# Questions tagged [bland-altman-plot]

The Bland-Altman plot is used to analyze the agreement of different assays or methods of analysis. Outside of medicine, analytical chemistry and biostatistics, this plot is usually known as a Tukey mean difference plot.

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### Cutoff for repeatability assessment | above this number good repeatability, below this number bad repeatability

I have 2 sets of data that I want to study to assess the repeatability of the measurement. These are measures of fat content in MRI. My feeling is that when there is a lot of fat is very easy to ...
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### Bland-Altman plot correction for proportional bias

I am comparing 2 measurement methods with the Bland-Altman plot methodology. I found a proportional bias between the 2 measurement systems, by the regression model: difference = intercept + b1*average ...
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### Bland-Altman with non-normally-distributed differences and "0" values in one of the two series of measurements

I have two series of measurements of the same variable, coming from two different methods. The variable is represented by the weekly intake of a contaminant through diet. One method is a Food ...
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### What measure of agreeement should I use for time series data?

I am trying to compare the agreement between two measurements. Each measurement tells me when a device is worn or not worn (binary) and is sampled at the same frequency (1Hz). The measurements were ...
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### Bland Altman plot interpretation

Dear all and good day, Could please someone help me clarify what does it mean for the lower limit of the BA plot to be positive. In most of the BA plots I saw, the limit ranges from -ve to -ve number ...
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### Bland-Altman plot - two methods, multiple measures by different raters on each subject

I am working with a data set that consist of ratings from two different methods. I would like to asses the agreement between the two methods. For each subject and for each method, there are several ...
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### Bland-Altman plot and normality of the differences?

An assumption of the Bland-Altman limits of agreement is that the differences are normally distributed. I have a variable I have to study by a Bland&Altman plot with a leptokurtic distribution (...
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### Descriptive statistics for 2 variables grouped by gender with spss

I have 3 variables one categorical gender and the others are the IQBefore and IQAfter which ...
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1 vote
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### Calculating interclass correlation but with different observer experience

I have tried finding an answer to the following question both here and using PubMed and google but without luck. I have been asked to calculate the intraclass correlation coefficient from the ...
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### Corrected Standard Deviation for Differences in Means

In the published work of Altman and Bland: Statistical Methods For Assessing Agreement Between Two Methods of Clinical Measurement, Lancet 1986 (https://www-users.york.ac.uk/~mb55/meas/ba.pdf) , page ...
1 vote
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### Agreement between methods with multiple observations per individual

I am having trouble interpreting agreement analysis in R. I have a dataset similar to that below with multiple paired observations per subject: ...
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### Repeated measures mixed model correlation between measurements

I am interested in looking at the correlation between two types of heart function measurements over time. test1 can be considered the true value. The true value (<...
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1 vote
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### Repeated Measures Test for Comparing Devices With Multiple Samples

I ran an experiment using the same device, under two attachment conditions. The first condition was “loose” and the second condition was “tight.” I tested the device on 8 subjects under both ...
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### Comparing fitting methods for the same model. Bland-Altman and Mann-Whitney

I have fit my experimental data (about 50 analysis) to the same model using two diferente methods. The model is of the type: $y = A + B * (x^C)$. I obtained my results as two tables with the ...
981 views

### Proper name for "modified Bland–Altman plot"

My lab uses what our PI calls "modified Bland–Altman plots" to analyze regression quality. I'd like to know what the generally used name is for these plots. A Bland–Altman plot compares the ...
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1 vote
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### Can I use Bland–Altman plots?

Bland Altman (B.A.) method asses the agreement between two measurement methods and can evaluate the mean difference (bias) of one method against the "gold standard method." With the B.A. method we ...
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Let me introduce the context: I need to evaluate how my TAs tend to grade students. Ideally I would like to pinpoint whether they show some sort of internal consistency (e.g., a TA usually grades ...
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### Is there a name for a differences versus differences plot?

I'm aware of the Bland–Altman plot where the differences between two measures of a given parameter (obtained with two different methods) are plotted against their averages. What I need to plot, are ...
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### Comparing two sets of limits of agreement (continuous outcome) - R

I am planning an analysis where I will have children and parents rating the child's pain (numerical score). For each child, I will have a child pain score and a parent pain score. The dyads will ...
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### Can I use ICC and bland altman plot to study agreement of small data?

I have data set with small sample size, like 10 pairs of continuous data. I checked out kappa and percentage agreement, both seems not appropriate for agreement analysis. Can I stick to use ICC and ...
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1 vote
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### Performing Bland Altman Plot with values that ranges from positive and negaitve values

I just started learning about Bland-Altman plots. So my data consists of angles from a particular device and another set of angles from another device. The angles on both devices vary between -5 ...
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### Bland & Altman plot for repeated measures using one measuring device

I am examining the reliability of a measuring device by measuring a force generated på test persons 7 days apart using R. In order to assess this properly I want to make a Bland & Altman plot ...
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### Bland-Altman (Tukey Mean-Difference) plot for differing scales

I find that Bland-Altman plots for comparing two methods are extremely useful in assessing agreement. However, I'm curious if there is a similar method or transformation that can be used when the ...
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### Comparing measurements obtained from >2 devices (Bland-Altman, Tukey mean difference plot)

I would like to compare different measurements in regard to agreement. Quite often this is done using a Bland-Altman plot (also called Tukey mean difference plot) in medical literature. What I would ...
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### What are the tests to measure agreement between two methods of measurement when the unit of measurement is different between the two methods?

Bland-Altman plot measure the agreement between two different methods which measures the same variable. As far as I understand Bland-Altman can measure only if the two methods have the same unit of ...
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### Creating and interpreting Bland-Altman plot

Yesterday I heard of the Bland-Altman plot for the first time. I have to compare two methods of measuring blood pressure, and I need to produce a Bland-Altman plot. I am not sure if I get everything ...
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### What is an "Unpaired Bland-Altman plot"?

I found this quote: Unpaired Bland-Altman plots were used to check systematic or bias errors in the SPECT myocardial uptake coefficients with respect to the reference standard PET data. in ...
1 vote
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### How should I compare two methods for obtaining the frequency of several events?

I am using two different methods to obtain the frequency of several events. Can I use a scatter plot to graph the frequency of an event obtained by Method A against the one obtained by Method B? And ...
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### How to "prove" that new measurement tool & process gives same result as old?

I am new to the area of statistics and I am hoping you can suggest methods I may use. Sorry if this is long but I might as well be as clear as possible on my first post :) What I am worried most is ...
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