Patients who are admitted to the hospital for treatment of one medical problem sometimes get other serious injuries, complications, or conditions while in the hospital, and may even die. The conditions, complications, and deaths included in the patient safety measures are usually rare, but can often be prevented if hospitals follow procedures known to keep patients safe.

Medicare reports three sets of patient safety measures on Hospital Compare:

• The Serious Complications and Deaths measures, developed by the Agency for Healthcare Research and Quality (AHRQ), provide information about how likely it is that patients will suffer from complications and deaths while in the hospital. Some of these complications and deaths might have been prevented if the hospital followed procedures based on best practices and scientific evidence.
• The Hospital Acquired Conditions measures show how often patients got certain serious conditions while in the hospital, that might have been prevented if the hospital followed procedures based on best practices and scientific evidence.
• The Healthcare Associated Infection measures are developed by Centers for Disease Control and Prevention (CDC) and collected through the National Healthcare Safety Network. They provide information on infections that occur while the patient is in the hospital. These infections can be related to devices, such as central lines and urinary catheters, or spread from patient to patient after contact with an infected person or surface. Many healthcare associated infections can be prevented when the hospitals use CDC-recommended infection control steps.