conf_int_search         Randomisation test confidence interval limit
                        search
est_null_model          Estimates null model
gen_rand_order          Function to generate a stepped-wedge cRCT
                        randomisation allocation
lme_permute2            Generate a new permutation
outname_fit             Extracts the dependent variable name from glm,
                        lm, or mer model
perm_dist               Extracts the test statistics
permute                 Wrapper function to replicate permutations
qscore_stat             Calculates the randomisation test statistic
stepdown                Conduct the randomisation-based stepdown
                        procedure
twoarm_sim              Simulates data from a two-arm parallel cluster
                        randomised trial
