getwm: Obtain the working models for use in the partial order...

In pocrm: Dose Finding in Drug Combination Phase I Trials Using PO-CRM

Description

getwm returns a matrix of skeleton values corresponding to the possible orderings of the toxicity probabilities in a Phase I trial of combined drugs for use in the partial order continual reassessment method (PO-CRM).

Usage

getwm(orders, skeleton)

Arguments

orders	A matrix specifying the possible orderings of the combinations with regards to their toxicity probabilities.
skeleton	A vector of values for the initial guesses of toxicity probabilities. The location of these values will be adjusted to correspond to the orderings specified by orders.

Details

Based on the matrix of possible orderings, the skeleton values are adjusted to correspond to the possible orderings of the toxicity probabilities. See Table 4 of Wages, Conaway and O'Quigley (2011).

Value

alpha

A matrix of skeleton values corresponding to the possible orderings of the toxicity probabilities specified by orders.

References

Wages, Conaway and O'Quigley (2011). Dose-finding design for multi-drug combinations. Clinical Trials 8(4): 380-389.

Examples

#All specifications refer to example in Wages, Conaway and O'Quigley (2011).

#Specify the possible orderings from Table 2
orders<-matrix(nrow=8,ncol=8)
orders[1,]<-c(1,2,3,4,5,6,7,8)
orders[2,]<-c(1,3,2,4,5,6,7,8)
orders[3,]<-c(1,2,3,5,4,6,7,8)
orders[4,]<-c(1,2,3,4,5,7,6,8)
orders[5,]<-c(1,3,2,5,4,6,7,8)
orders[6,]<-c(1,3,2,4,5,7,6,8)
orders[7,]<-c(1,2,3,5,4,7,6,8)
orders[8,]<-c(1,3,2,5,4,7,6,8)

#Specify the skeleton values provided in Table 4.
skeleton<-c(0.01,0.03,0.10,0.20,0.33,0.47,0.60,0.70)

getwm(orders,skeleton) 

pocrm documentation built on Sept. 8, 2021, 5:08 p.m.