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A Guide to Implementing the Theory of Constraints
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Caring About Healthcare “Here is Edward Bear,
coming downstairs now, bump, bump, bump, on the back of his head. It is, as far as he knows, the only way of
coming downstairs, but sometimes he feels that there really is another way,
if only he could stop bumping for a moment and think of it. And then he feels that perhaps there
isn't.” ‑‑ A. A. Milne. How
many Edward Bears are there here I wonder?
How many people, like Edward Bear, are dissatisfied with the current
situation, wonder if there can’t be something better, and then doubt that
there is? Probably quite a few I
suspect. Well, the following pages
were written with the Edward Bears of healthcare in mind. However, for these pages to be of any
benefit, we will have to stop bumping the back of our head for more than just
a moment – there is quite a bit to think about; things that we might not have
thought about before. If you
have just “landed” on this page as the consequence of some frustrated
internet search on healthcare and improvement and Lean, or some other such
facet, then don’t push the “back button” yet.
Hold on for a moment and I will provide some rationale. You may
feel uneasy seeing headings above such as “production” and “supply chain” and
“projects,” as this indicates some operational bias to this website. But this is exactly as it should be; most
of the problems in healthcare are operational. Most of the problems in any modern
enterprise of more than one department are operational. Why is this? Well, operations are full of people, and
with that there are a few challenges that we need to learn to overcome. We are going to do that by invoking a
management philosophy known as Theory of Constraints. If you suffer from improvement fad fatigue,
then you have my sympathy (which is of no use to you), and you also have my
understanding. We are going to look at
why several of the current and past fads have failed to yield the necessary
results and also look at the hugely valuable and more fundamental aspects
that do yield results. Outside of the
Toyota Production System, Theory of Constraints is the only consistent and
fundamental approach to process improvement. I am
going to make an assumption that many people in healthcare are very busy –
after all everyone else is, so I doubt that healthcare is much different, and
maybe it is somewhat worse. Therefore,
this page will not only serve as an introduction but also as a directory to
other parts of the website where there is material that you may need to
follow up. As we learn to bump our
heads less often, we will find that we have more time. People
who have visited this website before will know that I have left healthcare
until after production, supply chain, and projects – the three major
logistical arms that Theory of Constraints applies to. However, my interest in healthcare predates
all of these. It was my interest in
service operations that sent me in search of better approaches to the very
real chaos that prevails throughout professional consultancies. After all, if seemingly clever
professionals such as engineers and scientists are in this state – and a
rather permanent state at that – what then of other forms of business? Were we missing something? Could we learn? And I rather picked that of all the service
operations, surely modern healthcare services must be the most complex of the
lot, surely anything “new” must stand or fall in this environment – hence
part of the attraction. I’ve since
learnt that nothing is too complex, but most things are simply made way too
complicated, complicated beyond belief.
The world is not a complicated place, but we certainly force it to
behave in a very complicated manner. Much of
the problem in modern healthcare – like so much else in the modern world –
has to do with the dynamics of our organizations, not the detail, after all
we are all expert in the day-to-day detail of our profession or area or what
have you. In fact, from the start we
have used two terms here from systems thinking; “dynamic complexity,” and
“detail complexity.” Somewhere along
the way we have asserted that; “dynamic complexity isn’t.” And indeed dynamic complexity isn’t complex
at all. It is our psychology and our
failure to understand what has gone on in the past 100 years that is the
cause of our current situation and the source of the apparent complexity. So,
take a step back for a moment and think.
Think how little removed we are from the discovery of modern
antibiotics, how little removed we are from anesthetic via a chloroform mask,
indeed how little removed we are from formerly complicated surgery such as
appendectomy that used to require an incision that seemed to extend from the
pelvis to the arm. All of
this, of course, is detail complexity.
There is so much we can do today that was unimaginable 10 or 20 or 30
years ago. Relative expectations right
around the world are also so much greater as a consequence. But this is true of any aspect of human
endeavor. People are unlikely to forgo
their Ipods for 78’s (a 78 was a flat plastic disk with music recorded as
analogue grooves that could be played back using a needle – strange but
true), so too with healthcare. What is
missing is an effective approach to dynamic complexity. Think
back again for a minute. Think back
again to hospitalization in the time of our parents or our grandparents. Was it different? Of course it was. It was vastly different. It was much simpler. It doesn’t matter what industry you run
this test on, it will be the same. It
was simpler in that there were less dependencies with which to deal with, and
less choice in any case when such a dependency was brought to bear. I guess that we all long for a former
simpler experience that we seem to have lost, but at the same time we don’t
want to forgo the improved detail that we have gained since. However
this isn’t a win-lose situation. It is
win-win, if only we are willing to learn how.
And in order to be willing to learn how, we must be willing to suspend
some of the things that we have learnt in the past and still hold to be
true. There is a fundamental paradox
in that what we have learnt through personal experience is exactly what we
don’t need if we are to successfully operate a modern healthcare system. There’s
that damn word “system” again, it will undoubtedly keep popping up. The peculiarities of the dynamic complexity
systems that we are going to look at is that they are composed of tasks or
steps or stages that are strongly linear, serial, and dependent. Many stages have a specialist staff that
only do one or two particular things (and very well at that). The trouble is that all of “this” has only
happened in the last 100 years or so, barely a couple of generations. We don’t teach people how to manage this
situation because we fail to recognize that it is different. We “know” how to manage each task or step
or stage – or so we think, if they existed in isolation – and we extrapolate
that out to the belief that competent management of the whole system is
simply the sum of the competent management of each and every task along the
way. In
these webpages we have consistently called this the Reductionist/local optima approach. But
there is another approach that we must
use, the Systemic/global optimum
approach. You
see, healthcare from a dynamical point of view is like a chain, and a chain
as we know is only as strong as its weakest link. We must seek out the dynamical weakest link
and strengthen it and protect it, and once strengthened and protected, we
must search for the next, and so forth, in a process of on-going and
continual improvement. It is not just
the detail of healthcare solutions that must improve, it is the dynamics of
the delivery that must improve as well – and we are starting from behind. We’ve
been here before, many times before, since modern hospitalization first
occurred; scratch the surface and many things that we now take for granted
have their origins in Scientific Management from the early 1900’s. At the moment Lean is the lead mechanism
for healthcare process improvement. That
healthcare professionals are receptive to Lean methodologies indicates only
too well the underlying desire to do better with the limited resources that
we currently do have. After all,
everybody wants to do their best – right? But
Lean is an amalgam of a number of previous attempts at system
improvement. These older strands weave
in and out of the current approach, however, one or two important strands
that ought to be in the mix have been dropped out, and one or two that ought
not to be in the mix have been added in.
Let’s address these briefly. Lean is
essentially an explicit Western academic interpretation of a tacit Eastern
industrial reality that we know today as the Toyota Production System. The Toyota Production System isn’t a recent
development, the philosophical roots go back to the late 1880’s within the
Toyoda family, the intent to manufacture cars extends back to 1911, and the
actuality of beginning to build cars dates from the early 1930’s (1). The two
pillars of the system are; §
Just-in-time. §
Autonomation (automation with a human touch). These
come from the silk spinning & weaving origins of the company and the
Toyoda family. Integral within this is
a focus on the absolute minimization of waste. This major thread, the absolute minimization
of waste comes via the contemporaneous work of Frederick Taylor and Frank and
Lillian Gilbreth in North America in the late 1890’s and early 1900’s
(2). Lillian Gilbreth visited Japan on
a number of occasions and Taylor’s work was translated and vigorously
advocated by Japanese nationals at the time.
Not only has the elimination of waste had a pedigree extending back to
North American industrialization in the 1900’s, it has also reappeared under
the auspices of; Kaizen, Total Quality Management, and World Class
Manufacturing – each of these being an attempt to describe key Japanese
industrial expertise. As I said, we
have been here many times before. A
strand that has been left out of the Lean mix is the impact that W. Edwards
Deming’s methods had on Toyota from 1960 onwards, and many other major
Japanese industries since 1950.
Deming’s work is based upon the foundations established by Walter
Shewhart at Bell Labs in the mid-1920’s (3).
These days the work of Deming is pretty much bastardized under the
banner of Six Sigma and we are all the poorer for it. And this is why people have to talk about
Lean and Six Sigma as a pair within the same breath and within the
same sentence. These
three approaches; the Toyoda’s, Taylor, and Deming/Shewhart were concomitant
with the development of modern industrialization and the needs that arose out
of that. By the mid-1920’s we had the
essentials of what we require except for one thing – an understanding that we
have only had since the mid-1980’s. We
will come back to that soon enough. Another
strand that is left out of the Lean mix is the logistical backbone of
Just-In-Time, either the use of Kanban logistics or Tact time. The reason for this is two-fold. Firstly Kanban and Tact time really are
best suited for repetitive manufacturing.
There are nevertheless places in healthcare where they could be used –
drug and consumable resupply for instance – but generally they are not. This is because of the second reason, the
West’s predilection for data (detail complexity) and computer information
systems, especially those known as material resource planning (MRP II) or
enterprise resource planning (ERP). It
seems to be poorly understood is that Kanban logistics has the essential
function of stopping the waste of over-production. More
critically, Kanban is the focusing
mechanism or driver for process improvement within the Toyota Production
System. A common enough analogy is a
boat floating over hidden rocks. The
rocks (our problems) are hidden in a sea of work-in-process. In healthcare we call these queues, and
they contain people called patients.
The Kanban system functions by reducing the sea of work-in-process
step-by-step until it uncovers a new problem.
The new problem is then addressed using various techniques and
improvements are made until there is no longer a problem. The cycle then continues. Without a focusing system for the whole
process we are left with only local
initiatives, and that unfortunately is how Lean in healthcare functions
at the present. What
then of the threads that have been added to Lean that ought not to have
been? Well, the predominant one is
value stream mapping. The Toyota
Production System is recognized as a new sociotechnical system (4); it is
characterized by people who work within the system all of their working
lives, it is characterized by people who move around within the system, 6
months here, 2 years there, learning how the process works. In the West where, to paraphrase Deming, we
don’t have such constancy of purpose, people don’t actual know the entire
stream of their process, and if we bring in consultants, which isn’t such an
unusual occurrence, the matter is made even worse. We
can’t blame our people, after all our whole management system is built around
local efficiency and departmental optimization, and if that wasn’t enough,
our career progression is determined by individual achievement, not group
achievement. That, however, isn’t a
good reason to adopt value stream mapping.
With focus, you can bring
about real improvement in the time that most people are still trying to work
out how to map their value stream. In the
section called “& More ...” we
discussed in some detail; Deming, Taylor, and Toyota – in fact a page for
each. The point of this was to
illustrate how they have each been systematically mis-understood. They have been systematically
mis-understood because we operate under a paradox or a “cloud” whereby our
personal experience as individuals stops us from learning from our everyday
experience in industry. We called this
the fundamental cloud. You can find
two files in the PowerPoint section that address this in
general terms. Lean
and the predecessors such as Kaizen, Total Quality Management, and World
Class Manufacturing will not help us because they are bereft of context. And the context must be systemic. The original work of Deming, Taylor, and
Toyota had the context embedded within it.
Descriptions of the derivatives lack this aspect. They are, as Taylor described it in 1911,
mechanisms without the essence. You
can see the problem isn’t a new one. Well,
it is a both a curious and fortunate thing that healthcare professionals are
actually exposed to this context, the essence, within their professional
lives. Healthcare professionals do
understand systems – albeit a plethora of sub-systems – in the form of the
human body. And each of these systems
has some rate limiting factor, a weakest link. So too with our healthcare processes. Indeed the healthcare process is best
viewed as a patient. Lets
take a look. Healthcare
professionals know about rate limiting steps.
Rate limiting steps are of course a dynamic entity, however, we are
going to take a step back for a moment and use a simple static analogy – a
chain. Everyone
knows that;
What
about this chain then?
We must
replace this with a different paradigm;
But
let’s now change our analogy; change it away from a physical chain to one of
a “group of groups” of people. Let’s
have a look. Firstly,
here is a group of people.
And
here we have a group of groups of people.
Let’s
have a look at the basic components of the process.
Let’s
look at this another way. Jaques and
Cason define work as; “the exercise of judgment and discretion in making the
decisions necessary to solve and overcome the problems that arise in the
course of carrying out tasks (5).”
This is a non-trivial definition.
If we no longer need to exercise judgment and discretion we can
mechanize or computerize things and maybe automate them as well. This is where Ohno’s “autonomation” comes
in – and remember Ohno’s initial context was automated silk spinning and
weaving, way before any form of electronic control – machines replace the
judgment and discretion that was once the exclusive domain of people. And why would we want to maintain such
exclusivity if we can off-load it for more humanistically rewarding endeavors? So ask
yourself; is the exercise of judgment and discretion a feature of
healthcare? That’s a rhetorical
question, isn’t it? Of course the
exercise of judgment and discretion is a feature of healthcare. That is why our health specialists train
for so long, and in fact never stop learning.
Therefore, we should expect some variability. And don’t forget the patients – they aren’t
exactly uniform either. The potential
mix of any one single patient’s “complicating factors” means variability is
rife within this process. If
variability is rife, then it is only natural that we should attempt to reduce
it, and hence the attraction of the various methodologies that we have
mentioned. If we can locally reduce
variability we ought to expect a better local outcome. Let’s show this.
Well,
the results across the world says no, the total output does not improve. We have buried money into this system in
the last decade and the productivity has been static, people have to be more
ill to be seen, and they wait longer and longer to be seen. Why, why, why, is this? Let’s
have a look.
It’s
sad that since at least 1911 we have known that; “In the past man has been
first; in the future the system must be first (6).” But we still don’t understand what this
means. We blame “the system,” even
though we are part of it, because we don’t understand it; and we don’t
understand it in two mutually exclusive directions; §
Vertical hierarchy – the requisite number of layers
and necessary competence. §
Horizontal process – the existence of serial
dependency and variability. And it
is within the horizontal process that is the second part of the issue with
systems lies. Let’s
have a look.
The two
earlier logistical systems, Ford’s process chain, and Toyota’s Kanban system
implicitly acknowledge the existence of a rate limiting step. Ford uses mechanical linkages and Toyota
uses cards to communicate, across the system, the speed of the rate limiting
step – these systems can’t operate faster than the rate limiting step and all
other parts can not over-produce relative to the rate limiting step. Theory of Constraints continues in this
fashion using time as a logistical “rope.”
It is also the first to explicitly recognize the role of the
constraint. This is the one thing that
has been missing since the 1920’s; explicit recognition of the
constraint – the rate limiting step. Deming
was so very close to this understanding when he described the obligation of a
component to the whole (7). And yes I
know I said there were no parts, but our language lacks the words to describe
this. Let’s
draw the understanding as described by Deming.
Rather
we must have this;
It may
seem counterintuitive, but the discipline for good subordination is far more
important than the discipline for exploitation. We know how to exploit, we try to do it
everywhere all of the time (just trying to doing our best), we need to focus
instead on just the one place where exploitation needs to be done in order to
improve the system as a whole, and subordinate everything else. We need
a systematic and systemic focusing process in healthcare to find and identify
the places to exploit and the places to subordinate if we are to replace
local improvements in outcomes with system-wide improvements in output. Let’s have look at such a process. Taylor,
Deming, and Toyota all have a systemic context embedded within their
methodologies, but none of these previous approaches explicitly recognizes
the role of rate limiting step in the process. Theory of Constraints does. Moreover, it recognizes time rather than
materials as the fundamental measure.
By doing so, a series of similar logistical solutions have been
implemented that bring about rapid, significant, and sustained improvement to
industrialized processes; manufacturing of all types, supply chain, and
projects. The same principles can be
applied directly to healthcare with the same results, and have been for more
than a decade (8). Knowing
what you now know, would you choose to improve a step that is not rate
limiting? You might if there is a
significant deficiency in the current outcome at that step – a medical or
technical or quality issue. But would
that improve the output of the whole chain?
Unfortunately not. This is why,
cost of personnel excluded, so much money is expended upon healthcare for so
little improvement in output. What we
have lacked is focus, and the logistical solutions to go with it. However, both do exist. Let’s look at focus first. Goldratt
proposed a focusing process as follows (9); (1)
Identify the system’s constraints. (2)
Decide how to
Exploit the
system’s constraints. (3)
Subordinate everything
else to the above decisions. (4)
Elevate the system’s constraints. (5)
If in the
previous steps a constraint has been broken, Go back to step 1, but do not allow inertia to cause a system constraint. The
background to this is discussed in detail on the page called Process
of Change, the central importance of time is discussed in
detail on a page called Evaluating
Change, and nature of subordination is discussed on a page called Paradigms in the Strategy
section. If there is a “mantra” in
Theory of Constraints, then the above focusing process is it. Failure to use it, will mean failure to
succeed. However,
there is one caveat, you don’t have
to go through the sequence; identify, exploit, subordinate, elevate, every
time. Some constraints can be broken
at exploitation and you short-circuit the loop and start again. The various “loops” are discussed in a
subpage off the Evaluating Change page called 5 Step Method and also on the Strategy page where you
can be so bold as to proactively select a constraint rather than reactively
identify one. But these are all things
that have to be learnt – and this takes time, there is skill involved. The one
thing that we want to avoid, however, is that almost all non-systemic
improvement methodologies start at the start by identifying a constraint and
then jump directly to the 4th step
and try to elevate the constraint by adding more of it; that is increasing
production rather than increasing productivity. This always involves increased expenditure
of some sort. We will never ever learn
if continue to do that. We are
much “tighter” than that. We expect to
ensure that we are getting the fullest potential out of our existing
constraint first, and that all of the other steps have fallen into line with
this and are protecting the constraint so that we don’t waste any of its
valuable capacity. That is a hugely
different mind-set at first for many people.
Believe me. The
exploitation and subordination tactics come from the work of Taylor,
Ohno/Shigeo, Deming, and a rather special understanding of the buffering of
safety from Goldratt. I urge people to
acquaint themselves with original work on Toyota, and the original work of
Deming. A health service is also a
rather special sociotechnical system but it doesn’t seem to know it. Having
a focusing mechanism with which to direct our toolsets is necessary, but this
of itself is not sufficient. We need
to articulate the broader context.
This is what I mean, we need to; (1)
Define the system. (2)
Define the goal of the system. (3)
Define the necessary conditions. (4)
Define the fundamental measurements. (5)
Define the role
of the constraints. (6)
Define the role
of the non-constraints. We were
introduced to these concepts on the page on Measurements. A more healthcare specific approach was
presented on the page for Replenishment and Healthcare in the Supply Chain
section. There must be a strategic
intent if are to know how to apply our new found tactics. We
summarized this on the page for Paradigms as follows;
This
shows the relationship between the focusing process, our plan of attack, and
the broader context of the environment, our rules of engagement. These are well discussed throughout the
website. Essentially
we must replace the former reductionist/local optima approach of
our pre-industrial psychology with the systemic/global
optimum approach of our industrial reality. We must move past a fixation with detail complexity and recognize that dynamic complexity is an equally
valid component. Slowly we will learn
that most dynamic complexity is really quite simple – if only we would stop
to listen and to learn. We know
enough now to continue with some specifics of healthcare. Let’s summarize and get on with it. In
order to improve healthcare we must approach it in a systemic manner. We must understand the overall context and
then begin to look for the constraints that stop us from improving our
output. Currently we are approaching
the problem without the rigor of a focusing process, we are applying
improvement methodologies with the very best of intent, but without
focus. Indeed some of the improvement
methodologies are derivatives of more systemic approaches, but we need to
return to the fundamentals of the systemic approaches of Taylor, Toyota, and
Deming if we are to avoid another crash and burn. It is
possible to implement rapid, significant, and sustainable improvement in this
environment – healthcare. It is being
done so right now. The knowledge and
skills that have been developed in other environments are portable to this
one. Sure there are some singular
challenges in healthcare, but nothing that can’t be overcome. In the end it is about people, we create
the problems ourselves, and we can fix them too. Remember
that Deming said; “The system is such that almost nobody can do his
best. You have to know what to do, then do your best. Sure we need everybody’s best – everybody
working together with a common aim.
And knowing something about how to achieve it. Not just with what seem to be brilliant
ideas, but with a system of improvement (10).” It is
just amazing that more than 20 years after those words were last aired in the
West and more than 60 years after the Japanese listened, we are still feeling
around in the dark. We don’t usually
have a system of improvement. Who are
we kidding? Surely, only ourselves. In the
next 3 pages there are three specific logistical approaches to
healthcare. They cover the beginning,
the middle and the end points of public service hospitalization, that is;
emergency department, non-acute surgical intervention, and medical/surgical
nursing and discharge. They will
require that most people not do their best in most areas most of the time,
and to do their best in probably just one.
Both the outcome and the output will improve as a consequence. If we use our experience developed with
rate limiting processes then we in fact understand this already. Taiichi
Ohno said it all in 1978 (11); “A business organization is like the human
body.” Anyway,
there is lot to learn, let’s get on with it.
(1) Ohno, T., (1978) The Toyota production system:
beyond large-scale production. English
Translation 1988, Productivity Press, 143 pp. (2) Shingo, S., and Robinson, A., (editor) (1990)
Modern Approaches to Manufacturing Improvement: The Shingo System. Productivity Press pp 21-45. (3) Neave, H. R., (1990) The Deming Dimension. SPC Press, pp 22-23. (4) Hurst, D. K., (1995) Crisis and renewal: meeting
the challenge of organizational change.
Harvard Business School Press, pp 120-123. (5) Jaques, E., and Cason, K., (1994) Human
capability: a study of individual potential and its application. Cason Hall & Co., pg 10. (6) Taylor, F. W., (1911) The principles of scientific
management. Dover Publications reprint
(1998), pg iv. (7) Deming, W. E., (1994) The new economics: for
industry, government, education.
Second edition, MIT Press, pp 95-97. (8) Phipps, B., (1999) Hitting the bottleneck. Health Management Magazine, February, pp
16-17. (9) Goldratt, E. M., (1990) What is this thing called Theory of Constraints and how should it be
implemented? North River Press, pp
3-21. (10) Walton, M., (1986) The Deming Management
Method. Perigee, pg 32. (11) Ohno, T., (1978) The Toyota production system:
beyond large-scale production. English
Translation 1988, Productivity Press, pg 45. This Webpage Copyright © 2008-2009
by Dr K. J. Youngman |
