Six Sigma Green Belt Certification Practice Exam

What is a key tool used in root cause analysis within Six Sigma?

1. Histogram

2. C-chart

3. Fishbone diagram

4. Pareto chart

The correct answer is: Fishbone diagram

The Fishbone diagram, also known as the Ishikawa diagram or cause-and-effect diagram, is a vital tool in root cause analysis within Six Sigma methodology. This visual representation organizes potential causes of a problem into categories, helping teams identify, explore, and prioritize their issues systematically. By illustrating the relationship between problems and their contributing factors, the Fishbone diagram facilitates a deeper understanding of root causes, enabling more effective problem-solving strategies. The utility of the Fishbone diagram lies in its structured approach, encouraging teams to pursue thorough investigations by categorizing causes into major areas such as People, Process, Materials, Environment, and Measurement. This method promotes collaboration among team members and ensures that a wide range of potential causes is considered before moving forward with solutions. Other options, while useful tools in different aspects of Six Sigma, do not focus specifically on identifying root causes. For example, histograms are used for data visualization to show distributions; C-charts are utilized for monitoring the number of defects in a process; and Pareto charts help prioritize issues based on frequency or impact. Each of these tools has its specific application, but the Fishbone diagram is particularly suited to root cause analysis, making it the most fitting choice for this context.