Assessment of Repeatability and Reproducibility of Non-Invasive TBUT Measurement Using the Bland-Altman Plot

Abstract Background Application of advanced body composition measurement methods is not practical in developing countries context due to cost and unavailability of facilities. This study generated ethnic specific body fat percent prediction equation for Ethiopian adults using appropriate data. Methods A cross-sectional study was carried ifrom February to April 2015 among 704 randomly selected adult employees of Jimma University. Ethnic specific Ethiopian body fat percent (BF%) prediction equation was developed using a multivariable linear regression model with measured BF% as dependent variable and age, sex, and body mass index as predictor variables. Agreement between fat percent measured using air displacement plethysmography and body fat percent estimated using Caucasian prediction equations was determined using Bland Altman plot. Results Comparison of ADP measured and predicted BF% showed that Caucasian prediction equation underestimated body fat percent among Ethiopian adults by 6.78% (P < 0.0001). This finding is consistent across all age groups and ethnicities in both sexes. Bland Altman plot did not show agreement between ADP and Caucasian prediction equation (mean difference = 6.7825) and some of the points are outside 95% confidence interval. The caucasian prediction equation significantly underestimates body fat percent in Ethiopian adults, which is consistent across all ethnic groups in the sample. The study developed Ethnic specific BF% prediction equations for Ethiopian adults. Conclusion The Caucasian prediction equation significantly underestimates body fat percent among Ethiopian adults regardless of ethnicity. Ethiopian ethnic-specific prediction equation can be used as a very simple, cheap, and cost-effective alternative for estimating body fat percent among Ethiopian adults for health care provision in the prevention of obesity and related morbidities and for research purposes.

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Assessing Overall Diet Quality: Development and Evaluation of the Performance of a Short Self-Administrated Questionnaire SCASA

Nutrients ◽

10.3390/nu13020677 ◽

2021 ◽

Vol 13 (2) ◽

pp. 677

Author(s):

Maaike Kruseman ◽

Angeline Chatelan ◽

Eddy Farina ◽

Isabelle Carrard ◽

Jeremy Cela ◽

...

Keyword(s):

Diet Quality ◽

Quantitative Assessment ◽

Construct Validation ◽

Adult Population ◽

The Self ◽

Food Record ◽

Online Questionnaire ◽

Altman Plot ◽

Bland Altman Plot ◽

French Speaking

Several tools assessing diet quality have been developed over the last decades, but their use in public health and clinical practice is limited because they necessitate detailed quantitative assessment of food intake. Our goal was to develop and validate a score (Score d’Alimentation Saine, SCASA) based on a short self-administrated online questionnaire to assess overall diet quality. SCASA targets the adult population in French-speaking Switzerland, but it was designed in a way enabling its adaptation for other regions. The choice of the items involved experts and lay volunteers. Construct validation and inter-method reliability were assessed by screening meal plans and by comparing the self-rated scores with food-record derived scores (kappa and Bland–Altman). SCASA (17 components) discriminated adequately balanced from imbalanced meal plans (93–95% and 44–46% of maximal score). Agreement between self-assessed and food record-based scores ranged between >90% (3 items), 80–89% (3 items), 70–79% (4 items), and <70% (5 items). The Bland–Altman plot showed a mean difference of −1.60 (95% CI −2.36 to −0.84), indicating a slight overestimation of the self-assessed diet quality compared to the food record. SCASA offers a reliable way to assess overall diet quality without requiring burdensome data collection or nutrient calculations.

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Evaluation of Regional Variability and Measurement Reproducibility of Intravoxel Incoherent Motion Diffusion Weighted Imaging Using a Cardiac Stationary Phase Based ECG Trigger Method

BioMed Research International ◽

10.1155/2018/4604218 ◽

2018 ◽

Vol 2018 ◽

pp. 1-11 ◽

Cited By ~ 3

Author(s):

Zhiming Xiang ◽

Zhu Ai ◽

Jianke Liang ◽

Guijin Li ◽

Xiaolei Zhu ◽

...

Keyword(s):

Diffusion Coefficient ◽

Stationary Phase ◽

Diffusion Weighted Imaging ◽

Intravoxel Incoherent Motion ◽

Regional Variability ◽

Altman Plot ◽

Bland Altman Plot ◽

Hepatic Lobe ◽

Diffusion Weighted ◽

Pure Diffusion

Purpose. To evaluate the performance of an optimized ECG trigger diffusion weighted imaging (DWI) sequence in liver and its application in liver disease. Materials and Methods. Eighteen healthy volunteers underwent intravoxel incoherent motion diffusion weighted imaging (IVIM-DWI) scan of the liver twice in 1.5T MR scanner with signed informed consent approved by local ethic committees. A new method, called cardiac stationary phase based ECG trigger (CaspECG), and FB method were applied. The apparent diffusion coefficient (ADC) and the IVIM parameters, including pure diffusion coefficient (D), perfusion-related diffusion coefficient (D⁎), and perfusion fraction, (PF) were calculated, and then 18 region of interests were drawn on these parameter maps independently by two readers through whole hepatic lobe. The regional variability and reproducibility between two repeated scans were evaluated using interclass correlation coefficients (ICCs) and Bland-Altman plot, respectively, and compared between the CaspECG and FB methods. The signal-to-noise ratio (SNR) of DWI data was also evaluated. Result. Compared to the FB method, the proposed CaspECG method showed significant higher SNRs in DWI data, lower regional variability between left and right hepatic lobes, and higher reproducibility of ADC, PF, D, and D⁎ between repeat scans [left lobe, limit of agreement (LOA) of Bland-Altman plot: 10.1%, 18.3%, 19.8%, and 59.2%; right lobe, LOA: 10.25%, 14.15%, 16.45%, and 39.45%]. D⁎ showed the worst reproducibility in all parameters. Conclusion. The novel CaspECG method outperformed the FB method in compensating the cardiac motion induced artifacts in DWI data and generating more reliable quantitative parameters, with less regional variability and higher repeatability, especially in the left hepatic lobe.

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Heart rate assessment using NeoTapAdvancedSupport: a simulation study

Archives of Disease in Childhood - Fetal and Neonatal Edition ◽

10.1136/archdischild-2018-315408 ◽

2018 ◽

pp. fetalneonatal-2018-315408 ◽

Cited By ~ 3

Author(s):

Marco Binotti ◽

Francesco Cavallin ◽

Pier Luigi Ingrassia ◽

Nicolas J Pejovic ◽

Alice Monzani ◽

...

Keyword(s):

Heart Rate ◽

Simulation Study ◽

Mobile Application ◽

Good Accuracy ◽

Term Infant ◽

High Fidelity ◽

Altman Plot ◽

External Observer ◽

Bland Altman Plot ◽

Limited Availability

BackgroundNeoTapAdvancedSupport (NeoTapAS) is a mobile application, based on a screen tapping method that calculates the heart rate (HR). We aimed to evaluate the accuracy of NeoTapAS in reliably determining HR from auscultation in a high-fidelity simulated newborn resuscitation scenario.MethodsPaediatric residents assessed HR by auscultation plus NeoTapAS in an asphyxiated term infant scenario and orally communicated the estimated HR. An external observer simultaneously documented the actual HR set in the manikin and the communicated HR.ResultsOne hundred and sixty HR measurements were recorded. The agreement between communicated and set HR was good (Cohen’s kappa 0.80, 95% CI 0.72 to 0.87; Bangdiwala’s weighted agreement strength statistic 0.93). Bland-Altman plot showed a mean difference between communicated and set HR values of 1 beats per minute (bpm) (95% agreement limits −9 to 11 bpm).ConclusionNeoTapAS showed a good accuracy in estimating HR and it could be an important resource in settings with limited availability of ECG monitor.

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Do the Readings of Digital and Aneroid Sphygmomanometer Concur? A Clinic-Based Study in an Urban Area of South Kolkata

JOURNAL FOR CLINICAL AND DIAGNOSTIC RESEARCH ◽

10.7860/jcdr/2021/48122.15178 ◽

2021 ◽

Author(s):

Aparajita Dasgupta ◽

Foulisa Pyrbot ◽

Bobby Paul ◽

Soumit Roy ◽

Pritam Ghosh ◽

...

Keyword(s):

Blood Pressure ◽

Blood Pressure Measurement ◽

Intraclass Correlation ◽

Research Work ◽

P Value ◽

Altman Plot ◽

Cohen’S Kappa ◽

Predictive Values ◽

Bland Altman Plot ◽

Cohen's Kappa

Introduction: Hypertension is a major risk factor for cardiovascular and cerebrovascular diseases. Thus, regular and accurate measurement of Blood Pressure (BP) is essential for its early diagnosis and follow-up. There is a surge in popularity of digital sphygmomanometer due to its convenience of use and functionality. In contrast, the traditional universally accepted sphygmomanometer is aneroid type, hence there arise a need for comparison of digital and universally accepted Aneroid Sphygmomanometer in terms of agreement and correlation. Aim: To evaluate the agreement and correlation between blood pressure measurement by digital and aneroid sphygmomanometer. Materials and Methods: The clinic based cross-sectional study was conducted in the Out Patient Department (OPD) of Urban Heath Centre, All India Institute of Hygiene and Public Health, Kolkata, West Bengal, India. Adults visiting the OPD on two chosen days of the week, between June 2019 to July 2019 were selected using systematic random sampling. A total of 400 participants were included. Agreement and correlation between BP measurements by digital and aneroid sphygmomanometer was analysed by Cohen’s Kappa, Bland Altman Plot along with sensitivity, specificity and predictive values using Microsoft Excel and Statistical Package for the Social Sciences (SPSS) version 16.0. the p-value <0.05 was considered significant for the statistical test in the analysis. Results: Cohen’s Kappa value (0.59) revealed these two tools had moderate agreement in diagnosing hypertension. Sensitivity and specificity of digital sphygmomanometer taking aneroid sphygmomanometer as gold standard is 86% and 83.1% respectively. The BP readings of these two-tools showed moderate correlation as Intraclass Correlation Coefficient (ICC) for Systolic BP (SBP) and Diastolic BP (DBP) were 0.804 and 0.624, respectively. Bland Altman plot showed gross disagreement of SBP findings and disagreement between DBP findings was also noted. Conclusion: Digital device was found to be less accurate in detecting hypertension. Therefore, more similar research work is solicited to verify the accuracy of the very easy to use, the Digital BP monitor.

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Comparisons of Five Equations Used for Estimating the Glomerular Filtrations Rate in Chinese Adults

10.21203/rs.3.rs-17896/v1 ◽

2020 ◽

Author(s):

shuai fu ◽

Min Yang ◽

Si Xu ◽

Sha Wu ◽

Xiao Xiao ◽

...

Keyword(s):

Intraclass Correlation ◽

Roc Curves ◽

Severely Injured ◽

Chinese Adults ◽

Altman Plot ◽

Bland Altman Plot ◽

Chinese Adult ◽

Blood Biochemical ◽

Hospitalised Patients ◽

Kappa Value

Abstract Background We aimed to assess the performance of revised MDRD, CKD-EPI, BIS, FAS and XiangYa equation in Chinese adults Methods We collected blood biochemical data of 623 chinese adult hospitalised patients within 48 hours before they underwent 99m Tc-DTPA GFR measurement. We computed the bias (mGFR-eGFR), the precision (IQR) ,the accuray (P30）and root mean square error (RMSE) relative to mGFR of each equation to evaluate performance. The ROC curves, Kappa value of McNemar test, Bland-Altman plot and the Intraclass correlation coefficient (ICC) were used to evaluate diagnostic accuracy and concordance. Results Totally, the FAS combined Scr and cysC equation performed supreme accuracy(P30=57.5%, RMSE=19.26), the cysC-based equation performed superior to Scr-based equation. Detailed P30 of the CKD-EPI cysC , FAS cysC , MDRD, CKD-EPI Scr-cysC , CKD-EPI Scr , FAS Scr , XiangYa was 56.7%, 56.0%, 53.5%, 52.2%, 48.8%, 51.4%, 43.0%. The CKD-EPI cysC equation showed the lowest bias and the highest accuracy(bias=-2.23, P30=57.4%) in GFR<60ml/min/1.73m 2 , followed by the FASscr-cysC equation(bias=-6.89, P30=55.4%). The XiangYa equation perfomed best in GFR≥60ml/min/1.73m 2 while worst in GFR<60 ml/min/1.73m 2 with bias(-5.79 vs -19.05), IQR(18.21 vs 10.85), P30(86.2% vs 21.1%), RMSE(16.68 vs 21.34). The CKD-EPI cysC equation had the lowest bias and the best accuracy(bias=-2.23, P30=59.4%) in age ≥70 years adults, followed by the FAS Scr-cysC equation equivalented to BIS-2 Scr-cysC equation(bias -5.33 vs -4.90, P30=57.3%), while the XiangYa equation performed worstly (bias=-20.39, P30=26.6%). Best ROC AUC was gaven by the FAS Scr-cysC equation(0.951),so was it had the highest Kappa value(0.364). The lowest Bias showed in Bland-Altman plot was the CKD-EPI cysC equation(bias=7.46). The highest ICC value was gaven by the FAS Scr-cysC equation(0.921). Secondly, it was the XiangYa equation with the ICC of 0.912. Conclusions The FAS Scr-cysC equation is verified most suitable and simpler applied to Chinese population. The CKD-EPI cysC equation is appropriate used in moderately and severely injured GFR(CKD3-5stage) and Seniors over 70 years old. The XiangYa equation performed perfectly in slightly injured GFR (CKD1-2stage), while further verification of XiangYa equation in multiple region need to carried out especially in moderately and severely injured GFR and older adults.

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Bland-Altman-Plot

Lexikon der Medizinischen Laboratoriumsdiagnostik ◽

10.1007/978-3-662-49054-9_580-1 ◽

2018 ◽

pp. 1-2

Author(s):

R.-D. Hilgers ◽

N. Heussen ◽

S. Stanzel

Keyword(s):

Altman Plot ◽

Bland Altman Plot

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P1474Simpsons Triplane versus Biplane for left ventricle ejection fraction after myocardial infarction

European Heart Journal ◽

10.1093/eurheartj/ehz748.0239 ◽

2019 ◽

Vol 40 (Supplement_1) ◽

Author(s):

D Bras ◽

C Reis ◽

M J Andrade ◽

R Ribeiras ◽

M Mendes

Keyword(s):

Myocardial Infarction ◽

Ejection Fraction ◽

Past History ◽

Three Dimensional ◽

Correlation Coefficients ◽

Reference Method ◽

Patient Characteristics ◽

Anterior Wall ◽

Altman Plot ◽

Bland Altman Plot

Abstract Introduction Simpson's biplane (SBP) ignores the apical long-axis plane. It is estimated that 40% of myocardial infarction (MI)-related segmental abnormalities are located in this plane. The real-time triplane (RT3P) overcomes this issue, allowing to obtain all apical views simultaneously, at the same cardiac cycle. This method could be a more precise and reliable alternative to SBP in ejection fraction (EF) quantification in this setting. Purpose The authors aimed to compare EF assessed by two quantification methods, SBP and RT3P, using quantitative three-dimensional echocardiography (3DE) as the reference method, in patients with MI. Methods We have prospectively gathered data from 52 adult patients, which had recent or past history of MI. Exclusion criteria were the presence of atrial fibrillation, unknown coronary anatomy, significant valvular disease, left branch block, ventricular pacing and poor definition of endocardial borders. Estimation of EF by SBP, RT3P and 3DE was performed in all patients and gathered by two experienced operators. The two operators were blinded for the coronary angiography results before volume quantification. They were also blinded for their own measurements, as well as for the other operator's measurements. Spearman's correlation and linear regression were performed for correlation analysis. Bland-Altman plot was used for agreement assessment among the different methods. Interobserver agreement was assessed by Cohen's kappa. Results Patient characteristics are shown in table 1. EF calculation was feasible in all patients. There were excellent correlations between EF measured by SBP vs 3DE and RT3P vs 3DE (r=0.813 and r=0.9 respectively). Test of equality between two correlation coefficients confirmed that EF by RT3P method is significantly more correlated with the reference method, compared with EF by SBP (p=0.004). We have also performed a further analysis to study this results in special subsets. In anterior MI subset, EF by RT3P correlated by 0.909 with 3DE, versus 0.826 from EF by SBP (p=0.019). In inferior MI subset, EF by RT3P correlated by 0.779 with the reference method, versus 0.706 from EF by SBP (p=0.246). Fig 1 Correlation and Bland-Altman plot Conclusions Estimation of EF using SBP and RT3P methods by experienced operators strongly correlate with EF determined by 3DE. The RT3P method showed the strongest correlation between the two methods, which may point to its usefulness in the evaluation of EF in patients with anterior wall motion abnormalities after myocardial infarction.

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Quantitating Dialysis using two Dialysate Samples: A Simple, Practical and Accurate Approach for Evaluating Urea Kinetics

The International Journal of Artificial Organs ◽

10.1177/039139889702000803 ◽

1997 ◽

Vol 20 (8) ◽

pp. 422-427 ◽

Cited By ~ 10

Author(s):

D.S.C. Raj ◽

S. Tobe ◽

C. Saiphoo ◽

M.A. Manuel

Keyword(s):

Kinetic Parameters ◽

Flow Rate ◽

Volume Of Distribution ◽

Mean Difference ◽

Recent Analysis ◽

Altman Plot ◽

Bland Altman Plot ◽

Dialysate Flow ◽

Dialysate Flow Rate ◽

Urea Kinetics

Urea kinetics is now widely used to determine the adequacy of dialysis. Several simplified formulae are currently in use but only a few have been accepted into clinical practice because of their simplicity and ease of calculation. A recent analysis of these formulae showed that for the same set of blood urea values the calculated Kt/V can range from 1.0 to 1.5. We have developed a new dialysate-based method (2DSM) to estimate the urea kinetic parameters using dialysate and blood samples taken at the beginning and at the end of dialysis. The total urea removed (TUR) was calculated from the geometric mean of the two dialysate samples, dialysate flow rate and the duration of dialysis. The Watson formula was used to determine the volume of distribution of urea. A comparison of the 2DSM and the direct dialysate quantification (DDQ) method showed the following results (mean ± sd, n = 52): for total urea removal (TUR) 697 ± 32 vs 722 ± 37 mmol (p = 0.6, r2 = 0.928, y = 101 + 0.83 ×, mean difference 25 ± 76 mmol, see Bland-Altman plot), dialysate urea concentration (Durea) 5.55 ± 0.25 vs 5.75 ± 0.29 mmol/l (p = 0.6, r2 = 0.928, y = 0.8 + 0.82 x, mean difference 0.2 ± 0.6 mmol, see Bland-Altman plot), dialyser clearance (K) 232 ± 4.4 vs 235 ± 5.6 ml/min (p - 0.54), Kt/V 1.42 ± 0.04 vs 1.51 ± 0.04 (p = 0.21), volume of distribution of urea (Vd) 40.14 ± 1.04 vs 38.74 ± 1.2 L, (p = 0.38), and PCR 64.6 ± 2.6 vs 68.1 ± 3.1 g/day. We have developed a simple method of determining dialysate-based urea kinetics which requires two dialysate samples, one at the beginning and one at the end of dialysis and a blood sample at the midpoint of dialysis. TUR can be calculated using the dialysate flow rate and the dialysis duration and once this is known all the other kinetic parameters can be calculated.

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Bland-Altman plot agreement

Journal of Trauma and Acute Care Surgery ◽

10.1097/ta.0b013e3182509103 ◽

2012 ◽

Vol 72 (5) ◽

pp. 1452

Author(s):

Tanya L. Zakrison ◽

Victoria McCredie

Keyword(s):

Altman Plot ◽

Bland Altman Plot

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