topic Re: Sample size calculation: Bland-Altman plot in Statistical Procedures

Sample size calculation: Bland-Altman plot

ammarhm — Tue, 28 Aug 2018 09:29:32 GMT

Hi everyone,

could anyone please tell me how to do a sample size calculation for the difference between 2 lab tests? see this link for further info on what I want to do

https://www.medcalc.org/manual/sampling_blandaltman.php

Thank you

Re: Sample size calculation: Bland-Altman plot

FreelanceReinh — Tue, 28 Aug 2018 12:16:58 GMT

Hi @ammarhm,

Luckily, the full text of the paper containing the sample size formula is only three mouse clicks away from the MedCalc web page you refer to. The formula is not given in closed form, though. But even if you don't have a SAS/OR license to solve this equation, you can still use a Base SAS implemented solver. I have had positive experiences with macro %Bisect, which is presented in this SESUG 2007 paper.

Re: Sample size calculation: Bland-Altman plot

ammarhm — Tue, 28 Aug 2018 12:23:31 GMT

Thanks @FreelanceReinhard. I appreciate your time writing a reply to my question, and I hope you (or anyone else) dont think I am being rude here, but honestly, i am not sure how to use your reply in answering my question...

Re: Sample size calculation: Bland-Altman plot

FreelanceReinh — Tue, 28 Aug 2018 12:39:35 GMT

Did you find the paper Lu et al. (2016) containing the sample size formula?
Since you are going to do a sample size calculation, I hope that you can make sense of a sample size formula. Or are you only familiar with point-and-click tools for sample size calculation?