Interobserver agreement regarding characteristics of the disc herniation.

The number between brackets on the first row is the number of patients of which the observers suggested the presence of a disc herniation (on the same disc level). A en B represent the two neuroradiologists, while C represents the neurosurgeon.|--Categories were: 1) Right 2) Left 3) Right and left.¶Categories were: 1) Central zone 2) Sub-articular zone 3) Foraminal zone 4) Extra-foraminal zone.∥Categories were: 1) Disc level 2) Folded upwards 3) Folded downwards.§Categories were: 1) Large stenosing: size >75% of the spinal canal 2) Large: size 50–75% of the spinal canal 3) Average: size 25–50% of the spinal canal and 4) Small: size ‡The categories “large stenosing” and “large” were combined to one category and the categories “average” and “small” were also combined to one category.