Making better decisions: construction of clinical scoring systems by the Spiegelhalter-Knill-Jones approach.

A study was carried out assessing the practical use of a simple system of scoring information which can help in making a diagnosis or establishing a prognosis in an individual patient. The system was introduced in 1984 for use in gastroenterology, but it can be employed in a wide range of medical and surgical settings. This series was concerned with predicting postoperative respiratory complications in a group of elderly surgical patients. The system combines elements from Baye's theorem and logistic regression, though no mathematical knowledge is required to apply it in clinical practice. The method by which results are presented is easy to understand, yet at the same time more complex ideas such as conflict of evidence and doubt may be embraced if the clinician so desires.