Systems and Improvement

Dr. W. E. Deming was fond of saying in his seminars, “This diagram was on the wall in Japan.”  Deming, an esteemed statistician who is perhaps best known for his work in Japan, later made systems thinking one of the four parts of what he call the System of Profound Knowledge, profound, he said, because it is important and it is rare.

What we can see here is a process depicted schematically.  It can be any process.   There are suppliers who provide material, methods, people, equipment, and so on.  They are received, sometimes with inspection or test, and entered into the process flow where they are assembled, instructed, interviewed, shaped, welded, or whatever it is the process does.In this central part of the process, they may be inspected or measured on dimension, but often they are not.

 Frequently quality characteristics have not been defined.  With material this can be hardness, shape, dimensions and so on.  With service processes, the quality characteristics might be waiting time, errors, completeness and accuracy of forms or records, processing time, etc.

Then the process results are distributed, perhaps to the customer, but maybe to the next process step or even to one of the people who were an original supplier.  This would be the case, for example, in  an outpatient clinic where an individual brings insurance forms, gets them filled out and is given them back with the appropriate information contained therein. 

Upon distribution some assessment as to adequacy is made.  Did the service or product produced by the process meet the requirements.  Sometimes this assessment is in the form of an elaborate sampling and inspecting procedure.  Sometimes it is a glance at the paperwork by a customer.  

It is important to note that at this point in the process the purpose of the inspection is to assess the quality, not to produce it.  The quality of product or service at this point has already been determined by what happened before.

The results of the assessment are then fed back upstream for improvement, confirmation or whatever the results might indicate.  This is the famous PDSA (Plan Do Study Act) process at work.  Perhaps the results of final assessment are combined with the results of consume research and a process of product, service or process re-design is begun. 

Thus did Deming, over sixty years ago,  show a basic model about how to think about quality and improvement.