Apply a group-sequential design to one simulated trial — apply_GSD_to

Runs the looks of a group-sequential design on one simulated trial, in order, stopping at the first look whose rule is met: efficacy if Z exceeds the efficacy critical value, futility under the design's futility rule ("Beta": Z below the beta-spending bound; "MatchedZ": Z below GSD_model$futility_boundary_Z; "PP": predictive probability below GSD_model$kappa), and otherwise the final analysis. Each look cuts the trial with cens_data at floor(IF * total_events) events. This is the engine of calc_dte_assurance_adaptive. For simulation studies, use run_paired_scenario and apply_design_rule, which evaluate all designs on the same replicates.

Usage

apply_GSD_to_trial(
  n_c,
  n_t,
  trial_data,
  design,
  total_events,
  GSD_model,
  control_model = NULL,
  effect_model = NULL,
  recruitment_model = NULL,
  analysis_model = NULL,
  update_priors_sims = NULL,
  PP_sims = NULL,
  .PP_val = NULL
)

Arguments

n_c, n_t: Planned number of patients in the control / treatment arm.
trial_data: A simulated trial with columns time, group, rec_time and pseudo_time.
design: The rpact design, from make_gsd_design.
total_events: Maximum planned number of events.
GSD_model: The design specification (see calc_dte_assurance_adaptive).
control_model, effect_model, recruitment_model: Analysis prior and recruitment model, used only for "PP" futility (recruitment must be method = "power" with power = 1).
analysis_model: Test specification (method, alpha, alternative_hypothesis, and rho, gamma, t_star, s_star as needed); defaults to a one-sided LRT at 0.025.
update_priors_sims, PP_sims: MCMC samples per chain and predictive draws; required for "PP" futility.
.PP_val: Internal, for testing: a precomputed predictive probability to use at the PP futility look instead of computing it.

Value

A list with decision ("Stop for efficacy", "Stop for futility", "Successful at final" or "Unsuccessful at final"), stop_time, sample_size, PP_val, converged and Z_probs.