A SAS(®) macro implementation of a multiple comparison post hoc test for a Kruskal-Wallis analysis

Alan C Elliott; Linda S Hynan

doi:10.1016/j.cmpb.2010.11.002

A SAS(®) macro implementation of a multiple comparison post hoc test for a Kruskal-Wallis analysis

Comput Methods Programs Biomed. 2011 Apr;102(1):75-80. doi: 10.1016/j.cmpb.2010.11.002. Epub 2010 Dec 10.

Authors

Alan C Elliott¹, Linda S Hynan

Affiliation

¹ Department of Clinical Sciences, Division of Biostatistics, UT Southwestern Medical Center, Dallas, TX 75390-8822, United States. alan.elliott@utsouthwestern.edu

PMID: 21146248
DOI: 10.1016/j.cmpb.2010.11.002

Abstract

The Kruskal-Wallis (KW) nonparametric analysis of variance is often used instead of a standard one-way ANOVA when data are from a suspected non-normal population. The KW omnibus procedure tests for some differences between groups, but provides no specific post hoc pair wise comparisons. This paper provides a SAS(®) macro implementation of a multiple comparison test based on significant Kruskal-Wallis results from the SAS NPAR1WAY procedure. The implementation is designed for up to 20 groups at a user-specified alpha significance level. A Monte-Carlo simulation compared this nonparametric procedure to commonly used parametric multiple comparison tests.

MeSH terms

Algorithms
Analysis of Variance
Mathematical Computing
Monte Carlo Method
Software*
Statistics, Nonparametric*