fac2x2design {factorial2x2}

Power for the Equal Allocation 3, Proportional Allocation 2, and Equal Allocation 2 procedures.

Description

Power for the Equal Allocation 3, Proportional Allocation 2, and Equal Allocation 2 procedures.

Usage

fac2x2design(
  n,
  rateC,
  hrA,
  hrB,
  hrAB,
  mincens,
  maxcens,
  dig = 2,
  alpha = 0.05,
  niter = 5,
  abseps = 0.001,
  corAa = 1/sqrt(2),
  corAab = 1/sqrt(2),
  coraab = 1/2
)

Arguments

n

total sample size

rateC

group C one year event rate

hrA

group A to group C hazard ratio

hrB

group B to group C hazard ratio

hrAB

group AB to group C hazard ratio

mincens

minimum censoring time

maxcens

maximum censoring time

dig

number of decimal places to roundDown the critical value to

alpha

two-sided significance level

niter

number of times we call pmvnorm to average out its randomness

abseps

abseps setting in the pmvnorm call

corAa

correlation between the overall A and simple A log hazard ratio estimates

corAab

correlation between the overall A and simple AB log hazard ratio estimates

coraab

correlation between the simple A and simple AB log hazard ratio estimates

Value

events

expected number of events

evtprob

event probabilities for the C, A, B, and AB groups, respectively

powerEA3overallA

Equal Allocation 3's power to detect the overall A effect

powerEA3simpleA

Equal Allocation 3's power to detect the simple A effect

powerEA3simpleAB

Equal Allocation 3's power to detect the simple AB effect

powerEA3anyA

Equal Allocation 3's power to detect the simple A or AB effects

powerPA2overallA

Proportional Allocation 2's power to detect the overall A effect

powerPA2simpleAB

Proportional Allocation 2's power to detect the simple AB effect

powerEA2simpleA

Equal Allocation 2's power to detect the simple A effect

powerEA2simpleAB

Equal Allocation 2's power to detect the simple AB effect

powerA

power to detect the overall A effect at the two-sided alpha level

powerB

power to detect the overall B effect at the two-sided alpha level

References

Leifer, E.S., Troendle, J.F., Kolecki, A., Follmann, D. Joint testing of overall and simple effect for the two-by-two factorial design. (2019). Submitted.

Slud, E.V. Analysis of factorial survival experiments. Biometrics. 1994; 50: 25-38.

See Also

eventProb, crit2x2, lgrkPower strLgrkPower, powerEA3, powerPA2, powerEA2

Examples

# Corresponds to scenario 4 in Table 2 from Leifer, Troendle, et al. (2019).
n <- 4600
rateC <- 0.0445
hrA <- 0.80
hrB <- 0.80
hrAB <- 0.72
mincens <- 4.0
maxcens <- 8.4

fac2x2design(n, rateC, hrA, hrB, hrAB, mincens, maxcens, dig = 2, alpha = 0.05, niter = 1)
# $events
# [1] 954.8738

# $evtprob
# probC     probA     probB    probAB
# 0.2446365 0.2012540 0.2012540 0.1831806

# $powerEA3overallA
# [1] 0.5861992

# $powerEA3simpleA
# [1] 0.5817954

# $powerEA3simplAB
# [1] 0.9071236

# $powerEA3anyA
# [1] 0.7060777
# $powerPA2overallA
# [1] 0.6582819

# $powerPA2simpleAB
# [1] 0.9197286

# $powerEA2simpleA
# [1] 0.6203837
#
# $powerEA2simpleAB
# [1] 0.9226679

# $powerA
# [1] 0.7182932

# $powerB
# [1] 0.7182932