A data.frame with columns tt_pfs (PFS time) and ev_pfs (corresponding
event indicator with 1 for an event and 0 for censored), and optionally
tt_pfs_uncens.
Arguments
lp_aft
(numeric) linear predictor values for the accelerate failure time model (AFT).
sigma_aft
(number) standard deviation for the AFT model.
recr_duration
(number) duration of recruitment.
rate_cens
(number) rate for the exponentially distributed censoring process.
n_events
(count) number of events to reach for the study end.
add_uncensored_pfs
(flag) whether to add the uncensored PFS as well to the resulting
data.frame.