What is the role of the Plan-Do-Study-Act cycle in quality improvement?

• A. Plan the next test.
• B. Do the change.
• C. Study results and decide next steps.
• D. Archive the data.

Answer: (C)

The key idea is learning from what happened and deciding what to do next. In a Plan-Do-Study-Act cycle, after you implement a change (the Do phase), you carefully examine the results (the Study phase). This step is about analyzing data, seeing whether the change produced the expected effect, understanding any variation, and then deciding the next action—whether to adapt the change, run another small test with a modification, or abandon it altogether. That decision point guides the next cycle, driving continuous improvement.

The other activities—planning the next test, carrying out the change, or simply archiving data—are parts of the process or supporting tasks, but they don’t capture the core purpose of the cycle as clearly as the study-and-decide-that-next-step focus.