Supplemental Material: BFCRS
The Bush Francis Catatonia Rating Scale (BFCRS) was the tool used to
ascertain catatonia signs in study patients. The first 14 items of the BFCRS make up the Bush Francis Catatonia Screening Instrument (BFCSI), which is typically used by psychiatrists to screen for catatonia, with >2 items present, indicating a positive screen for catatonia. The BFCRS was used as the primary assessment tool for catatonia as it screens for a broader array of catatonia signs than the DSM-5 (23 versus the 12 in the DSM). Of the 23 items under evaluation, 16 items are scored on a scale of 0 to 3 (0, 1, 2, 3); with a score of 0 expressing absence of the sign and a score of 3 expressing the presence of the sign in its most severe form. Seven items are scored denoting either 0 or 3 (absent or present). We allowed catatonia features to be scored as “unable to assess”, as the study investigators suspected a priori that some catatonia signs might be unable to be assessed due to the patient’s critical illness (e.g., inability to assess mutism in an intubated and sedated patient). Due to an a priori concern that certain features of critical illness might mimic catatonia (e.g., whispering following a recent extubation being mistaken for mutism) the examiners were instructed to score each catatonia sign present only if there was no clear medical explanation for the presence of that sign. For example, patients were not rated for immobility/stupor if under sedation, but were assessed for other features of catatonia on an individual basis.
