Endorsement of the FOUR Score for Consciousness Assessment in Neurosurgical Patients

The Full Outline of UnResponsiveness (FOUR) score was previously developed for neurological assessment, but has not been validated in neurosurgical patients, so was compared to the Glasgow Coma Scale (GCS) in practice. Four groups of raters, expert clinicians, novice clinicians, experienced nurses, and inexperienced nurses, assessed 64 patients in awake, drowsy, stuporous, and comatose conditions to investigate rater reliability. Then, 36 patients were evaluated by 1 expert clinician and 1 from the other groups randomly to test the difference. Spearman's correlation was used to find the correlation between both scores from 68 patients. The estimation of FOUR score cut points was validated by weighted kappa compared with the GCS to establish the risk prognosis. Score feasibility was analyzed by nonparametric test. Intraclass correlation in each group was over 0.9, with no difference between expert and inexperienced raters (p > 0.05). The correlation was 0.78. Low, intermediate, and high risk prognosis were associated with 0-7, 8-14, and 15-16 FOUR scores with kappa of 0.92. The feasibility of the FOUR score was lower than that of the GCS (p < 0.01). The FOUR score is reliable and valid for consciousness evaluation with some consequences for practicability. Extensive implementation would increase familiarity.