Quality by Design

Quality is largely determined by decisions made in the early planning phases of products and processes. A particularly powerful technique for making optimal design decisions is the statistically designed experiment introduced in Chap. 5 . This chapter covers the basics of experimental designs in the context of engineering and economic optimization problems. Taguchi’s loss function, signal-to-noise ratios, factorial models, and orthogonal arrays are discussed using case studies and simple examples. A special section is dedicated to the application of quality by design (QbD) in the pharmaceutical industry. QbD is supported internationally by the International Conference on Harmonization of Technical Requirements for Registration of Pharmaceuticals for Human Use (ICH) and by the Food and Drug Administration (FDA).