Validation of the Korean version of inflammatory Rasch‐built Overall Disability Scale in patients with inflammatory neuropathy

Abstract Background and Aims The Inflammatory Rasch‐built Overall Disability Scale (I‐RODS) is an effective activity measure for use in inflammatory peripheral neuropathy. The aim of this study was to validate the Korean version of the I‐RODS in patients with chronic inflammatory demyelinating polyneuropathy (CIDP), Guillain‐Barré syndrome (GBS), anti‐myelin‐associated glycoprotein (MAG) neuropathy, and autoimmune nodopathy. Methods A total of 120 patients underwent clinical evaluations, which included the I‐RODS, Inflammatory Neuropathy Cause and Treatment (INCAT) assessment, and Jamar grip strength (kg) measurement. Follow‐up assessments were performed for 83 patients during their regular clinic visits. To estimate the test–retest reliability of the I‐RODS, the scale was reapplied to a subset of 16 patients within 2–7 days of the initial test. Overall, reliability, validity, and responsiveness of the I‐RODS were evaluated. Results Internal consistency was good, as indicated by a person separation index of 0.966. The raw and standardized Cronbach's alpha values were both 0.974. The test–retest reliability analyzed using the intraclass correlation coefficient (ICC) was also high (ICC = 0.972). The I‐RODS showed a strong correlation with INCAT scores ( ρ = −0.81, p < .001) and a moderate correlation with grip strength ( ρ = 0.61, p < .001). Furthermore, the sensitivity for detecting clinically meaningful improvement was highest for grip strength (60.4%) followed by I‐RODS (52.1%), while for capturing deterioration, it was highest for I‐RODS (80.0%). Interpretation The Korean version of the I‐RODS is a reliable and valid tool for measuring disability in patients with inflammatory neuropathy. The I‐RODS is useful for both clinical practice and research applications.