Making hospital mortality measurement more meaningful: incorporating advance directives and palliative care designations.

Accounting for patients admitted to hospitals at the end of a terminal disease process is key to signaling care quality and identifying opportunities for improvement. This study evaluates the benefits and caveats of incorporating care-limiting orders, such as do not resuscitate (DNR) and palliative care (PC) information, in a general multivariate model of mortality risk, wherein the unit of observation is the patient hospital encounter. In a model of the mortality gap (observed - expected from the baseline model), DNR explains 8% to 24% of the gap variation. PC provides additional explanatory power to some disease groupings, especially heart and digestive diseases. One caveat is that DNR information, especially if associated with the later stages of hospital care, may mask opportunities to improve care for certain types of patients. But that is not a danger for PC, which is unequivocally valuable in accounting for patient risk, especially for certain subpopulations and disease groupings.