Figure 2.

Study population grouped by the number of frailty markers they reported and the proportion of patients identified as frail, vulnerable, or fit by the Clinical Frailty Scale (CFS) for each of these groups. The CFS is a nine-point frailty assessment tool that was completed by attending physicians in the intensive care unit: fit refers to patients with a CFS score of 1–3; vulnerable to the patients with a CFS score of 4; and frail to patients with a CFS score greater than 4 (see text for details).