design_cont             Design the clinical trial for continuous
                        outcome
design_ord              Design the clinical trial for ordinal outcome
design_surv             Design the clinical trial for survival outcome
op_fwer_cont            Provides operating characteristics of group
                        sequential MAMS trial for continuous outcome
                        under null hypothesis
op_fwer_ord             Provides operating characteristics of group
                        sequential MAMS trial for ordinal outcome under
                        null hypothesis
op_fwer_surv            Provides operating characteristics of group
                        sequential MAMS trial for survival outcome
                        under null hypothesis
op_power_cont           Provides operating characteristics of group
                        sequential MAMS trial for continuous outcome
op_power_ord            Provides operating characteristics of group
                        sequential MAMS trial for ordinal outcome
op_power_surv           Provides operating characteristics of group
                        sequential MAMS trial for survival outcome
