A Russian validation study of the Coma Recovery Scale-Revised (CRS-R)
Introduction: The aim of the present study was to validate a Russian adaptation of the Coma Recovery Scale-Revised (CRS-R).\n\nSubjects and methods: We evaluated 58 patients diagnosed with chronic disorders of consciousness (>4 weeks post-injury, DOC) of various etiology and two patients in a locked-in state at different time points in their post-comatose recovery. We tested sensitivity for changes over 1 week, reliability, as well as criterion validity and diagnostic sensitivity of the Russian adaptation of the CRS-R in comparison with the Russian adaptations of Full Outline of UnResponsiveness Score (FOUR), and Glasgow Coma Scale (GCS).\n\nResults: We obtained good sensitivity for changes in neurological status over one week (p<0.0001) and good test-retest reliability (r=1, p<0.0001) of the CRS-R. Inter-rater reliability for the CRS-R total score ({kappa}=0.99, p<0.001) and subscale scores was good. We showed high internal consistency (=0.87 and 0.89 for the first and second visit respectively). We also showed good criterion validity between two other standardized behavioral scales (moderate correlation with GCS, r=0.597 and high correlation with FOUR Score, r=0.900). CRS-R also demonstrated a significantly higher sensitivity in differential diagnosis of DOC, as compared to GCS, and FOUR Score (p<0.001).\n\nConclusion: The results show that the Russian version of the CRS-R is a valid and sensitive tool for the evaluation of severely brain damaged patients with chronic DOC which can be used for differential diagnosis and for the assessment of dynamic recovery.