Tukey's test, also known as the Tukey range test, Tukey method, Tukey's honest significance test, Tukey's HSD (honestly significant difference) test,[1] or the Tukey–Kramer method, is a single-step multiple comparison procedure and statistical test. It is used in conjunction with an ANOVA to find means that are significantly different from each other. Named after John Tukey, it compares all possible pairs of means, and is based on a studentized range distribution (q) (this distribution is similar to the distribution of t from the t-test).[2] The Tukey HSD tests should not be confused with the Tukey Mean Difference tests (also known as the Bland-Altman Test).