Delirium is a serious medical condition associated with increased mortality, longer hospital stay, increased rates of institutionalisation, and declines in post-admission functionality. Despite the prognostic utility of diagnosing delirium and its utility as an important indicator of health quality in elderly patients in developed countries, it is not routinely screened for in many busy general medical in-patient settings, especially in developing countries. Unpublished data from a recent study of general medical in-patients in Groote Schuur Hospital, Cape Town, South Africa, found that no patients admitted during an 8-week period received any formal cognitive testing or had documentation of the presence/absence of delirium in routine clinical notes. This under-recognition is largely the result of the length and complexity of available delirium diagnostic tools e.g. Mini-mental state exam (MMSE), although the perceived lack of clinical importance and conflicting results about specific treatment modalities also contribute.

The investigators recently developed the simple 4-question "RACY" delirium screening tool for use in general medical in-patients. Preliminary data show the test to be simple and effective with a sensitivity and specificity of 78% and 85% respectively using a ROC-selected cut-point of RACY≤2. The investigators hypothesis that the RACY screening tool has the potential to be a simple and effective bedside delirium diagnostic instrument for use in non-geriatric, busy general medical in-patient settings. This study is a two-centre validation study to evaluate the diagnostic accuracy of this tool.

Inclusion Criteria:

• Patients referred for admission to general medical wards (including within hospital transfer e.g. ICU discharge)
• >18 years and willing to give informed consent

Exclusion Criteria:

• Patient admitted directly to intensive care unit
• Patient refusing consent or <18 years old
• Patients unable to undergo delirium testing due to: i) Glasgow coma scale ≤ 12/15, ii) Aphasia