* Reviewing the Control Chart DataThe control chart shows "Events/Bed Day" over time, with the Upper Control Limit (UCL), Lower Control Limit (LCL), and a center line (CL) marking the baseline average of the process before the intervention.
* Identifying the Impact of the New Process
* The intervention to reduce events per bed day was implemented on January 7.
* Following this date, there is a noticeable and consistent decrease in the number of events per bed day, with data points gradually moving downward.
* Eventually, the values settle well below the original center line, indicating a decreasing shift in the process.
* Differentiating Between Trends and Shifts
* A shift is characterized by a sustained change in process level, often due to a successful intervention, as seen here with lower event rates maintained over time.
* In this case, the shift is in a favorable direction, as the targeted events per bed day have reduced significantly and consistently.
* A trend would indicate a continuous movement in a direction, but this chart shows that after an initial decline, the process stabilizes at a lower rate.
* ConclusionSince the process has demonstrated a decreasing shift, indicating improvement and reduced events per bed day, the correct recommendation is to continue the process, as it appears successful in achieving the goal.
References:
* NAHQ "Statistical Process Control and Process Improvement Strategies"
* "Evaluating Shifts and Trends in Control Charts for Quality Improvement" (NAHQ, 2021)