Hello,
I would like to compare two measurement methods using a deming regression.
This is a follow-up study, and in the first study my colleagues have used a deming regression in the "Analyze it" platform in Excel. But we don't have access to the software anymore, so instead I would like to conduct the analysis using JMP v. 16.
As far as I understand, deming regression is not found in JMP?
I have seen previous posts about using orthogonal fit if the variance ratio is 1. And I've also found an add-in from russ.wolfinger@sas.com.
The Deming analysis output in "Analyze it" contains the slope, intercept, and CI and p-value for the slope and intercept. Moreover the CI values are Jackknife 95%.
The output from Orthogonal fit in JMP only contains slope, intercept and confidence interval for the slope.
So, my question is how can I interpret the JMP output and determine if the two measurement methods are different without having the CI for the intercept and p-values for the slope and intercept. Do I need additional analyses, like Bland Altman in addition to the Orthogonal fit?
And are there better options in JMP for deming regression?
Thanks.
Br.
Dilek
Yes, the orthogonal regression in the Bivariate platform is Deming regression. Alpha is set to 0.05 so the lower and upper limits are 95% confidence. The slope interval does not contain 1, so you decide that the two measurements are not equal.
Select Analyze > Specialized Modeling > Matched Pairs to see a Bland Altman analysis. That could answer the questions about the intercept not equal to zero, but you will find based on the result for the slope that it is not a constant bias, but a proportional bias.
You might also be interested in the MSA platform.
Yes, the orthogonal regression in the Bivariate platform is Deming regression. Alpha is set to 0.05 so the lower and upper limits are 95% confidence. The slope interval does not contain 1, so you decide that the two measurements are not equal.
Select Analyze > Specialized Modeling > Matched Pairs to see a Bland Altman analysis. That could answer the questions about the intercept not equal to zero, but you will find based on the result for the slope that it is not a constant bias, but a proportional bias.
You might also be interested in the MSA platform.
Thank you - this is very helpful and answers my questions.