7 quality tools

7 quality tools
See also


7 quality tools were created by quality practitioners over the years and collected in one group in early 50s in Japan. Along with the quality movement they were popularized as quality tools. Development of quality methods and techniques lead to creation of new set of quality tools, which extended the older one.

7 Traditional quality management tools

Traditional tools are called Magnificent seven. They are the most commonly used and they are of fundamental importance. These tools can be used on its own, but often are used as components of quality management methods. They are based on simple mathematics and statistics. Therefore, they are often called statistical process control tools. The tools include:

  • Fish diagram - cause and effects diagram used to find many levels of causes of analysed result
  • Check sheet - helps collecting data about quality in the process
  • Control chart - shows variability in the process and helps to analyse it.
  • Histogram - enables to show on chart the distribution of data. In controlled process it usually looks like Gauss curve (normal distribution)
  • Pareto chart - shows the most important elements of the group according to chosen criteria. It uses the 80-20 rule.
  • Scatter diagram - shows correlation between two variables
  • Flow chart - chart presenting flow of the process.

7 new quality management tools

Along with the development of quality management 7 new tools were created. They were designed to enhance traditional tools. They enable a better information flow in the enterprise. They are very important when solving problems.

They include:

  • Affinity diagram - finding relationships between ideas
  • Relations diagram - diagram showing causal relations between aspects of complex situation
  • Matrix diagram - shows relationships between many variables using many dimensions
  • Matrix data analysis -
  • Arrow diagram - used to show the flow of process or project, similar to CPM method
  • Tree diagram - breaks down categories into subcategories, parts, elements, etc.
  • Process decision programme chart - identifies what may go wrong during realization of the plan.

References