Validation of the use of the ROSIER scale in prehospital assessment of stroke

Aim: To determine the utility of the Recognition of Stroke in the Emergency Room (ROSIER) scale as a stroke recognition tool among Chinese patients in the prehospital setting.

Materials and methods: Compared with the Cincinnati Prehospital Stroke Scale (CPSS), emergency physicians prospectively used the ROSIER as a stroke recognition tool on suspected patients in the prehospital setting. And, the final discharge diagnosis of stroke or transient ischemic attack made by neurologists, after assessment and review of clinical symptomatology and brain imaging findings, was used as the reference standard for diagnosis in the study. Then, the ROSIER and the CPSS like sensitivity (Se), specificity (Sp), positive predictive value (PPV), negative predictive value (NPV), related coefficient (r) and Kappa value were calculated.

Results: In this study, 540 of 582 suspected stroke patients met the study criteria. The CPSS showed a diagnostic Se of 88.77% (95% confidence intervals [CI] 86.11-91.43%), Sp of 68.79% (95% CI 64.88-72.70%), PPV of 87.40% (95% CI 85.97-88.83%), NPV of 71.52% (95% CI 67.71-75.33%) and r of 0.503. Relatively, the ROSIER showed a diagnostic Se of 89.97% (95% CI 87.44-92.64%), Sp of 83.23% (95% CI 80.08-86.38%), PPV of 92.66% (95% CI 90.46-94.86%), NPV of 77.91% (95% CI 74.41-81.41%) and r of 0.584. According to the final discharge diagnosis, both the ROSIER and the CPSS were associated with the final discharge diagnosis (P < 0.05).The Kappa statistic value of the ROSIER and the CPSS were 0.718 and 0.582, respectively. However, there was no statistical significance of the positive rate between the ROSIER and the CPSS in this study (P > 0.05).

Conclusions: The ROSIER is a sensitive and specific stroke recognition tool for health providers' use among Chinese patients in the prehospital setting. However, it cannot be used to confidently rule out or identify stroke as a diagnosis. Comprehensive clinical assessment and further examination on potential stroke patients are still important and cannot be replaced. When it is difficult to objectively complete the ROSIER for patients, the CPSS could replace it in the prehospital setting.