How to calculate sample size for marginal structural model

Anjana22 — Wed, 23 Mar 2022 15:37:00 GMT

Hello,

I want to calculate sample size for the marginal structural model using SAS.

I really appreciate any help

Thanks in advance.

Regards,

Anjana

Re: How to calculate sample size for marginal structural model

SteveDenham — Thu, 24 Mar 2022 14:04:01 GMT

I consider myself as pretty good at sample size determination, but there is not enough information here to do much. To successfully calculate this, we would need:

Some idea of what the particular marginal structural model looks like (number of factors, relationship between factors)

A statement of what size difference you wish to detect in the various factors

A preliminary estimate of the variability (this can be addressed using multiple runs at various levels)

A preliminary estimate of the correlations between factors (for instance, the off-diagonal entries in a matrix)

The acceptable risk for both Type I and Type II errors

From this, a simulation approach could be used, as I doubt very much that any of the closed-form methods available in PROC POWER are good candidates for structural models. I suspect that you are going to have to go through the literature at a fairly detailed level to set up a reasonable null model and alternative model.

SteveDenham

topic Re: How to calculate sample size for marginal structural model in Statistical Procedures

How to calculate sample size for marginal structural model

Re: How to calculate sample size for marginal structural model