QualInt (version 1.0.0)

ibga: Extract IBGA results from a "qualint" object

Description

Extract the testing results of IBGA from a "qualint" object. Only available when test = "IBGA". Produce an error signal if test = "LRT".

Usage

ibga(x)

Arguments

x

a qualint object

Value

A numeric matrix depending on scale (see above).

Details

This function extracts the results related with the IBGA graph from a "qualint" object, which is a matrix which contains the estimating and testing information of the treatment effects (see examples). FOr continuous responses, it is the mean difference. For binary responses, it is the risk difference, relative risk or odds ratio. For survival responses, it it hazard ratio.

References

Gail and Simon (1985), Testing for qualitative interactions between treatment effects and patient subsets, Biometrics, 41, 361-372.

Pan and Wolfe (1993), Tests for generalized problems of detecting qualitative interaction, Technical Report No. 526, Department of Statistics, The Ohio State University.

Pan and Wolfe (1997), Test for qualitative interaction of clinical significance, Statistics in Medicine, 16, 1645-1652.

See Also

coef.qualint

Examples

ynorm <- rnorm(300)
trtment <- sample(c(0, 1), 300, prob = c(0.4, 0.6),
                  replace = TRUE)
subgrp <- sample(c(0, 1, 2), 300, prob = c(1/3, 1/3, 1/3),
                 replace = TRUE)
test1 <- qualint(ynorm, trtment, subgrp)
ibga(test1)