HTMT is actually disattenuated correlation and uses standardized alpha (i.e., parallel reliability) as the reliability coefficient. Although advertised as a new technique, it is actually a very old technique. A better way to find the error-corrected correlation is to use CFA. Please refer to the following article. Online Supplement 4 contains the Mplus code.

Paper

https://www.researchgate.net/publication/344411763_An_Updated_Guideline_for_Assessing_Discriminant_Validity

Tutorial

https://www.researchgate.net/publication/344411927_Online_supplement_4_-_Tutorial_on_calculationspdf

Thanks a lot, Eunseong Cho !!

I will certainly look into this!

Best

John-Kåre

It is a novel approach for assessing discriminant validity was introduced by Henseler, Ringle and Sarstedt (2015): the heterotrait-monotrait ratio of correlations (HTMT). The HTMT is a measure of similarity between latent variables. If the HTMT is clearly smaller than one, discriminant validity can be regarded as established. In many practical situations, a threshold of 0.85 reliably distinguishes between those pairs of latent variables that are discriminant valid and those that are not. Monte Carlo simulations provide evidence for the HTMT's favorable classification performance (Franke & Sarstedt, 2019; Voorhees, Brady, Calantone & Ramirez, 2016) You can use ADANCO free version, it very fast in calculations.