Description Usage Arguments Details Value Author(s) References See Also Examples

View source: R/simulationEngines.R

This function is designed to calculate the overall variance for cluster-level outcomes in a mixedeffect Poisson model. Conditional expectation calculations are implemented.

1 | ```
mixed.eff.params(pi0, btw.clust.var, Tk)
``` |

`pi0` |
the baseline cluster-level mean on the scale of the link function |

`btw.clust.var` |
the between-cluster-variance |

`Tk` |
the at-risk time for each cluster |

The `mixed.eff.params()`

function is used by the `hayes.power.poisson()`

function to
compute the effective coefficient of variation, or k, for a particular
study design.

A numeric vector with the following three named elements, in order: ["expectation"] the overall mean of cluster-level outcomes, ["variance"] the overall variance of cluster-level outcomes, ["hayes.k"] the estimated coefficient of variation.

Nicholas G. Reich

Reich NG et al. PLoS ONE. Empirical Power and Sample Size Calculations for Cluster-Randomized and Cluster-Randomized Crossover Studies. 2012. http://ow.ly/fEn39

Hayes RJ and Bennett S. Int J Epi. Simple sample size calculation for cluster-randomized trials. 1999. http://www.ncbi.nlm.nih.gov/pubmed/10342698

1 | ```
mixed.eff.params(pi0=log(1), btw.clust.var=.5, Tk=100)
``` |

clusterPower documentation built on Sept. 5, 2017, 9:06 a.m.

Embedding an R snippet on your website

Add the following code to your website.

For more information on customizing the embed code, read Embedding Snippets.