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Multicenter Study
. 2023 Oct 5;33(10):531-535.
doi: 10.2188/jea.JE20220147. Epub 2022 Dec 23.

Development and Validation of a Novel Method for Converting the Japan Coma Scale to Glasgow Coma Scale

Mikio Nakajima  1   2   3 , Yohei Okada  3   4 , Tomohiro Sonoo  3 , Tadahiro Goto  2   3
Affiliations
Multicenter Study

Development and Validation of a Novel Method for Converting the Japan Coma Scale to Glasgow Coma Scale

Mikio Nakajima et al. J Epidemiol. .

Abstract

Background: The Japan Coma Scale (JCS) is the most frequently adopted method for evaluating level of consciousness in Japan. However, no validated method for converting the JCS to the Glasgow Coma Scale (GCS) exists. The aims of the present study were to develop and validate a method to convert the JCS to GCS.

Methods: This is a multicenter retrospective analysis involving three emergency departments (EDs) in Japan. We included all adult patients who visited the ED between 2017 and 2020. The participating facilities were divided into two cohorts-one cohort to develop a table to convert the JCS to GCS (development cohort), and the other cohort to validate the conversion table (validation cohort). The conversion table of the JCS to GCS was developed based on the median values of the GCS. The outcome was the concordance rate between the JCS and GCS.

Results: We identified 8,194 eligible patients. The development cohort included 7,373 patients and the validation cohort included 821 patients. In the validation cohort, the absolute and relative concordance rates were 80.3% (95% confidence interval, 77.4-82.9%) and 93.2% (95% confidence interval, 91.2-94.8%), respectively.

Conclusion: This study developed and validated a novel method for converting the JCS to GCS. Assuming the offset by a single category between the JCS and GCS is acceptable, the concordance rate was over 90% in the general adult patient population visiting the ED. The conversion method may assist researchers to convert JCS scores into GCS scores, which are more commonly recognized among global audiences.

Keywords: Glasgow Coma Scale; Japan Coma Scale; concordance; conversion; validation.

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Conflict of interest statement

Conflicts of interest: Author MN is a part-time employee of TXP Medical Co. Ltd. TG is the Chief Scientific Officer, TXP Medical Co. Ltd. TS is the Chief Executive Officer, TXP Medical Co. Ltd. None of the authors received any financial incentives for this work from TXP Medical Co. Ltd. TXP Medical may gain potential profit from the manuscript acceptance, such as the use of results to introduce the NEXT Stage ER system.

Figures

Figure 1.
Figure 1.. Study flowchart. JCS, Japan Coma Scale; GCS, Glasgow Coma Scale.
Figure 2.
Figure 2.. Relationship between the Japan Coma Scale and Glasgow Coma Scale in the development cohort. Data are presented as box plots. Lines in the box represent median values and box edges represent 25th to 75th percentiles.
See this image and copyright information in PMC

Comment in

References

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