Tools and Tutorials

A tutorial on mediation analysis with SAS, SPSS, and Stata Macros
Valeri, L. and VanderWeele, T.J. (2013). Mediation analysis allowing for exposure-mediator interactions and causal interpretation: theoretical assumptions and implementation with SAS and SPSS macros. Psychological Methods, 18:137-150.

A tutorial on interaction analysis with SAS and Stata code
VanderWeele, T.J. and Knol, M.J. (2014). A tutorial on interaction. Epidemiologic Methods, in press

An Excel spreadsheet to carry out power and sample size calculations for additive and multiplicative interactions (see Appendix 2 for instructions)
VanderWeele, T.J. (2012). Sample size and power calculations for additive interactions. Epidemiologic Methods, 1:159-188.