Table 4.

Cohen's Kappa and Cronbach's Alpha values between the three readers for the types of stenosis at PRP and EXT position.

	Cohen's Kappa
Type of stenosis	Reader 1 vs 2	Reader 1 vs 3	Reader 2 vs. 3	Cronbach's α
Central RPR/EXT	0.669/0.656 (Kubosch et al., 2015)	0.725/0.707 (Kubosch et al., 2015)	0.714/0.704 (Kubosch et al., 2015)	0.967/0.971∗∗∗
Lateral RPR/EXT	0.637/0.613 (Kubosch et al., 2015)	0.471/0.567 (Hebelka et al., 2022)	0.654/0.646 (Kubosch et al., 2015)	0.959/0.958∗∗∗
Foraminal RPR/EXT	0.488/0.535 (Hebelka et al., 2022)	0.476/0.462 (Hebelka et al., 2022)	0.600 (Kubosch et al., 2015)/0.517 (Hebelka et al., 2022)	0.924/0.917∗∗∗

Cohen's Kappa (Hebelka et al., 2022): 0.4–0.6 moderate agreement (Kubosch et al., 2015), 0.6–0.8 substantial agreement (Madsen et al., 2008), ≥0.8 almost perfect agreement.

Cronbach's Alpha: ∗0.7–0.8 acceptable, ∗∗0.8–0.9 good, ∗∗∗ ≥0.9 excellent.