Dickinson_design        Raw county-level variables for study 1 in
                        Dickinson et al (2015)
Dickinson_outcome       Simulated individual-level binary outcome and
                        baseline variables for study 1 in Dickinson et
                        al (2015)
cptest                  Clustered permutation test for cluster
                        randomized trials
cvrall                  Covariate-constrained randomization for cluster
                        randomized trials
cvrcov                  Covariate-by-covariate constrained
                        randomization for cluster randomized trials
