Please cite the medflex package by the following reference:

To cite medflex in publications use:

Johan Steen, Tom Loeys, Beatrijs Moerkerke, Stijn Vansteelandt (2017). medflex: An R Package for Flexible Mediation Analysis using Natural Effect Models. Journal of Statistical Software, 76(11), 1-46.<doi:10.18637/jss.v076.i11>

For the underlying methods please cite the following papers:

Lange, T., Vansteelandt, S., & Bekaert, M. (2012). A Simple Unified Approach for Estimating Natural Direct and Indirect Effects. American Journal of Epidemiology, 176(3), 190-195.

Vansteelandt, S., Bekaert, M., & Lange, T. (2012). Imputation Strategies for the Estimation of Natural Direct and Indirect Effects. Epidemiologic Methods, 1(1), Article 7.

Loeys, T., Moerkerke, B., De Smet, O., Buysse, A., Steen, J., & Vansteelandt, S. (2013). Flexible Mediation Analysis in the Presence of Nonlinear Relations: Beyond the Mediation Formula. Multivariate Behavioral Research, 48(6), 871-894.

Corresponding BibTeX entries:

  @Article{,
    title = {{medflex}: An {R} Package for Flexible Mediation Analysis
      using Natural Effect Models},
    author = {Johan Steen and Tom Loeys and Beatrijs Moerkerke and
      Stijn Vansteelandt},
    journal = {Journal of Statistical Software},
    year = {2017},
    volume = {76},
    number = {11},
    pages = {1--46},
    doi = {10.18637/jss.v076.i11},
  }
  @Article{,
    title = {A Simple Unified Approach for Estimating Natural Direct
      and Indirect Effects},
    author = {Theis Lange and Stijn Vansteelandt and Maarten Bekaert},
    journal = {American Journal of Epidemiology},
    year = {2012},
    volume = {176},
    number = {3},
    pages = {190--195},
    url = {http://aje.oxfordjournals.org/content/176/3/190.long},
  }
  @Article{,
    title = {Imputation Strategies for the Estimation of Natural Direct
      and Indirect Effects},
    author = {Stijn Vansteelandt and Maarten Bekaert and Theis Lange},
    journal = {Epidemiologic Methods},
    year = {2012},
    volume = {1},
    number = {1},
    pages = {Article 7},
    url =
      {http://www.degruyter.com/view/j/em.2012.1.issue-1/2161-962X.1014/2161-962X.1014.xml},
  }
  @Article{,
    title = {Flexible Mediation Analysis in the Presence of Nonlinear
      Relations: Beyond the Mediation Formula},
    author = {Tom Loeys and Beatrijs Moerkerke and Olivia {De Smet} and
      Ann Buysse and Johan Steen and Stijn Vansteelandt},
    journal = {Multivariate Behavioral Research},
    year = {2013},
    volume = {48},
    number = {6},
    pages = {871--894},
    url =
      {http://www.tandfonline.com/doi/abs/10.1080/00273171.2013.832132},
  }