A diagram designed to help workers focus on the causes of a problem rather than the symptoms.. It is also referred to as the "Ishikawa diagram," because Kaoru Ishikawa developed it, and the "fishbone diagram," because the complete diagram resembles a fish skeleton. The diagram illustrates the main causes and subcauses leading to an effect (symptom). The cause and effect diagram is one of the "seven tools of quality" OR aTool for analyzing process dispersion.
A Cause and Effect diagram also called Ishikawa diagrams, fishbone diagrams, herringbone diagrams , or Fishikawa are causal diagrams that show the causes of a certain event -- created by Kaoru Ishikawa (1990). Common uses of the Ishikawa diagram are product design and quality defect prevention, to identify potential factors causing an overall effect. Each cause or reason for imperfection is a source of variation. Causes are usually grouped into major categories to identify these sources of variation. The categories typically include:
* People: Anyone involved with the process
* Methods: How the process is performed and the specific requirements for doing it, such as policies, procedures, rules, regulations and laws
* Machines: Any equipment, computers, tools etc. required to accomplish the job
* Materials: Raw materials, parts, pens, paper, etc. used to produce the final product
* Measurements: Data generated from the process that are used to evaluate its quality
* Environment: The conditions, such as location, time, temperature, and culture in which the process operates