A (Very) Brief Note on Some Quality Tools

Abstract

This note offers a brief overview of two techniques used in continual improvement programs: fishbone (Ishikawa) diagrams and Pareto charts. Excerpt UVA-OM-1543 Jan. 6, 2016 A (Very) Brief Note on Some Quality Tools Perhaps the most common performance assessment question about a service or manufacturing process is “Why can't we get the process to produce the quality requirements expected by the customer?” The first step in answering that question and improving the quality of the output is to figure out why such process observations might have actually occurred. Ishikawa diagrams, also known as fishbone diagrams, allow focused brainstorming around key categories of potential causes—people, machines, materials, and environment. Pareto diagrams take multiple identified possible causes for a quality problem and rank them from most common to least common cause, based on how often the problem resulted due to each specific cause. Exhibit1 and Exhibit 2 illustrate a fishbone diagram and a Pareto diagram, respectively, for evaluating transaction time for a bank teller process that has been performing below customer expectations. See Table1 for typical fishbone diagram categories. Another tool, the “five whys” exercise, consists of repeatedly asking “why” until the root cause of a problem is identified. These visual and commonsense tools can help tremendously in identifying causes and determining which to act on first. Identifying and eliminating problem-causing factors helps develop a consistent, predictable process and aids in improving the quality of the output. . . .