Advantages:
- Strong control of Type I error with unequal sample sizes.
- More powerful than Dunn in many conditions.
Disadvantages:
- Computationally more complex.
- Less commonly available in standard software.
- It is only useful in completely random or single-factor designs.
References
Dwass, M. (1960). Some k-sample rank-order tests. In I. Olkin et al. (Eds.), Contribution1s to Probability and Statistics: Essays in Honor of Harold Hotelling (pp. 198 - 202). Stanford University Press.