Serious Safety Event Rate (SSER)

What Is a Serious Safety Event (SSE)?

A Safety Event is a situation where best or expected practice does not occur. If this is followed by serious harm to a patient, then we call it a “Serious Safety Event (SSE)”.

Why Do We Measure?

  • When an SSE occurs, we mobilize all our resources to understand what happened and why it happened.

  • By studying what happened and why we can best determine how to prevent it from happening again.

  • By keeping track of our rate of Serious Safety Events, we can make sure we are improving the safety of our patients, we can compare ourselves to other hospitals, and we can learn from other hospitals on the same patient safety journey.

  • The ultimate goal of measuring is to eliminate all Serious Safety Events. That is the basis of our Zero Hero patient safety program.

How Do We Measure?

  • Each month we record the number of Serious Safety Events that have occurred, if any. This number is divided by patient days, so that we can compare to other hospitals. Then we use the average rate for that month plus the previous 11 months to get a 12 month rolling average.

  • When an event is identified as a possible SSE, we assign a Root Cause Analysis (RCA) team to thoroughly investigate. An executive sponsor from the Office of the CEO oversees the meetings. Assisted by dedicated people from our Quality Improvement Department, experts and leaders from the areas involved with the event review a detailed timeline and the results of many hours of interviews of people directly involved with the event.

  • Based on this information, the RCA team makes recommendations that will prevent a repeat of the event.

How Are We Improving?

  • When we implemented our Zero Hero patient safety program in the fall of 2009, we began to see an increase in the SSER. This increase is seen in all hospitals that get serious about patient safety because a focus on safety causes a heightened awareness which results in an increase in reported events. So this initial upswing in events is an apparent increase as employees better report all safety related incidents.

  • However, once we reached our peak in early 2010, the SSER has steadily gone down to the point we have seen an 82% decrease. The number of days between SSEs has improved dramatically from every 11 days to current rate (see SSER chart).

 SSER graph

How Do I Read This Chart?

We report our data using what is known as a control chart. There are four elements on the chart. 1) The blue diamonds: these are the actual data points for each month. They depict the event rate as defined on the vertical axis. 2) and 3): The dotted red lines: these are the upper and lower control limits. They are scientifically calculated to represent the statistical range within which normal random variation occurs in a stable system. 4) The solid red line. This is the average of the blue diamonds for that time frame. As long as the blue diamonds are within the dotted red lines, the system being measured is a stable one. There are certain patterns of blue diamond configuration (e.g. diamonds outside the control limits), that mean something in the system has changed. This is called special cause variation and will usually involve a deeper investigation as to why the new pattern of variation. Each control chart contains an arrow which indicates the desired change direction. For most harm events, the desired direction is down (i.e. less harm is better). For other measures (compliance rates, days between harm events) the desired direction is up.