PHYSIOLOGICAL SCORING SYSTEMS AND AUDIT

Scoring systems designed to rate the severity of an illness are being used for comparison of hospital units to identify different standards of care and to allocate resources. One such scoring system is the Acut e Physiology and Chronic Health Evaluation (APACHE) system which is de signed to assess the severity of illness of patients in intensive care units (ICUs). It is widely assumed that different ICUs can be compare d by the ratio of actual mortality to that predicted by the APACHE sco re. However, we suggest that the use of physiological data that can be influenced by medical and nursing intervention should not be used for audit. For example, by good care a patient may be made less severely ill and, therefore, may have a lower actual mortality while, at the sa me time, accumulating only a low APACHE score with low predicted morta lity. This patient could have, therefore, the same mortality ratio as a patient treated inappropriately, who may have a higher actual mortal ity and a high APACHE score with greater predicted mortality. Paradoxi cally, the very accuracy of these scoring systems for assessing the se verity of illness precludes their use for comparison and audit.