README.Rmd

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output: github_document
---

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```{r, echo = FALSE}
knitr::opts_chunk$set(
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```
# pgf

pgf is an R implementation of the parametric g formula, first developed by Robins in the mid 1980s. The purpose of this program is to simulate the follow-up of a cohort study with complex longitudinal data under different exposure regimes. pgf accomplishes this in two steps:

* Fit empirical models to the observed complex longitudinal dataset.

* Simulate follow-up from each model, but setting the exposure/censoring values to desired levels.

You can install the latest development version from github with

    ```R
    install.packages("devtools")
    devtools::install_github("ainaimi/pgf")
    ```
If you encounter a bug or other issue, please file a request on [github](https://github.com/ainaimi/pgf/issues).

## Learning pgf

A vignette for the pgf package is currently in preparation. To learn about the parametric g formula more generally, please refer to the following citations:

* [Naimi et al (2016)](https://academic.oup.com/ije/article-abstract/doi/10.1093/ije/dyw323/2760169/An-Introduction-to-G-Methods?redirectedFrom=fulltext)
* [Daniel et al (2013)](http://onlinelibrary.wiley.com/doi/10.1002/sim.5686/abstract)
* [Robins and Hernan (2009)](https://cdn1.sph.harvard.edu/wp-content/uploads/sites/343/2013/03/abc.pdf)