Saller T, et al. - Researchers examined 543 patients (mean age (SD) 52 (18) years) in the post-anaesthesia care unit in a tertiary German medical centre, to assess the performance of the 4 A's test (4AT). The participants were screened using the Nurse Delirium Screening Scale and a new German translation of the 4AT at the point of discharge from the post-anaesthesia care unit. The 4AT yielded 95.5% sensitivity and 99.2% specificity, with the area under the receiver operator characteristic curve of 0.998. Sensitivity and specificity of 27.3% and 99.4%, respectively, were displayed by the Nursing Delirium Screening Scale, with an area under the curve of 0.761. For delirium detection in the post-anaesthesia care unit, the 4AT was identified as an effective and robust tool.