crit_2_of_3: Critical value at second interim analysis

In dominicmagirr/gsdelayed: Design a group-sequential trial when anticipating a delayed effect.

Critical value at second interim analysis

Description

Find the critical value at the second interim analysis of a three-stage design

Usage

crit_2_of_3(info_frac_sf, info_frac_1_2, crit_1, design,
  alpha_spend_f = ldobf, alpha_one_sided = 0.025)

Arguments

info_frac_sf	Information fraction to be used in the spending function at the second interim.
info_frac_1_2	The observed information fraction: determines covariance of test statistics.
crit_1	The critical value for the z-statistic at the first interim, found via crit_1_of_3.
alpha_spend_f	The alpha-spending function. Default is the Lan-DeMets O'Brien-Fleming function.
alpha_one_sided	One-sided alpha level.
var_u_int_1	The observed variance of the weighted log-rank statistic at the first interim.

Value

The critical value for the second interim z-statistic.

dominicmagirr/gsdelayed documentation built on May 15, 2024, 8:24 a.m.