Hello Saheed Matemilola ,

Generally, Tukey and Scheffé tests are more conservative. They find it harder to see differences and generally give the same result. In relation to the differences:

- In pairwise comparisons, Tukey test is based on studentized range distribution while Scheffe is based in F distribution.

- Tukey's test is very rigorous, controlling the type I error very well, but favors the type II error.

- The Scheffe test allows comparing any contrast between means and allows different number of observations per treatment.

Regards,

Mariel.

We would posit that there are no major differences.

Huberty, C. J, & Morris, J. D. (1988). A single contrast test procedure. Educational and Psychological Measurement, 48, 567-578.

Scheffe test is more flexible

Tukey is applicable when the sample size of the groups is equal.

Scheffe test has no such condition and used to identify all possible differences.