A system (model) for developing objective estimates of the probable survival over a 180-day period of seriously ill hospitalized adults. The acronym comes from the name of the study which developed the method: “Study to Understand Prognoses and Preferences for Outcomes and Risks of Treatment”. The model uses each patient’s diagnosis, age, number of days in the hospital before study entry, presence of cancer, neurologic function, and 11 physiologic variables recorded on day 3 after study entry. The study reports that this relatively small number of readily available items of information can provide as good estimates of the probability of survival for 180 days as could physician’s estimates. Somewhat better predictions resulted from combining both the objective predictions with physicians’.