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Seven basic tools of quality
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<h2 id="overview">Overview</h2> <p>The seven tools are:<a class="footnote-ref" id="fnref:3" href="#fn:3"><sup>3</sup></a><a class="footnote-ref" id="fnref:4" href="#fn:4"><sup>4</sup></a><a class="footnote-ref" id="fnref:5" href="#fn:5"><sup>5</sup></a> </p> <ol><li><a href="/facts/Ishikawa_diagram/vHFlT4dk">Cause-and-effect</a> diagram (also known as the "fishbone diagram" or Ishikawa diagram)</li> <li><a href="/facts/Check_sheet/tdWWzdAC">Check sheet</a></li> <li><a href="/facts/Control_chart/mY27mrUe">Control chart</a></li> <li><a href="/facts/Histogram/oMmvqGEA">Histogram</a></li> <li><a href="/facts/Pareto_chart/FaEn4rx7">Pareto chart</a></li> <li><a href="/facts/Scatter_plot/n03xBtBL">Scatter diagram</a></li> <li><a href="/facts/Stratified_sampling/CvAUCegT">Stratification</a> (alternatively, <a href="/facts/Flow_chart/BtNXBfUG">flow chart</a> or <a href="/facts/Run_chart/mbxLfenr">run chart</a>)</li></ol> <p>The designation arose in <a href="/facts/Postwar_Japan/Dpru0lDy">postwar Japan</a>, inspired by the <a href="/facts/Benkei/IVvFPLTh">seven famous weapons</a> of <a href="/facts/Benkei/IVvFPLTh">Benkei</a>.<a class="footnote-ref" id="fnref:6" href="#fn:6"><sup>6</sup></a> It was possibly introduced by <a href="/facts/Kaoru_Ishikawa/qUH7G3If">Kaoru Ishikawa</a> who in turn was influenced by a series of lectures <a href="/facts/W._Edwards_Deming/ytaxg6sv">W. Edwards Deming</a> had given to Japanese engineers and scientists in 1950.<a class="footnote-ref" id="fnref:7" href="#fn:7"><sup>7</sup></a> At that time, companies that had set about training their workforces in <a href="/facts/Quality_control/lnXbvqvp">statistical quality control</a> found that the complexity of the subject intimidated most of their workers and scaled back training to focus primarily on simpler methods which suffice for most quality-related issues.<a class="footnote-ref" id="fnref:8" href="#fn:8"><sup>8</sup></a> The <a href="/facts/Project_Management_Institute/8AygTItl">Project Management Institute</a> references the seven basic tools in <i><a href="/facts/A_Guide_to_the_Project_Management_Body_of_Knowledge/wrQFzzBh">A Guide to the Project Management Body of Knowledge</a></i> as an example of a set of general tools useful for planning or controlling project quality.<a class="footnote-ref" id="fnref:9" href="#fn:9"><sup>9</sup></a> </p><p>The seven basic tools stand in contrast to more advanced statistical methods such as <a href="/facts/Survey_sampling/wocqQgV7">survey sampling</a>, <a href="/facts/Acceptance_sampling/DID8JcyG">acceptance sampling</a>, <a href="/facts/Statistical_hypothesis_testing/yv9RPF6U">statistical hypothesis testing</a>, <a href="/facts/Design_of_experiments/VMrNftbr">design of experiments</a>, <a href="/facts/Multivariate_analysis/tDuNcWrL">multivariate analysis</a>, and various methods developed in the field of <a href="/facts/Operations_research/H5yJkV5n">operations research</a>.<a class="footnote-ref" id="fnref:10" href="#fn:10"><sup>10</sup></a> </p> <h3>Footnotes</h3> <h3>Bibliography</h3> <ul><li>Duffy, Grace L.; Furterer, Sandra L. (8 June 2020). "Chapter 9. Improvement Tools". <i>The ASQ Certified Quality Improvement Associate Handbook</i>. Quality Press. <a href="/facts/ISBN_(identifier)/15AdSPa9">ISBN</a> 978-1-951058-13-5.</li> <li><a href="/facts/Masaaki_Imai/ekHEd47G">Imai, Masaaki</a> (1986). <a href="https://archive.org/details/kaizenkyzenkey00imai"><i>Kaizen (Ky'zen): The Key to Japan's Competitive Success</i></a> (1st ed.). New York: Random House. <a href="/facts/ISBN_(identifier)/15AdSPa9">ISBN</a> 978-0-394-55186-9.</li> <li><a href="/facts/Kaoru_Ishikawa/qUH7G3If">Ishikawa, Kaoru</a> (1985). <a href="https://archive.org/details/whatistotalquali00ishi"><i>What Is Total Quality Control? The Japanese Way</i></a>. Translated by Lu, David J. (1st ed.). Englewood Cliffs, New Jersey: Prentice-Hall. <a href="/facts/ISBN_(identifier)/15AdSPa9">ISBN</a> 978-0-13-952433-2.</li> <li><a href="/facts/Kaoru_Ishikawa/qUH7G3If"> ——— </a> (1990). <i>Introduction to Quality Control</i> (1st ed.). Tokyo: 3A Corp. <a href="/facts/ISBN_(identifier)/15AdSPa9">ISBN</a> 978-4-906224-61-6.</li> <li>Montgomery, Douglas (2005). <i>Introduction to Statistical Quality Control</i>. Hoboken, New Jersey: John Wiley & Sons. <a href="/facts/ISBN_(identifier)/15AdSPa9">ISBN</a> 978-0-471-65631-9.</li> <li><a href="/facts/Project_Management_Institute/8AygTItl">Project Management Institute</a> (2013). <i>A Guide to the Project Management Body of Knowledge</i> (5th ed.). Newtown Square, Pennsylvania: Project Management Institute. <a href="/facts/ISBN_(identifier)/15AdSPa9">ISBN</a> 978-1-935589-67-9.</li> <li>Tague, Nancy R. (2005). <a href="https://archive.org/details/projectmanagersc0000benz"><i>The Quality Toolbox</i></a> (2nd ed.). Milwaukee, Wisconsin: ASQ Quality Press. <a href="/facts/ISBN_(identifier)/15AdSPa9">ISBN</a> 978-1-62198-045-2.</li></ul> <h2 id="references">References</h2> <ol> <li id="fn:1"><p>Montgomery 2005, p. 148. - Montgomery, Douglas (2005). Introduction to Statistical Quality Control. Hoboken, New Jersey: John Wiley & Sons. ISBN 978-0-471-65631-9. <a href="#fnref:1" class="footnote-back-ref">↩</a></p></li> <li id="fn:2"><p>Ishikawa 1985, p. 198: "From my past experience as much as ninety percent of all problems within a company can be solved by means of these tools." - Ishikawa, Kaoru (1985). What Is Total Quality Control? The Japanese Way. Translated by Lu, David J. (1st ed.). Englewood Cliffs, New Jersey: Prentice-Hall. ISBN 978-0-13-952433-2. <a href="https://archive.org/details/whatistotalquali00ishi" target="_blank">https://archive.org/details/whatistotalquali00ishi</a> <a href="#fnref:2" class="footnote-back-ref">↩</a></p></li> <li id="fn:3"><p>Tague 2005, p. 15. - Tague, Nancy R. (2005). The Quality Toolbox (2nd ed.). Milwaukee, Wisconsin: ASQ Quality Press. ISBN 978-1-62198-045-2. <a href="https://archive.org/details/projectmanagersc0000benz" target="_blank">https://archive.org/details/projectmanagersc0000benz</a> <a href="#fnref:3" class="footnote-back-ref">↩</a></p></li> <li id="fn:4"><p>Ishikawa 1985, p. 198: "Elementary Statistical Method (the so-called Seven Tools) 1. Pareto chart: The principle of vital few; trivial many 2. Cause and effect diagram (This is not precisely a statistical technique) 3. Stratification 4. Check sheet 5. Histogram. 6. Scatter diagram (analysis of correlation through determination of median; in some instances, use of binomial probability paper) 7. Graph and control chart (Shewhart control chart)". - Ishikawa, Kaoru (1985). What Is Total Quality Control? The Japanese Way. Translated by Lu, David J. (1st ed.). Englewood Cliffs, New Jersey: Prentice-Hall. ISBN 978-0-13-952433-2. <a href="https://archive.org/details/whatistotalquali00ishi" target="_blank">https://archive.org/details/whatistotalquali00ishi</a> <a href="#fnref:4" class="footnote-back-ref">↩</a></p></li> <li id="fn:5"><p>Imai 1986, pp. 239–240: "The seven statistical tools used for such analytical problem-solving are: 1. Pareto diagrams ... 2. Cause-and-effect diagrams ... 3. Histograms ... 4. Control charts ... 5. Scatter diagrams ... 6. Graphs ... 7. Checksheets." - Imai, Masaaki (1986). Kaizen (Ky'zen): The Key to Japan's Competitive Success (1st ed.). New York: Random House. ISBN 978-0-394-55186-9. <a href="https://archive.org/details/kaizenkyzenkey00imai" target="_blank">https://archive.org/details/kaizenkyzenkey00imai</a> <a href="#fnref:5" class="footnote-back-ref">↩</a></p></li> <li id="fn:6"><p>Ishikawa 1990, p. 98: "They were named the Seven QC Tools after the famous seven weapons of the Japanese Kamakura-era warrior-priest Benkei which enabled Benkei to triumph in battle; so too, the Seven QC Tools, if used skillfully, will enable 95% of workplace problems to be solved. In other words, intermediate and advanced statistical tools are needed in about only 5% of cases." - ——— (1990). Introduction to Quality Control (1st ed.). Tokyo: 3A Corp. ISBN 978-4-906224-61-6. <a href="#fnref:6" class="footnote-back-ref">↩</a></p></li> <li id="fn:7"><p>Moore, Matthew (30 November 2007). "The Seven Basic Tools of Quality". Improvementandinnovation.com. London. Archived from the original on 19 October 2012. Retrieved 18 May 2013. <a href="https://web.archive.org/web/20121019014101/http://www.improvementandinnovation.com/features/article/seven-basic-tools-quality/" target="_blank">https://web.archive.org/web/20121019014101/http://www.improvementandinnovation.com/features/article/seven-basic-tools-quality/</a> <a href="#fnref:7" class="footnote-back-ref">↩</a></p></li> <li id="fn:8"><p>Ishikawa 1985, p. 18: "It is true that statistical methods are effective, but we overemphasized their importance. As a result, people either feared or disliked quality control as something very difficult. We overeducated people by giving them sophisticated methods where, at that stage, simple methods would have sufficed." - Ishikawa, Kaoru (1985). What Is Total Quality Control? The Japanese Way. Translated by Lu, David J. (1st ed.). Englewood Cliffs, New Jersey: Prentice-Hall. ISBN 978-0-13-952433-2. <a href="https://archive.org/details/whatistotalquali00ishi" target="_blank">https://archive.org/details/whatistotalquali00ishi</a> <a href="#fnref:8" class="footnote-back-ref">↩</a></p></li> <li id="fn:9"><p>Project Management Institute 2013, pp. 236–238. - Project Management Institute (2013). A Guide to the Project Management Body of Knowledge (5th ed.). Newtown Square, Pennsylvania: Project Management Institute. ISBN 978-1-935589-67-9. <a href="#fnref:9" class="footnote-back-ref">↩</a></p></li> <li id="fn:10"><p>Ishikawa 1985, pp. 198–199: "I divide statistical methods into the following three categories according to their level of difficulty. 1. Elementary Statistical Method (the so-called Seven Tools) ... 2. Intermediate Statistical Method ... 3. Advanced Statistical Method (using computers concurrently)". - Ishikawa, Kaoru (1985). What Is Total Quality Control? The Japanese Way. Translated by Lu, David J. (1st ed.). Englewood Cliffs, New Jersey: Prentice-Hall. ISBN 978-0-13-952433-2. <a href="https://archive.org/details/whatistotalquali00ishi" target="_blank">https://archive.org/details/whatistotalquali00ishi</a> <a href="#fnref:10" class="footnote-back-ref">↩</a></p></li> </ol>