Top 10 Reasons for Visit and Discharge Diagnoses for Patients evaluated in Observation, 2001–2008.

‡All visit counts were rounded to the closest thousand.*This is the ED observation proportion, the proportion of all ED visits with a disposition to observation.**This is the ED admission proportion: the proportion of patients admitted for inpatient services of all ED patients.†This is the admission from observation proportion; the proportion of ED observation visits subsequently admitted to inpatient status.¥ This is the Observation to Admission Ratio: the ratio of all ED visits with an initial disposition to observation to all patients with a disposition to observation or inpatient admission.$ Clinical Classificatino System (16)