An analogue approach to audit in anaesthesia.

The predicted outcome of anaesthesia and surgery was compared with the immediate outcome in 508 patients by means of two 100 mm linear analogue scales. The results were used to obtain a statistically based rule by which the anaesthetist may consistently select three groups of patients for audit: group 1, patients in whom immediate outcome of anaesthesia and surgery is worse than predicted; group 2, patients whose outcome is better than predicted; and group 3, the remaining patients. The rule, which is simply adapted to departmental audit, does not necessarily need a computer but is suited to the computer as it is numerically based.