Table 1.

MRI measurements by 3 observers (A, B, and C) of minimal dural sac area (mm²) in a randomly selected subset of 20 patients

A	B	C
40	47	38
17	58	32
42	30	40
18	29	26
35	23	29
31	38	30
17	40	33
66	55	48
38	38	30
55	36	35
30	48	32
43	53	70
56	46	61
15	36	25
54	50	47
44	34	32
62	45	58
22	43	37
82	68	76
65	78	77