This was a secondary analysis of a prospective observational study that enrolled ED patients 65 years or older. The original bCAM was a brief (< 2 minutes) delirium assessment that assessed for inattention by asking the patient to recite the months backward from December to July. It was modified by adding the Vigilance A (“squeeze my hand when you hear the letter ‘A’”) to the inattention assessment. The elements of the modified bCAM were performed by a research assistant (RA) and emergency physician. The reference standard for delirium was a psychiatrist assessment performed within 3 hours using Diagnostic and Statistical Manual of Mental Disorder, Fourth Edition, Text Revision criteria. All assessors were blinded to each other. Sensitivities and specificities with their 95% confidence intervals (CIs) were calculated for the RA and emergency physician.
Of the 406 patients enrolled, 50 (12%) were delirious. The modified bCAM was 82.0% (95% CI, 71.4%-92.6%) sensitive and 96.1% (95% CI, 94.0%-98.1%) specific when performed by the RA. The emergency physician's modified bCAM exhibited similar diagnostic performance.
The modified bCAM may be a feasible and accurate method for nonphysicians to assess for delirium. Future studies are needed to confirm these findings.