The Deming Cycle
The Deming cycle, or
PDSA cycle, is a continuous quality improvement model consisting of a
logical sequence of four repetitive steps for continuous improvement and
learning: Plan, Do, Study (Check) and Act. The PDCA cycle is also known
as the Deming Cycle, or as the Deming Wheel or as the Continuous
Improvement Spiral. It originated in the 1920s with the eminent
statistics expert Mr. Walter A. Shewhart, who introduced the concept of
PLAN, DO and SEE. The late Total Quality Management (TQM) guru and
renowned statistician
Edwards Deming modified the Shewart cycle as: PLAN, DO, STUDY, and
ACT.
Along with the other
well-known American quality guru-Joseph
Juran,
Edwards Deming went to Japan as part of the occupation forces of the
allies after World War II.
Deming taught a lot of Quality Improvement methods to the Japanese,
including the usage of statistics and the PLAN, DO, STUDY, ACT cycle.
The graphic above shows
Deming's Plan-Do-Check-Act (PDCA) cycle. (Deming himself called it the
'Shewhart Cycle' but Deming's work in Japan has lead to it commonly
being named after him.) In BPE, everything is done with the discipline
of PDCA. At all levels of the organization we:
-
Plan
what we are going to do. In this step we assess where we are, where
we need to be, why this is important, and plan how to close the gap.
Identify some potential solutions.
-
Do
try out or test the solutions (sometimes at a pilot level).
-
Check
to see if the countermeasures you tried out had the effect you hoped
for, and make sure that there are no negative consequences
associated with them. Assess if you have accomplished your
objective.
-
Act
on what you have learned. If you have accomplished your objective,
put controls into place so that the issue never comes back again. If
you have not accomplished your objective, go through the cycle
again, starting with the Plan step.
Frequently, a
particular project will define sub-objectives, run thorough the PDCA
cycle one or more times to accomplish the sub-objective, then define the
next objective and go through the cycle again. Thus, many projects end
up "turning the wheel" many times before completion. In ongoing
management activities, we find a similar use of the cycle.
What we are trying to
avoid by using the PDCA discipline is the "Ready, Fire, Aim" fallacy
where people jump to the solution without identifying the problem and
assessing if their proposed solution fixes it, or even results in
another problem. The Act step makes sure we don't have to fix it again
in a couple of years.
Problems With Deming
Cycle
The Deming Cycle's
application was intended for quality control purposes and proposed
continuous improvement in quality of products/experiments.[4] The simple
cycle works well in this application, but it is debatable that it should
be applied to major organizational improvement. ISO recognized the need
to provide better guidance in this regard and published the ISO standard
ISO 9004:2000, which replaced the use of the term continuous improvement
with continual improvement. The change is not trivial, it recognizes
that organizational quality system performance improvement requires
significant effort and needs pauses to consolidate change (hence
continual and not continuous improvement) (ISO 9004:2000).
The Deming Cycle has an
inherent circular paradigm, it assumes that everything starts with
Planning. Plan has a limited range of meaning. Shewart intended that
experiments and quality control should be planned to deliver results in
accordance with the specifications (see meaning above), which is good
advice. However, Planning was not intended to cover aspects such as
creativity, innovation, invention or Complex Adaptive Systems. In these
aspects particularly when based upon imagination, it is often impossible
or counterproductive to plan (see referenced Wikipedia pages for why
this is so). Hence, PDCA is inapplicable in these situations.
The Deming Cycle
approaches often do not get to the root cause of a problem, especially
in adaptive situations which call for an experiential approach but
demand much more rigour in analysis and data collection. An adaptive
challenge exists where there are no visible solutions to problems, and
can exist, for example in areas where chaos, uncertainty, and ambiguity
exists, such as new frontiers, and existing complex systems such as
Healthcare.
Do and Act have the
same meaning in English. Dictionaries (Shorter Oxford) provide the
following relevant definitions:
-
Do: verb 1 perform
or carry out (an action). 2 achieve or complete (a specified
target). 3 act or progress in a specified way. 4 work on (something)
to bring it to a required state.
-
Act: verb 1 take
action; do something. 2 take effect or have a particular effect. 3
behave in a specified way.
The 'Act' in the Deming
Cycle is meant to be interpreted to have a different meaning to 'Do',
otherwise it could be as easily have been PDCD or PACA. In PDCA, 'Act'
is meant to apply actions to the outcome for necessary improvement (see
meaning above), in other words 'Act' means 'Improve' (applying PDCA to
itself could result in PDCI).
The Deming Cycle is a
set of activities (Plan, Do, Check, Act) designed to drive continuous
improvement. Initially implemented in manufacturing, it has broad
applicability in business. First developed by Walter Shewhart, it is
more commonly called the Deming cycle in Japan where it was popularized
by
Edwards Deming.
Deming Cycle is also
known as Shewhart cycle, PDCA, Plan-Do-Check-Act
References
http://en.wikipedia.org/wiki/PDCA
http://www.balancedscorecard.org/TheDemingCycle/tabid/112/Default.aspx
http://www.valuebasedmanagement.net/methods_demingcycle.html
|
