agreement

Abstract Advances in technology enabled the development of a web-based, pictorial food frequency questionnaire (FFQ) to collect parent-report dietary intakes of 7-year-old children in the GUSTO study. This study aimed to compare intakes estimated from a paper-FFQ and a web-FFQ, and examine the relative validity of both FFQs against 3-day diet records (3DDR). Ninety-two mothers reported food intakes of their 7-year-old child on a paper-FFQ, a web-FFQ and a 3DDR. A usability questionnaire collected participants’ feedback on the web-FFQ. Correlations and agreement in energy, nutrients and food groups intakes between the dietary assessments were evaluated using Pearson’s correlation, Lin’s concordance, Bland-Altman plots, Cohen’s kappa and tertile classification. The paper- and web-FFQ had good correlations (≥0.50) and acceptable-good agreement (Lin’s concordance ≥0.30; Cohen’s kappa ≥0.41; ≥50% correct and ≤10% mis-classification into same or extreme tertiles). Compared to 3DDR, both FFQs showed poor agreement (<0.30) in assessing absolute intakes except micronutrients (web-FFQ had acceptable-good agreement); but showed acceptable-good ability to classify children into tertiles (κ≥0.21; ≥40% and ≤15% correct or misclassification). Bland-Altman plots suggest good agreement between web-FFQ and 3DDR in assessing micronutrients and several food groups. The web-FFQ was well-received (e.g. >89% found it user-friendly), and majority (81%) preferred the web-FFQ over the paper-FFQ. The newly developed web-FFQ produced intake estimates comparable to the paper-FFQ, has acceptable-good agreement with 3DDR in assessing absolute micronutrients intakes, and acceptable-good ability to classify children according to categories of intakes. The positive acceptance of the web-FFQ makes it a feasible tool for future dietary data collection.

scholarly journals Learning the Orientation of a Loosely-Fixed Wearable IMU Relative to the Body Improves the Recognition Rate of Human Postures and Activities

Sensors ◽  
2019 ◽  
Vol 19 (13) ◽  
pp. 2845 ◽  
Author(s):  
Michael B. Del Del Rosario ◽  
Nigel H. Lovell ◽  
Stephen J. Redmond
Keyword(s):  
Confidence Interval ◽  
Recognition Rate ◽  
The Body ◽  
Training Data ◽  
Measurement Unit ◽  
Cohen’S Kappa ◽  
Younger Adults ◽  
Cohen's Kappa ◽  
Overall Performance ◽  
Using Data

Features were developed which accounted for the changing orientation of the inertial measurement unit (IMU) relative to the body, and demonstrably improved the performance of models for human activity recognition (HAR). The method is proficient at separating periods of standing and sedentary activity (i.e., sitting and/or lying) using only one IMU, even if it is arbitrarily oriented or subsequently re-oriented relative to the body; since the body is upright during walking, learning the IMU orientation during walking provides a reference orientation against which sitting and/or lying can be inferred. Thus, the two activities can be identified (irrespective of the cohort) by analyzing the magnitude of the angle of shortest rotation which would be required to bring the upright direction into coincidence with the average orientation from the most recent 2.5 s of IMU data. Models for HAR were trained using data obtained from a cohort of 37 older adults (83.9 ± 3.4 years) or 20 younger adults (21.9 ± 1.7 years). Test data were generated from the training data by virtually re-orienting the IMU so that it is representative of carrying the phone in five different orientations (relative to the thigh). The overall performance of the model for HAR was consistent whether the model was trained with the data from the younger cohort, and tested with the data from the older cohort after it had been virtually re-oriented (Cohen’s Kappa 95% confidence interval [0.782, 0.793]; total class sensitivity 95% confidence interval [84.9%, 85.6%]), or the reciprocal scenario in which the model was trained with the data from the older cohort, and tested with the data from the younger cohort after it had been virtually re-oriented (Cohen’s Kappa 95% confidence interval [0.765, 0.784]; total class sensitivity 95% confidence interval [82.3%, 83.7%]).

scholarly journals POS1401 ASSESSMENT OF INTERREADER RELIABILITY IN SCORING PATIENTS WITH HAND OSTEOARTHRITIS AND PSORIATIC ARTHRITIS BY FLUORESCENCE OPTICAL IMAGING

2021 ◽  
Vol 80 (Suppl 1) ◽  
pp. 983.2-983
Author(s):  
B. Drude ◽  
Ø. Maugesten ◽  
S. G. Werner ◽  
G. R. Burmester ◽  
J. Berger ◽  
...  
Keyword(s):  
Psoriatic Arthritis ◽  
Optical Imaging ◽  
Phase 1 ◽  
Hand Osteoarthritis ◽  
Scoring Method ◽  
Cohen’S Kappa ◽  
Fluorescence Optical Imaging ◽  
Cohen's Kappa ◽  
Kappa Value ◽  
Pip Joint

Background:Fluorescence Optical Imaging (FOI) utilises the fluorophore indocyanine green (ICG) to reflect enhanced microcirculation in hand and finger joints due to inflammation.Objectives:We wanted to assess the interreader reliability of FOI enhancement in patients with hand osteoarthritis (OA) and psoriatic arthritis (PsA). Furthermore, predefined typical morphologic patterns were included to determine the ability of FOI to discriminate between both diagnoses.Methods:An atlas with example images of grade 0-3 in different joint groups and typical morphologic patterns (‘streaky signals’[1], ‘green/blue nail sign’[2], ‘Werner sign’[3,4], and ‘Bishop’s crozier sign’) of PsA and hand OA was created. Two readers scored all joints in both hands (30 in total) of 20 cases with hand OA and PsA. The cases were randomly mixed and both readers were blinded to diagnosis. Each joint was rated on a semiquantitative scale from 0 to 3 in five different images (PrimaVista Mode (PVM), phase 1, 2 (first and middle image), and 3) during the FOI sequence according to the scoring method FOIAS (fluorescence optical imaging activity score)[1,3]. Interreader reliability on scoring joint enhancement was calculated using linear weighted Cohen’s kappa (κ). Agreement on diagnosis (hand OA vs. PsA) and different morphologic patterns was assessed by calculating (regular) Cohen’s kappa.Results:Overall agreement on scoring joint enhancement (all phases) was substantial (κ = 0.75), with greatest consensus in phase 2 first (κ = 0.75) and lowest agreement in phase 1 (κ = 0.46). Reliability varied in different joint groups (wrist, MCP, (P)IP, DIP), with almost perfect overall agreement on PIP joint affection (κ = 0.81), substantial agreement on wrist (κ = 0.69) and DIP joint affection (κ = 0.63), and moderate agreement on MCP joint affection (κ = 0.49) across all phases. Consensus on morphologic patterns showed overall fair agreement (κ = 0.37) with a similar kappa value on the ability to discriminate between both diagnoses (κ = 0.3).Conclusion:Joint enhancement in FOI can be reliably assessed using a predefined scoring method. The ability of FOI to differentiate between hand OA and PsA seems to be limited. Clearer definition and more training might be needed to better agree on morphologic patterns in FOI.References:[1] Glimm AM, Werner SG, Burmester GR, et al. Ann Rheum Dis. 2016 Mar;75(3):566-570[2] Wiemann O, Werner SG, Langer HE, et al. J Dtsch Dermatol Ges. 2019 Feb;17(2):138-148[3] Werner SG, Langer HE, Ohrndorf S, et al. Ann Rheum Dis. 2012 Apr;71(4):504-510[4] Zeidler H 2019. Fluoreszenzoptische Bildgebung. In: Zeidler H, Michel BA. Differenzialdiagnose rheumatischer Erkrankungen 5. Aufl. Springer, Heidelberg, S. 88-89Disclosure of Interests:Benedict Drude: None declared, Øystein Maugesten: None declared, Stephanie Gabriele Werner: None declared, Gerd Rüdiger Burmester: None declared, Jörn Berger Employee of: Xiralite GmbH, Ida K. Haugen: None declared, Sarah Ohrndorf: None declared

scholarly journals Seroprevalence of SARS-CoV-2 Assessed by Four Chemiluminescence Immunoassays and One Immunocromatography Test for SARS-Cov-2

2021 ◽  
Vol 9 ◽  
Author(s):  
Pellegrino Cerino ◽  
Alfonso Gallo ◽  
Biancamaria Pierri ◽  
Carlo Buonerba ◽  
Denise Di Concilio ◽  
...  
Keyword(s):  
Screening Program ◽  
Kappa Coefficient ◽  
Cohen’S Kappa ◽  
Campania Region ◽  
Entire Cohort ◽  
Cohen's Kappa ◽  
Rapid Tests ◽  
Second Wave ◽  
Cohen’S Kappa Coefficient ◽  
Good Agreement

The onset of the new SARS-CoV-2 coronavirus encouraged the development of new serologic tests that could be additional and complementary to real-time RT-PCR-based assays. In such a context, the study of performances of available tests is urgently needed, as their use has just been initiated for seroprevalence assessment. The aim of this study was to compare four chemiluminescence immunoassays and one immunochromatography test for SARS-Cov-2 antibodies for the evaluation of the degree of diffusion of SARS-CoV-2 infection in Salerno Province (Campania Region, Italy). A total of 3,185 specimens from citizens were tested for anti-SARS-CoV-2 antibodies as part of a screening program. Four automated immunoassays (Abbott and Liaison SARS-CoV-2 CLIA IgG and Roche and Siemens SARS-CoV-2 CLIA IgM/IgG/IgA assays) and one lateral flow immunoassay (LFIA Technogenetics IgG–IgM COVID-19) were used. Seroprevalence in the entire cohort was 2.41, 2.10, 1.82, and 1.85% according to the Liaison IgG, Abbott IgG, Siemens, and Roche total Ig tests, respectively. When we explored the agreement among the rapid tests and the serologic assays, we reported good agreement for Abbott, Siemens, and Roche (Cohen's Kappa coefficient 0.69, 0.67, and 0.67, respectively), whereas we found moderate agreement for Liaison (Cohen's kappa coefficient 0.58). Our study showed that Abbott and Liaison SARS-CoV-2 CLIA IgG, Roche and Siemens SARS-CoV-2 CLIA IgM/IgG/IgA assays, and LFIA Technogenetics IgG-IgM COVID-19 have good agreement in seroprevalence assessment. In addition, our findings indicate that the prevalence of IgG and total Ig antibodies against SARS-CoV-2 at the time of the study was as low as around 3%, likely explaining the amplitude of the current second wave.

scholarly journals Kappa Coefficients for Missing Data

2019 ◽  
Vol 79 (3) ◽  
pp. 558-576 ◽  
Author(s):  
Alexandra De Raadt ◽  
Matthijs J. Warrens ◽  
Roel J. Bosker ◽  
Henk A. L. Kiers
Keyword(s):  
Missing Data ◽  
Mean Squared Error ◽  
Kappa Coefficient ◽  
Complete Data ◽  
Cohen’S Kappa ◽  
Nominal Scale ◽  
Listwise Deletion ◽  
Squared Error ◽  
Cohen's Kappa ◽  
Kappa Value

Cohen’s kappa coefficient is commonly used for assessing agreement between classifications of two raters on a nominal scale. Three variants of Cohen’s kappa that can handle missing data are presented. Data are considered missing if one or both ratings of a unit are missing. We study how well the variants estimate the kappa value for complete data under two missing data mechanisms—namely, missingness completely at random and a form of missingness not at random. The kappa coefficient considered in Gwet ( Handbook of Inter-rater Reliability, 4th ed.) and the kappa coefficient based on listwise deletion of units with missing ratings were found to have virtually no bias and mean squared error if missingness is completely at random, and small bias and mean squared error if missingness is not at random. Furthermore, the kappa coefficient that treats missing ratings as a regular category appears to be rather heavily biased and has a substantial mean squared error in many of the simulations. Because it performs well and is easy to compute, we recommend to use the kappa coefficient that is based on listwise deletion of missing ratings if it can be assumed that missingness is completely at random or not at random.

scholarly journals The NIEER AVHRR snow cover extent product over China – a long-term daily snow record for regional climate research

2021 ◽  
Vol 13 (10) ◽  
pp. 4711-4726
Author(s):  
Xiaohua Hao ◽  
Guanghui Huang ◽  
Tao Che ◽  
Wenzheng Ji ◽  
Xingliang Sun ◽  
...  
Keyword(s):  
Snow Cover ◽  
Regional Climate ◽  
Commission Error ◽  
Cloud Detection ◽  
Cohen’S Kappa ◽  
Cohen's Kappa ◽  
Snow Cover Extent ◽  
Kappa Value ◽  
Academy Of Sciences

Abstract. A long-term Advanced Very High Resolution Radiometer (AVHRR) snow cover extent (SCE) product from 1981 until 2019 over China has been generated by the snow research team in the Northwest Institute of Eco-Environment and Resources (NIEER), Chinese Academy of Sciences. The NIEER AVHRR SCE product has a spatial resolution of 5 km and a daily temporal resolution, and it is a completely gap-free product, which is produced through a series of processes such as the quality control, cloud detection, snow discrimination, and gap-filling (GF). A comprehensive validation with reference to ground snow-depth measurements during snow seasons in China revealed the overall accuracy is 87.4 %, the producer's accuracy was 81.0 %, the user's accuracy was 81.3 %, and the Cohen's kappa (CK) value was 0.717. Another validation with reference to higher-resolution snow maps derived from Landsat-5 Thematic Mapper (TM) images demonstrates an overall accuracy of 87.3 %, a producer's accuracy of 86.7 %, a user's accuracy of 95.7 %, and a Cohen's kappa value of 0.695. These accuracies were significantly higher than those of currently existing AVHRR products. For example, compared with the well-known JASMES AVHRR product, the overall accuracy increased approximately 15 %, the omission error dropped from 60.8 % to 19.7 %, the commission error dropped from 31.9 % to 21.3 %, and the CK value increased by more than 114 %. The new AVHRR product is already available at https://doi.org/10.11888/Snow.tpdc.271381 (Hao et al., 2021).

scholarly journals On Agreement Tables with Constant Kappa Values

2014 ◽  
Vol 2014 ◽  
pp. 1-5 ◽  
Author(s):  
Matthijs J. Warrens
Keyword(s):  
Categorical Variables ◽  
Cohen’S Kappa ◽  
Cohen's Kappa ◽  
Special Cases ◽  
Kappa Value

Kappa coefficients are standard tools for summarizing the information in cross-classifications of two categorical variables with identical categories, here called agreement tables. When two categories are combined the kappa value usually either increases or decreases. There is a class of agreement tables for which the value of Cohen’s kappa remains constant when two categories are combined. It is shown that for this class of tables all special cases of symmetric kappa coincide and that the value of symmetric kappa is not affected by any partitioning of the categories.

Sign in / Sign up

Export Citation Format

Share Document