Table 2.

Concordance among the checkerboard and the three gradient diffusion methods, using the SBPI criteria (n = 70).

	Checkerboard					Categorical	Kappa Statistics
Gradient Method	0–2	2–50	50–100	>100	Total	Agreement (%)	K	p-Value
Cross						82.86	0.662	<0.001
0–2	30	7	0	0	37
2–50	4	28	0	1	33
50–100	0	0	0	0	0
>100	0	0	0	0	0
Direct overlay						67.14	0.356	0.001
0–2	31	19	0	0	50
2–50	3	16	0	1	20
50–100	0	0	0	0	0
>100	0	0	0	0	0
MIC:MIC						77.14	0.556	<0.001
0–2	30	10	0	0	40
2–50	4	24	0	1	29
50–100	0	1	0	0	1
>100	0	0	0	0	0