Stroke Severity Score based on Six Signs and Symptoms The 6S Score: A Simple Tool for Assessing Stroke Severity and In-hospital Mortality

BACKGROUND AND PURPOSE Ascertaining stroke severity and predicting risk of in-hospital mortality is crucial to advise patients and families about medical decisions. We developed and tested the validity of a new stroke score, the 6S Score (Stroke Severity Score based on Six Signs and Symptoms), for quantifying ischemic stroke severity and predicting in-hospital mortality. METHODS We prospectively assessed 210 consecutive acute ischemic stroke patients. The cohort was further divided into a derivation (n=120) and a validation (n=90) sample. From a total of 10 stroke signs and symptoms, we selected those with likelihood ratio's P<0.005. We tested the validity of the score for predicting in-hospital mortality by using receiver operating characteristic curves. We used a scatterplot and the Spearman's test to evaluate the correlation between the 6S Score and the National Institutes of Health Stroke Scale as a marker of stroke severity. We used principal component and exploratory factor analyses for assessing qualitative aspects of the 6S Score. RESULTS The C statistic for in-hospital mortality was 0.82 for the 6S Score and 0.86 for the National Institutes of health Stroke Scale, respectively, with no significant differences between each other (P=0.79). The correlation between both scores was strong (Spearman's rho 0.68, P<0.001). The factor analyses showed a good balance between left/right hemispheres and anterior/posterior circulations. CONCLUSIONS The 6S Score may constitute a tool for easily assessing stroke severity and predicting stroke mortality. Further research is needed for further assessing its external validity.