Small Sample Adjustment of Cluster Randomized Trial R package ClusterRandSSAdj version 1.0.0 A set of functions to apply 'HC3' (FIRORES) and 'HC2' (ROOT) sandwich estimators to make small-sample adjustments to standard errors of Generalized Linear Model statistics used to analyze cluster randomized trial data. The functions in the 'ClusterRandSSAdj' package make small-sample adjustments to Generalized Linear Model parameter estimates, least squares means and pair-wise comparison of least squares means, Type III tests, and estimates from linear combinations of Generalized Linear Model parameters. For more details see Ford (2017) <doi:10.1002/bimj.201600182> and Westgate (2022) <doi:10.1177/17407745211063479>. Software Depends: R (>= 4.1) Imports: dplyr, car, emmeans, lmtest, Matrix, multcomp, sandwich Suggests: MASS, knitr, rmarkdown Barry Eggleston <beggleston@rti.org> Comprehensive R Archive Network (CRAN) Barry Eggleston [aut, cre], Rouba Chahine [aut], Phil Westgate [aut], Nathan Vandergrift [fnd] GPL (>= 3) 2026-06-26 application/tgz https://CRAN.R-project.org/package=ClusterRandSSAdj doi:10.32614/CRAN.package.ClusterRandSSAdj