Tukey HSD

This post hoc test (or multiple comparison test) can be used to determine the significant differences between group means in an analysis of variance setting. The Tukey HSD is generally more conservative than the Fisher LSD test but less conservative than Scheffe's test (for a detailed discussion of different post hoc tests, see Winer, 1985, pp.140-197). For more details, see the General Linear Models chapter. See also, Post Hoc Comparisons . For a discussion of statistical significance, see Elementary Concepts .