rci {MDMA}

Reliable change index

Description

rci computes the reliable change index according to Jacobson and Truax (1992).

Usage

rci(x1, x2, rxx)

Arguments

x1

prescore.

x2

postscore, same length as x1.

rxx

internal consistency statistic.

Value

rci returns a vector of length(x1) with reliable change index scores.

Author(s)

Mathijs Deen

References

• Jacobson, N.S., & Truax, P. (1992). Clinical significance: a statistical approach to defining meaningful change in psychotherapy research. Journal of Consulting and Clinical Psychology, 59, 12-19.

Examples

library(MASS)
set.seed(1)
q <- mvrnorm(n=120, mu=c(40, 50), Sigma = matrix(c(56.25,45,45,56.25), ncol = 2), empirical = TRUE)
cbind(q, rci(q[,1], q[,2], .8), rci(q[,1], q[,2], .8) > 1.96)