According to a recent study of 43,853 hospital stays:

• 10.4% of the hospital stays were for observation • Mean observation length of stay was 33.3 hours, with 44.4% of stay durations less than 24 hours and 16.5% more than 48 hours • Observation care had a negative margin per stay (−$331) • The inpatient margin per stay was positive (+$2163) Source: "Hospitalized but Not Admitted: Characteristics of Patients With “Observation Status” at an Academic Medical Center," JAMA Internal Medicine, abstract only, November 25, 2013, http://archinte.jamanetwork.com/article.aspx?articleID=1710122&utm_source=Silverchair%20Information%20Systems&utm_medium=email&utm_campaign=ArchivesofInternalMedicine%3ANewIssue11%2F25%2F2013