Inter-Rater Reliability of the International Standards to Document Remaining Autonomic Function after Spinal Cord Injury

Abstract

The autonomic nervous system can be profoundly affected after spinal cord injury (SCI). Despite its importance to quality of life, autonomic function is rarely systematically assessed in the clinical setting. The International Standards to Document Remaining Autonomic Function after Spinal Cord Injury (ISAFSCI) is an assessment designed to determine which autonomic functions are intact, impaired, or lost after SCI. The psychometric properties of the ISAFSCI have not yet been reported. The objective of this study was to describe the inter-rater reliability of the ISAFSCI. Participants with chronic traumatic SCI (greater than 1 year) able to remain on the same medications for the study period and communicate clearly with the assessor were recruited for the study. A standard protocol minimized variation between the sites. During the first assessment, neurologic examination (ISNCSCI) was performed and ISAFSCI completed. After 10–14 days, the ISAFSCI was repeated. Inter-rater reliability was calculated using percentage agreement, kappa, and weighted kappa statistics. Participants (n = 48) had an average age of 45 ± 12 years. Forty-one (85.4%) were male, 38 (79.2%) had a SCI at or above the T6 level, 24 (50.0%) had a complete SCI. Inter-rater reliability within the general autonomic component was moderate with kappa values ranging 0.41–0.6 (p < 0.05). Within the Lower Urinary Tract, Bowel, and Sexual Function component, agreement was good-strong with weighted kappa values 0.62–0.88 (p < 0.05). Given the results, we conclude that the ISAFSCI can be considered to have at least moderate and up to strong inter-rater reliability, especially in the bladder, bowel, and sexual function component of the assessment.