The bedside confusion scale: development of a portable bedside test for confusion and its application to the palliative medicine population.

BACKGROUND: Clinical tests for confusion in medically ill patients are frequently burdensome and difficult to use. Available tests lack portability and tend to be shunned in clinical practice by physicians.
OBJECTIVE: To develop a simple, sensitive bedside test for confusion.
DESIGN: Prospective comparison study.
SETTING: An in-patient palliative medicine unit in a large urban hospital. PATIENTS: Thirty-one consecutive patients admitted to the unit. INTERVENTION: None. MEASUREMENTS: A 2-minute screening test, the Bedside Confusion Scale (BCS), which utilizes an observation of level of consciousness at the time of clinical interaction, followed by a timed task of attention, was administered to 31 consecutively admitted patients. The results were compared to a previously validated test, the Confusion Assessment Method (CAM). The BCS and the CAM were scored in standardized fashion and results of the two populations compared. Demographic and clinical characteristics of the patient population, along with the Karnofsky performance scores (KPS) and neurological findings were registered.
RESULTS: Using the CAM as the reference standard, the sensitivity of the BCS was 100%. Worsening KPS and more abnormalities on neurological examination were seen across normal (BCS = 0), borderline (BCS = 1), and abnormal (BCS >/= 2) groups (p > 0.01, trend test).
CONCLUSIONS: In an in-patient palliative medicine population, the BCS correlates with the previously validated CAM and exhibits high sensitivity, an essential quality of a useful screening test.