Dear users of metaSEM,

I was wondering if someone could help me out with calculating partial correlations in stage 1 of TSSEM in the metaSEM package.

Here is the description:

Let’s say we have 3 variables (A, B, C) in our path model. A is the IV, B is the mediator, and C is the DV. When I run TSSEM stage 1, it will result in pooling a matrix of pairwise correlations. So far so good, no problem here.

Now, I introduce variable D because I want to control for omitted variable bias. I know that I can run stage 2 of TSSEM by specifying a direct effect of D on A and of D on C to control for it. So far so good, no problem here neither.

Additionally, I want to check whether the partial correlation of B-C after introducing control variable D significantly differs from the pairwise correlation of B-C in stage 1 of the analysis. So far not so good, here is the problem. Is there any method/code to calculate the matrix of partial correlations in TSSEM?

Best,

Thomas

Dear Thomas,

The partial correlation of B_C after controlling D is essentially the correlation between the residuals of B and C after controlling D. You may refer to Figure 3 in Preacher (2006).

Preacher, K. J. (2006). Testing complex correlational hypotheses with structural equation models. Structural Equation Modeling: A Multidisciplinary Journal, 13(4), 520–543. https://doi.org/10.1207/s15328007sem1304_2

Best,

Mike