Editing Quality assurance (section)

== History ==
=== Initial efforts to control the quality of production ===
During the [[Middle Ages]], [[guild]]s adopted responsibility for the quality of goods and services offered by their members, setting and maintaining certain standards for guild membership.<ref>[http://asq.org/learn-about-quality/history-of-quality/overview/overview.html ASQ – "History of Quality"]. Retrieved 17 November 2014.</ref>

Royal governments purchasing material were interested in [[quality control]] as customers. For this reason, King [[John of England]] appointed William de Wrotham to report about the construction and repair of ships.<ref name="BrooksWilliam25">{{cite journal |title=William de Wrotham and the Office of Keeper of the King's Ports and Galleys |journal=The English Historical Review |author=Brooks, F.W. |volume=40 |issue=160 |pages=570–579 |year=1925 |doi=10.1093/ehr/XL.CLX.570}}</ref> Centuries later, [[Samuel Pepys]], Secretary to the British Admiralty, appointed multiple such overseers to standardize sea rations and naval training.<ref name = "RMGSam">{{cite web |url=http://www.rmg.co.uk/discover/explore/samuel-pepys-and-navy |title=Samuel Pepys and the Navy |publisher=Royal Museums Greenwich |access-date=29 November 2017 |date=2015-08-17 |archive-date=2017-11-29 |archive-url=https://web.archive.org/web/20171129215418/http://www.rmg.co.uk/discover/explore/samuel-pepys-and-navy |url-status=dead }}</ref>

Prior to the extensive [[division of labor]] and [[mechanization]] resulting from the [[Industrial Revolution]], it was possible for workers to control the quality of their own products. The Industrial Revolution led to a system in which large groups of people performing a specialized type of work were grouped together under the supervision of a foreman who was appointed to control the quality of work manufactured.

=== Wartime production ===
During the time of the [[World War I|First World War]], manufacturing processes typically became more complex, with larger numbers of workers being supervised. This period saw the widespread introduction of [[mass production]] and [[piece work]], which created problems as workmen could now earn more money by the production of extra [[product (business)|products]], which in turn occasionally led to poor quality workmanship being passed on to the [[assembly line]]s. Pioneers such as [[Frederick Winslow Taylor]] and [[Henry Ford]] recognized the limitations of the methods being used in mass production at the time and the subsequent varying quality of output. Taylor, utilizing the concept of scientific management, helped separate production tasks into many simple steps (the assembly line) and limited quality control to a few specific individuals, limiting complexity.<ref name="PappQuality14">{{cite book |url=https://books.google.com/books?id=1akTBQAAQBAJ&pg=PA3 |title=Quality Management in the Imaging Sciences |author=Papp, J. |publisher=Elsevier Health Sciences |page=372 |year=2014 |isbn=978-0-323-26199-9}}</ref> Ford emphasized standardization of design and component standards to ensure a standard product was produced, while quality was the responsibility of machine inspectors, "placed in each department to cover all operations ... at frequent intervals, so that no faulty operation shall proceed for any great length of time."<ref name="WoodHenry03">{{cite book |url=https://books.google.com/books?id=3XXxhbDU9P4C&pg=PA300 |title=Henry Ford: Critical Evaluations in Business and Management |editor1=Wood, J.C.|editor2=Wood, M.C. |publisher=Taylor and Francis |volume=1 |page=384 |year=2003 |isbn=978-0-415-24825-9}}</ref>

Out of this also came [[statistical process control]] (SPC), which was pioneered by [[Walter A. Shewhart]] at Bell Laboratories in the early 1920s. Shewhart developed the control chart in 1924 and the concept of a state of statistical control. Statistical control is equivalent to the concept of [[exchangeability]]<ref name="BarlowFound92">{{cite book |author1=Barlow, R.E.|author2=Irony, T.Z. |title=Current issues in statistical inference: Essays in honor of D. Basu |chapter=Foundations of statistical quality control |volume=17 |pages=99–112 |year=1992 |doi=10.1214/lnms/1215458841|series=Institute of Mathematical Statistics Lecture Notes - Monograph Series |isbn=978-0-940600-24-9 |url=http://projecteuclid.org/euclid.lnms/1215458841 }}</ref><ref name="BergmanConcept08">{{cite journal |title=Conceptualistic Pragmatism: A framework for Bayesian analysis? |journal= IIE Transactions|author=Bergman, B. |s2cid= 119485220|volume=41 |issue=1 |pages=86–93 |year=2008 |doi=10.1080/07408170802322713}}</ref> developed by logician [[William Ernest Johnson]], also in 1924, in his book ''Logic, Part III: The Logical Foundations of Science''.<ref name="ZabellPredict92">{{cite journal |title=Predicting the unpredictable |journal=Synthese |author=Zabell, S.L. |s2cid=9416747 |volume=90 |issue=2 |pages=205–232 |year=1992 |doi=10.1007/BF00485351}}</ref> Along with a team at AT&T that included Harold Dodge and Harry Romig, he worked to put [[Sampling (statistics)|sampling]] inspection on a rational statistical basis as well. Shewhart consulted with Colonel Leslie E. Simon in the application of control charts to munitions manufacture at the Army's [[Picatinny Arsenal]] in 1934.<ref name="WPLeslie">{{cite web |url=http://apps.westpointaog.org/Memorials/Article/7292/ |title=Leslie E. Simon 1924 |publisher=West Point Association of Graduates |access-date=29 November 2017 |archive-date=29 November 2017 |archive-url=https://web.archive.org/web/20171129222738/http://apps.westpointaog.org/Memorials/Article/7292/ |url-status=dead }}</ref> That successful application helped convince Army Ordnance to engage AT&T's George Edwards to consult on the use of statistical quality control among its divisions and contractors at the outbreak of World War II.<ref name="LittauerTheDevel50">{{cite journal |title=The Development of Statistical Quality Control in the United States |journal=The American Statistician |author=Littauer, S.B. |volume=4 |issue=5 |pages=14–20 |year=1950 |doi=10.2307/2681449|jstor=2681449 }}</ref>

=== Postwar ===
After World War II, many countries' manufacturing capabilities that had been destroyed during the war were rebuilt. [[General Douglas MacArthur]] oversaw the rebuilding of Japan. He involved two key people in the development of modern quality concepts: [[W. Edwards Deming]] and [[Joseph Juran]]. They and others promoted the collaborative concepts of quality to Japanese business and technical groups, and these groups used these concepts in the redevelopment of the Japanese economy.<ref name="MilakovichImproving95">{{cite book |url=https://books.google.com/books?id=tfcrMHfMKd0C&pg=PA13 |title=Improving Service Quality: Achieving High Performance in the Public and Private Sectors |author=Milakovich, M. |publisher=CRC Press |year=1995 |page=280 |isbn=978-1-884015-45-8}}</ref>

Although there were many people trying to lead United States industries toward a more comprehensive approach to quality, the US continued to apply the Quality Control (QC) concepts of inspection and sampling to remove defective products from production lines, essentially unaware of or ignoring advances in QA for decades.<ref name="ASQTotal">{{cite web |url=http://asq.org/learn-about-quality/history-of-quality/overview/total-quality.html |title=Total Quality |work=Learn About Quality |publisher=American Society for Quality |access-date=29 November 2017}}</ref>