Rating scales and prioritization in QFD

Presents some remarks about the use of rating scales in quality function deployment (QFD). Data collection and their correct interpretation are fundamental for the proper application of this tool as a support for designing activities. Particular attention is given to the critical aspects and consequences resulting from an incorrect use of rating scales. The paper illustrates how the priority rank of design characteristics can change depending on the type of scale used. Practical effects of these issues are finally shown on a real case concerning the design of a climatic control system for commercial vehicles.