Type: Package
Title: Single to Double Arm Transition Design for Phase II Clinical Trials
Version: 1.0
Date: 2017-08-21
Author: Haolun Shi and Guosheng Yin
Maintainer: Haolun Shi <shl2003@connect.hku.hk>
Description: The package is used for calibrating the design parameters for single-to-double arm transition design proposed by Shi and Yin (2017). The calibration is performed via numerical enumeration to find the optimal design that satisfies the constraints on the type I and II error rates.
License: GPL-2 | GPL-3 [expanded from: GPL (≥ 2)]
Imports: Rcpp (≥ 0.12.7)
LinkingTo: Rcpp
NeedsCompilation: yes
Packaged: 2017-08-22 02:16:17 UTC; ra3
Repository: CRAN
Date/Publication: 2017-08-22 07:09:44 UTC

Parameter Calibration

Description

Calibrate the design parameters for the Single-to-double Arm Transition Design

Usage

findparameter(p0,p1,alpha1,beta1,alpha2,beta2)

Arguments

p0

The minimally required level for the response rate to be clinically meaningful.

p1

The desirable target rate.

alpha1

The type I error rate in the first stage.

beta1

The type II error rate in the first stage.

alpha2

The type I error rate in the second stage.

beta2

The type II error rate in the second stage.

Value

n1

The number of subjects in the experimental arm in the single-arm stage.

n2

The number of subjects in each arm in the double-arm stage.

r1

The minimum number of responses to achieve in the single-arm stage in order for the trial to proceed into the next stage.The number of responses observed at the end of single-arm stage should be greater than or equal to r1 for the trial to proceed.

ess0

The expected sample size under the null hypothesis.

ess1

The expected sample size under the alternative hypothesis.

asn

The average sample number taken as the average of ess0 and ess1.

Author(s)

Haolun Shi <shl2003@connect.hku.hk>,
Guosheng Yin <gyin@hku.hk>

References

Shi H., Yin G. (2017), START: Single-to-double Arm Transition Design for Phase II Clinical Trials. Submitted.

Examples

findparameter(p0=0.2,p1=0.5,alpha1=0.25,beta1=0.05,alpha2=0.2,beta2=0.25)

Rejection Probability Calculation

Description

Calculate the probability of rejecting the null hypothesis at the end of the second stage in the Single-to-double Arm Transition Design

Usage

rejectprob(pe,ps,n1,n2,r1,z)

Arguments

pe

The response rate of the experimental arm.

ps

The response rate of the standard arm.

n1

The number of subjects in the experiemntal arm in the single-arm stage.

n2

The number of subjects in each arm in the double-arm stage.

r1

The minimum number of responses to achieve in the single-arm stage in order for the trial to proceed into the next stage.

z

The threshold value for the Z test, i.e., the Z statistic should be greater than z in order to reject the null hypothesis at the end of the second stage.

Value

n1

The number of subjects in the experiemntal arm in the single-arm stage.

n2

The number of subjects in each arm in the double-arm stage.

r1

The minimum number of responses to achieve in the single-arm stage in order for the trial to proceed into the next stage.The number of responses observed at the end of single-arm stage should be greater than or equal to r1 for the trial to proceed.

ess0

The expected sample size under the null hypothesis.

ess1

The expected sample size under the alternative hypothesis.

asn

The average sample number taken as the average of ess0 and ess1.

Author(s)

Haolun Shi <shl2003@connect.hku.hk>,
Guosheng Yin <gyin@hku.hk>

References

Shi H., Yin G. (2017), START: Single-to-double Arm Transition Design for Phase II Clinical Trials.

Examples

rejectprob(pe=0.2,ps=0.4,n1=20,n2=40,r1=10,z=qnorm(0.9))