Table 4.

Intra-observer reliability of the classification systems

	Observer 1	Observer 2	Observer 3	Observer 4	Observer 5
Traditional Tönnis Classification System	κ = 0.883	κ = 0.578	κ = 0.780	κ = 0.884	κ = 0.907
Dichotomized Tönnis Classification System	κ = 0.949	κ = 0.948	κ = 0.521	κ = 0.848	κ = 0.948
Binary Tönnis Classification System	κ = 0.948	κ = 0.948	κ = 0.9	κ = 0.948	κ = 0.892