A comparison of APACHE II and a clinical sickness score. A study of 97 consecutive admissions to a district general hospital intensive care unit.

The aim of this study was to compare the predictive power of a simple illness severity score (Clinical Sickness Score) to that of APACHE II in a District General Hospital intensive therapy unit. A prospective comparison was carried out on 97 consecutive adult patients whose severity of illness was scored one hour after admission using both the Clinical Sickness Score and APACHE II. Intensive Therapy Unit and hospital outcomes were recorded for each patient. The Clinical Sickness Score and APACHE II identified survivors and nonsurvivors with similar power (p less than 0.001). There was a highly significant correlation between the two scoring systems for hospital survivors and nonsurvivors together (r = 0.5418, r2 = 0.28, p = less than 0.0001) and for hospital survivors alone (r = 0.6102, r2 = 0.37, p = 0.0001). Correlation for hospital nonsurvivors was not significant (r = 0.1629, r2 = 0.027, p = 0.3134). The positive predictive values of APACHE II were between 5% and 10% more sensitive than the Clinical Sickness Score for hospital outcome. Admission Clinical Sickness Score and APACHE II scores had similar predictive power in this study.