A multicentre study of intentional behavioural responses measured using the Coma Recovery Scale-Revised in patients with minimally conscious state

Objective: To investigate which conscious behaviour is most frequently detected using the Coma Recovery Scale-Revised in patients with minimally conscious state. Design: Multicentre, cross-sectional study. Setting: One intensive care unit, 8 post-acute rehabilitation centres and 2 long-term facilities. Subjects: Fifty-two patients with established diagnosis of minimally conscious state of different aetiology. Main measures: All patients were assessed by the Coma Recovery Scale-Revised. Results: In most patients (34/52) non-reflexive responses were identified by two or more subscales of the Coma Recovery Scale-Revised, whereas in 14 patients only the visual subscale could identify cortically-mediated behaviours, and in the remaining 4 patients only the motor subscale did so. The clinical signs of intentional behaviour were most often detected by the visual subscale (43/52 patients) and by the motor subscale (31/52), and least frequently by the oromotor/verbal subscale (3/52) of the Coma Recovery Scale-Revised. This clinical pattern was observed independently from time post-onset and aetiology. Conclusions: Non-reflexive visual behaviour, identified by the visual subscale of Coma Recovery Scale-Revised, is the most frequently detected intentional sign consistent with the diagnosis of minimally conscious state, independently from aetiology and time post-onset.