The Seven Basic Quality Tools is a designation given to a fixed set of graphic techniques identified as the most useful in solving problems related to quality. They are called basic because they are suitable for people with little formal training in statistics and because they can be used to solve the vast majority of quality issues.
The seven tools are:
• Cause and effect diagram (also known as "fishbone" or Ishikawa diagram)
• Check sheet
• Control chart
• Histogram
• Pareto chart
• Dispersion diagram
• Stratification (alternatively, flow chart or execution diagram)
The designation emerged in post-war Japan, inspired by Benkei's seven famous weapons. It was possibly introduced by Kaoru Ishikawa who in turn was influenced by a series of lectures. W. Edwards Deming had given to Japanese engineers and scientists in 1950. At that time, companies that had begun to train their workers in quality control Statisticians found that the complexity of the subject intimidated the vast majority of its workers and reduced training to focus mainly on simpler methods that are enough for most quality issues. The Seven Basic Tools are in contrast to more advanced statistical methods such as survey sampling, acceptance sampling, statistical hypothesis testing, experiment design, multivariate analysis, and various methods developed in the field of operational research.
The Project Management Institute refers to the Seven Basic Tools in a Guide to the Project Management Body of Knowledge as an example of a set of general tools useful for planning or controlling the quality of the project.