MEDISGRPS: a clinically based approach to classifying hospital patients at admission.

The Medical Illness Severity Grouping System--called MEDISGRPS--is an admission-oriented patient severity grouping system that uses objective, key clinical findings to place patients in one of five severity groupings. Data from five hospitals indicate that severity level at admission is an important predictor of resource use, is essential for analysis of patients who deteriorate and/or respond poorly to therapy, and is useful to further specify DRGs. Measures of effectiveness and efficiency using MEDISGRPS are suggested.