A validation of the Polish version of the Coma Recovery Scale-Revised (CRSR)

ABSTRACT

Primary objective: The aim of this study was to determine the validity of the Polish version of the Coma Recovery Scale—Revised (CRS-R).

Methods and design: Two trained raters, A and B, administered CRS-R on a group of 20 patients with severe brain injury (median age ± SD, 38.0 ± 14.39 years). Both rater A and rater B completed their assessment on day 1, and rater A repeated their assessment on day 2. Inter-rater and test-retest reliability were evaluated with an intra-class correlation coefficient and Spearman rank correlation. Internal consistency was estimated with Cronbach’s α. Agreement in diagnostic impression was determined using Cohen’s κ.

Results: Inter-rater reliability for CRS-R total scores and test-retest reliability was excellent: (ρ = 0.76, p < 0.001) and (ρ = 0.92, p < 0.001), respectively. Inter-rater diagnostic agreement was good (κ = 0.72, p < 0.001). Inter-rater reliability for subscales was fair to excellent. Internal consistency was excellent (Cronbach’s α = 0.85).

Conclusion: The Polish version of CRS-R can be administered reliably by trained raters and can successfully differentiate between vegetative state (VS), minimally conscious (MCS), and patients emerging from a minimally conscious state (EMCS).

KEYWORDS:

• Assessment scale
• coma recovery scale-revised
• disorders of consciousness
• minimally conscious state
• vegetative state
• consciousness

Declaration of Interest

The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper

Acknowledgments

We thank Dr Joseph T. Giacino (original author of the CRS-R) and his team at the Spaulding Rehabilitation Hospital (Boston, MA, USA) for their feedback on the translation of the scale. We also thank Karolina Kowal and Marlena Topolska-Skowrońska for their assistance in patient selection and arrangement of the study. We greatly appreciate language editing kindly provided by Megha Anil.

Funding

All authors were supported by an OPUS grant from the National Science Centre of Poland (2013/11/B/HS6/01242) and Urszula Górska was supported by ETIUDA grant from the National Science Centre of Poland (2016/20/T/HS6/00233).

Additional information

Funding

All authors were supported by an OPUS grant from the National Science Centre of Poland (2013/11/B/HS6/01242) and Urszula Górska was supported by ETIUDA grant from the National Science Centre of Poland (2016/20/T/HS6/00233).