The process capability study evaluates the inherent variability of a process and compares it to the specified tolerance limits. By analyzing the process data, including the upper and lower specification limits, the study provides insights into the process's performance. It considers both the process mean (centering) and the process spread (variability) to determine if the process is capable of meeting customer expectations.
The study involves the following steps:
* Data Collection: Gather data on the process output (e.g., product dimensions, defect counts, etc.).
* Calculate Process Capability Indices (Cp, Cpk):
* Cp: Measures the process spread relative to the specification width. A higher Cp indicates better capability.
* Cpk: Accounts for process centering. It considers how well the process mean aligns with the target value. A higher Cpk indicates better capability.
* Interpretation:
* If both Cp and Cpk are greater than 1, the process is capable of meeting specifications.
* If only Cp is greater than 1, the process may not be centered correctly.
* If only Cpk is greater than 1, the process may be centered but not well spread.
* If both Cp and Cpk are less than 1, the process needs improvement.
* Process Improvement: Based on the results, take corrective actions to enhance process capability.
In summary, the process capability study helps estimate the expected percentage of defective material by assessing the process's ability to produce conforming products within specified limits. It is a valuable tool for quality managers and organizational excellence professionals12.
:
ASQ Certified Manager of Quality/Organizational Excellence (CMQ/OE) Body of Knowledge. Retrieved from ASQ.
ASQ Certified Manager of Quality/Organizational Excellence Certification Brochure. Retrieved from ASQ.

Focus group studies are a qualitative research method that gathers feedback from customers about their perceptions and experiences with a product or service. This method is particularly useful for measuring perceived quality because it allows for in-depth discussions and insights into customer attitudes and satisfaction, which are not easily quantifiable through other means such as failure reports or capability tests.
While analyzing field failure reports, reviewing capability tests, and monitoring warranty claims can provide data on the actual quality and reliability of a product, they do not capture the customer's subjective experience and perception of quality. Focus group studies enable a company to understand the customer's voice, which is essential for measuring and improving perceived quality.
:
ASQ Certified Manager of Quality/Organizational Excellence Handbook1.
ASQ Manager of Quality/Organizational Excellence Certification information2.

Return on Investment (ROI) is a widely used financial metric that measures the profitability of an investment.
It is expressed as a percentage and is calculated by dividing the net gain (profit) from an investment by the cost of that investment. The formula for ROI is:
[ ROI = \frac{{\text{{Net Gain from Investment}}}}{{\text{{Cost of Investment}}}} \times 100% ] In the context of quality improvement projects, ROI provides a way to assess the financial impact of process enhancements, quality initiatives, or other improvement efforts. By comparing the ROI of quality improvement projects with other company investments, organizations can prioritize and allocate resources effectively. A positive ROI indicates that the project generated more value than its cost, while a negative ROI suggests that the investment did not yield sufficient returns.
:
ASQ Certified Manager of Quality/Organizational Excellence Certification Handbook. Retrieved from ASQ2.