The severity of disease measurements among Thai medical intensive care unit patients.

Since the diversity of diseases and complexities of treatment keeps on increasing, a precision of evaluation system that shows a strong and stable relationship to outcomes is needed. The APACHE II severity of disease classification system is an example that proved to be valid for large numbers of patients in different countries. Data from 334 Thai medical ICU patients were collected prospectively in order to validate the APACHE II system, and compare the findings with previous reports. Despite some differences in disease categories, the results showed close relation between APACHE II scores and the hospital mortality rate. The predictive power for death was strong with a specificity of 95% and correct prediction of 83% at the risk level of 0.5. The actual to predicted death ratio, an indicator of hospital performance, in this studied group was 1.17 and was close to the findings of most centers in USA. By providing a measure of severity of disease, APACHE II classification system can provide Thai researchers with a useful tool for clinical researches and improving the treatment of critically ill patients.