Reliability of the Bryce/Ragnarsson spinal cord injury pain taxonomy

Pain is a common secondary complication of spinal cord injury (SCI). However, the literature offers varying estimates of the numbers of persons with SCI who develop pain. The variability in these numbers is caused in part by differences in the classification of pain; there is currently no commonly accepted classification system for pain affecting persons after SCI. This study investigated the interrater reliability of the Bryce/Ragnarsson SCI pain taxonomy (BR-SCI-PT). The hypothesis was that, when used by physicians with minimal training in the BR-SCI-PT, it would have high interrater reliability for the categorization of reported pains.

One hundred thirty-five vignettes, each of which described a person with SCI with one or more different etiologic subtypes of pain, were evaluated by 5 groups of up to 10 physicians with SCI subspecialization (39 respondents total). Physician classifications were compared with those made by the investigators.

Of 179 pain descriptions, 83% were categorized correctly to one of the 15 BR-SCI-PT pain types; 93% were categorized correctly with respect to level (above/at/below neurological level of injury), whereas 90% were categorized correctly as being either nociceptive or neuropathic. Subjects expressed a generally high confidence in the correctness of their classifications.

Substantial interrater agreement was achieved in determining subtypes of pain within the BR-SCI-PT. The agreement was improved for categorizing within less restrictive categories (ie, with respect to the neurological level of injury and whether the pain was nociceptive or neuropathic).