MULTPERM: a computer package for the analysis of multivariate data using permutation procedures.

MULTPERM is a user-friendly C program using an exact permutation test for comparing groups when the data involve one or more response variables. The program computes the average within group distance based on a generalized distance function. Statistical significance of group differences is assessed by comparing the average distance for the observed data to the distribution of distances generated by all permutations of subjects to groups. This procedure is nonparametric and is especially appropriate if the assumptions underlying more traditional methods are not satisfied. The program was developed for personal computers and compiled using Borland's Turbo C 2.0. It should be easily ported to other platforms. An approximate test based on the beta distribution is incorporated for large samples.