A Russian validation study of the Coma Recovery Scale-Revised (CRS-R)

ABSTRACT

Introduction: The aim of the study was to develop and validate a Russian adaptation of the Coma Recovery Scale–Revised (CRS-R).

Subjects and methods: We evaluated 58 patients with chronic disorders of consciousness (> 4 weeks post-injury, DOC) of various etiology and two patients in a locked-in state at different stages after coma. We tested sensitivity for changes over 1 week, reliability, 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).

Results: We obtained good sensitivity for changes in neurological status over week (p < 0.0001) and good test-retest reliability (r = 0.997, p < 0.0001) of the CRS-R. Inter-rater reliability was good (κ = 0.99, p < 0.001). We showed high internal consistency (α = 0.87) of the scale and good criterion validity between other scales (r = 0.597 for GCS, and r = 0.900 for FOUR). CRS-R also demonstrated a higher sensitivity in differential diagnosis of DOC, as compared to GCS, and FOUR Score (p < 0.001).

Conclusion: The results show that the Russian version of the CRS-R is a valid and sensitive tool for the evaluation of patients with chronic DOC, which can be used for differential diagnosis and for recovery assessment.

KEYWORDS:

• Disorders of consciousness
• minimally conscious state
• vegetative state
• validation
• coma recovery scale-revised

Acknowledgments

The authors highly appreciate efforts of Dr. M. A. Loskutnikov and Dr. V. A. Shandalin in recruiting patients into the study, and are thankful to Sofia Gutkin for her input in the translation of the CRS-R.

Disclosure Statement

The study is supported by Russian Science Foundation grant 16-15-00274 (E.M., L.L., J.R., N.S., and M.P.).

Additional information

Funding

This work was supported by the Russian Science Foundation [16-15-00274]