Critical-to-Quality Requirements

Posted on November 6, 2009 by


Katy has been gathering data on the Voice of the Customer to guide her organization in developing a new line of cookies. She hires a company to survey 10,000 people on their cookie preferences. Gathering and organizing data about customer needs leads to Critical-to-Quality requirements (CTQ). These are the quality parameters of the product or process needed to assure that customer needs are met. For example, Katy’s survey found a large segment of customers that desire low-calorie cookies. So a CTQ could be that each cookie has 20 or fewer calories. Customer needs are often general, such as “low-calorie cookies.” The CTQ requirement translates this into something quantifiable. Katy’s customers also want “big cookies” which could be a CTQ requirement of having a diameter between three and four inches. A CTQ tree is a tool used to break down these general customer needs into specific and measureable requirements.

Posted in: Six Sigma