In Acute and Ambulatory Nursing Care, you will most likely be using internal statistics for both your baseline data and your outcome indicators. Check with your quality or information management/analytics departments to gather data on the issue/problem you are approaching. Below are some resources if your wish to compare your organization's outcomes to others.
healthcare statistics on hospital inpatient stays, emergency department visits, and ambulatory surgeries. Topics include medical conditions treated, procedures performed, patient populations served, and quality of care.