Table 2.

Sensitivity and Specificity for Catatonia in Critical Illness at Different BFCSI^* Cut-off Points.^†

BFCSI cut-off point	Sensitivity (95% CI)	Specificity (95% CI)
BFCSI ≥2 signs	1 (0.958 – 1)	0.468 (0.423 – 0.514)
BFCSI ≥3 signs	1 (0.958 – 1)	0.65 (0.605 – 0.692)
BFCSI ≥4 signs	0.908 (0.829 – 0.953)	0.906 (0.876 – 0.929)
BFCSI ≥5 signs	0.586 (0.481 – 0.684)	0.989 (0.975 – 0.995)

^*BFCSI: Bush Francis Catatonia Screening Instrument

^†The reference standard for this comparison was ≥3 DSM 5 Criterion A items for diagnosing catatonia, as compared with the BFCSI. These data offer validation thresholds for the BFCSI as a bedside instrument that could be used by non-psychiatrists in routine ICU care depending on the desired sensitivity and specificity.