Selecting the highest-impact opportunity requires a tool that prioritizes issues based on their contribution to the problem.

Option A (Pareto chart): This is the correct answer. The NAHQ CPHQ study guide states, “Pareto charts use the 80/20 rule to identify the few critical issues causing the majority of problems, prioritizing high-impact opportunities” (Domain 4). For wait times, a Pareto chart can show which factors (e.g., scheduling delays) contribute most, guiding focus.

Option B (Ishikawa diagram): Ishikawa (fishbone) diagrams identify root causes, not prioritize impact.

Option C (Control chart): Control charts monitor process stability, not prioritize opportunities.

Option D (Check sheet): Check sheets collect data, not analyze or prioritize impact.

CPHQ Objective Reference: Domain 4: Performance and Process Improvement, Objective 4.3, “Use quality improvement tools to prioritize interventions,” highlights Pareto charts for prioritizing high-impact issues. The NAHQ study guide emphasizes their role in focusing resources effectively.

Rationale: Pareto charts are uniquely suited to identify the most impactful wait time issues, ensuring efficient use of improvement efforts, as per CPHQ prioritization principles.