Session C9
#2287
Lean Six Sigma: The Pursuit of a Perfect Emergency Department
Brandon D’Aloiso (bdd31@pitt.edu), Seth Young (say19@pitt.edu)
Abstract— This paper will focus on the use of the Lean
LEAN VS. SIX SIGMA
Six Sigma principles in an emergency room setting. The
current level of efficiency of emergency rooms will be
examined and we will discuss the ways in which Lean Six
Sigma principles can be implemented. Ways to lower
infection rates and still keep wait times down will also be
explored. Six Sigma methodologies are currently used in
industry and are now being applied in hospital settings.
Lean Six Sigma focuses on continuous improvement and
waste reduction practices that can be used to achieve near
perfection or “Six Sigma,” which is defined as six standard
deviations from perfection. The focus of Lean, on the other
hand, is on total elimination of waste, while still respecting
the employees and their jobs by not firing personnel already
in the system.
The current status of emergency rooms is intolerable to
patients and the need for reform practices, such as Lean Six
Sigma, is apparent and growing. By bringing industrial
engineers into the medical scene, hospitals can cut down on
the level of waste tremendously. The goal of this paper will
be to examine the intricate details of an emergency room,
then move on to consider the implementation of a feasible
solution that would ideally eliminate the current level of
waste that could be life threatening.
Lean and Six Sigma are two continuous improvement
methodologies that are being used in conjunction with one
another to lower waste and increase productivity in the
business world. Those in the healthcare system however
have taken notice of the effectiveness of these practices and
have decided to attempt to implement these two systems into
their own organizations. The use of Lean and Six Sigma in
hospital settings is relatively new. Together, Lean and Six
Sigma have been very successful in other settings. A
hospital in New Jersey has been able to reduce the average
time spent in their emergency department waiting for a
doctor from four hours to about 38 minutes[1]. Using Lean
and Six Sigma together has really allowed this hospital to
reduce its waste, boost its productivity and still keep the
whole process as safe, if not safer than it was before.
What exactly are Lean and Six Sigma? Lean is a
methodology pioneered by Taiichi Ohno of Toyota in
1988[2]. Ohno saw the ways in which he could boost his
company’s productivity by eliminating all waste from his
processes. Waste is defined below in greater detail, but for
now we will consider waste to be all those things that do not
contribute to the success of a process[2]. Waste can be
anything from lag time between steps to an overstocked
inventory in which the surplus expires or otherwise cannot
be used[2]. Lean is focused on reducing the amount of
waste present using flow charts and diagrams to allow a
team of highly change-oriented individuals to identify waste
in the process and think of ways in which these processes
can be improved. These solutions to reduce waste can be
anything from a checklist outlining the way to do a job
correctly to a new step-by-step protocol to be used as a new
standard, and even to something as simple as color-coding
bins of supplies[1]. These practices not only allow for better
productivity, but also, by allowing a team of employees to
create these new systems and protocols it ensures that they
will be successful because the employees have a vested
interest in their implementation. Lean is only one half of the
pair however; Six Sigma seems to be an opposing theory but
together they are compatible.
Six Sigma does not focus on the elimination of waste but
instead it focuses on the minimization of defects. Six Sigma
was created by the Motorola Company in 1986[1]. Six
Sigma was developed for similar reasons as Lean and is used
in similar situations. Six Sigma is defined as six standard
deviations from the optimal product or having 3.4 defects
per million production opportunities[3]. Six Sigma seems to
be as near perfection as is possible and is something
companies using the Six Sigma methodologies should strive
Key Words— Continuous Improvement, Emergency
Department, Healthcare, Lean, Six Sigma, Waste
Elimination
LEAN SIX SIGMA: OVERVIEW
On average the wait time in emergency departments is
alarmingly high. On top of that, the number of accidents by
care professionals continues to rise. These issues are not due
to a lack of knowledge or skill by the medical staff, but
rather a faulty process by which they operate. Over recent
years, hospitals, especially emergency departments, have
been taking advantage of the combination of two continuous
improvement processes, Lean and Six Sigma. These
processes both address problematic areas within
organizations. Lean practices focus on the elimination of
waste, while Six Sigma’s goal is to reach six standard
deviations from perfection. Six Sigma does this by reducing
defects, making a process ideally near perfection. The use
of these practices in conjunction with one another has shown
continuous improvement in hospitals. By lowering the
number of defects and by reducing the amount of waste the
two practices have led hospitals to not only achieve higher
efficiency and safety, but also be successful in a more cost
effective manner.
University of Pittsburgh
Swanson School of Engineering
April 14, 2012
1
Brandon D’Aloiso
Seth Young
implementation of Lean practices, to be successful, one must
first identify all the different kinds of waste that are present
in the setting they are looking to improve. If waste cannot
be identified, then how can it be eliminated?
Taiichi Ohno, the inventor of the Toyota Manufacturing
System and creator of Lean Manufacturing, identified seven
different categories of waste that can be applied to any
setting[2]. These broad categories help review the entire
system and see the waste that is present everywhere, not just
in one specific setting. The following are types of waste as
defined by Ohno: defects, overproduction, transportation,
waiting, inventory, motion, and over processing. An eighth
category, human potential, was added later on by other
theorists of Lean.
to reach. Companies hope to attain Six Sigma using the two
processes of DMADV and DMAIC[3]. These processes are
defined in greater detail later in the paper but both focus on
improving the design of existing and brand new systems to
reduce the overall number of defects in a company or
processes’ output. Six Sigma methodologies include
identifying a problem, collecting and analyzing data on it,
finding ways to improve the process and controlling the end
result[1]. The people that carefully follow these steps are on
teams formed of many different levels of Six Sigma
knowledge. The different levels of Six Sigma are outlined by
a Belt Hierarchy similar to Karate Belts; black being the
highest level of knowledge and white being the lowest[1].
Black belts are usually people who hold high positions
within a hospital and white belts are people on staff not
directly involved with the team but still following its
directives. The middle belts, Green and Yellow, are the
actual team members focused on improving the hospital by
following the DMADV and DMAIC metrics[3]. The Green
Belts are usually those put in charge of Six Sigma projects
and the Yellow Belts are usually the staff members (nurses
and doctors) consulted to work at implementing the Green
Belts work[3]. By having a team follow both of these
metrics, DMADV for new processes and DMAIC for
preexisting processes, organizations can ensure a faster,
more efficient, and overall more cost effective process.
These continuous improvements combined with the waste
reduction techniques from Lean can assure that a process is
at its peak performance level. The promising
accomplishments of Lean and Six Sigma together are what
have led to its cross over into the health care sector.
By combining Lean and Six Sigma, hospital executives
can assure that their hospital is top notch. By using these two
processes, hospitals are safer, faster, and more cost effective.
This new level of efficiency must translate all the way down
from the executives to the janitorial staff. The emergency
department (ED) is where this new level of efficiency can
most easily be seen. In the emergency department Lean Six
Sigma can reduce wait times, lower infection rates, and
boost productivity for emergency department staff. Lean
helps ED staff have successful outcomes for patients by
assuring that every moment spent in the ED is not wasted
(time, talent, etc.) and that patients are safer by removing all
waste in the form of time spent having to redo steps
performed incorrectly. By using Lean and Six Sigma,
emergency departments across the country will revolutionize
the process of getting treatment to a level that is much more
acceptable to patients. These two continuous improvement
practices used in conjunction with one another are the best
hope at achieving this goal for modern emergency
departments.
TABLE I
A Summary of the Types of Waste
Defects
Overproduction
Transportation
Waiting
Inventory
Motion
Over Processing
Human Potential
Types of Waste
Mistakes
Overdone Steps
Transport time is Waste
Wait time between Steps
Surplus that Expires
Unnecessary Movements
Doing Non-Valued Work
Doctors and Nurses Idle
Defects
A defect is typically the most recognizable type of waste
because of the real possibility for danger. Especially within
the healthcare realm waste can cause a lot of harm because it
is dealing directly with people’s lives. The basic definition
of a defect is any work related action that is not done
correctly the first time[2]. A situation such as this is not
only problematic, but can also lead to other forms or waste
such as a loss of time while the action is repeated, or the
constant need to check for errors; slowing down the process
versus moving at full speed knowing everyone did their job
correctly. Defects are a common type of waste especially in
emergency departments. A few examples include carts
missing items that were not restocked or the dispensing of
the wrong dosage of medication. It is estimated by the
Institute of Medicine that 400,000 preventable drug-related
injuries occur every year, because of illegible handwriting,
misplaced decimal points, and many other defects within the
processes[2]. It is easy to blame the doctor or nurse in these
situations because most of the time they are human errors.
When studying Lean, however, one must look at the bigger
picture to try and figure out why they made this mistake.
Typically a flaw in the process, rather than human error,
causes most defects and waste.
WASTE IN THE EMERGENCY DEPARTMENT
Lean, by definition, is the total elimination of waste. But
what exactly is waste? When studying and looking at the
2
Brandon D’Aloiso
Seth Young
because employees have multiple responsibilities[2]. Lastly
in the waste of time spent waiting are the employees. This
statement may make it sound like doctors and nurses are not
doing their job, but actually, because of the process defects
or delays in processes further up the system, the employees
are forced to waste time waiting around. Other reasons for
this waste involve their contracts and unevenly distributed
workload among the employees[2]. In the emergency
department, the waste of time by employees usually depends
on the number of patients they must care for; therefore if
only five patients are in the ED then many of the employees
sit around and wait for their services to be called upon. The
amount of employees is necessary waste because at any
moment’s notice a busload of injured victims in critical
condition could come in and the employees must be there to
aid the victims.
Overproduction
Another category of waste is overproduction, which may
sound impossible in an emergency department that is
typically spread thin and always running around to keep up
with the fast pace environment. Overproduction, however,
can also refer to doing more than what is required for a
patient or completing it sooner than needed[2]. This type of
overproduction happens every day in emergency
departments across the country. In many hospitals, a blood
test and tox-screen of every patient through the door is
required. While this protocol is intended to speed up the
process of patient care, in reality it does just the opposite.
Usually only 10% of those pre-screening procedures were
necessary in the diagnosis of the patient, thus requiring
nurses to do unnecessary work, wasting time[2]. Instead
nurses could either wait to draw blood or only draw the
blood from those who will obviously need that blood test.
As far as providing services earlier than needed, another
example of this type of over production is delivering
medications too early. These medications are then sent back
to the pharmacy, wasting the transporters time with extra
trips to and from the pharmacy, and the pharmacist’s time by
forcing them to reprocess the medications that are
returned[2].
Inventory
Another form of waste is excess inventory. Inventory can be
considered waste because money is tied up in stocking the
storage closets. This excess inventory however is just sitting
on shelves and not being used right away. While it can be
argued that this stock is eventually used, it could be explored
using Lean what the optimal inventory to have stocked is.
This process would be delicate would need to be studied
closely because a fluctuation of supplies used on a weekly or
monthly basis. On one side, a hospital cannot have a huge
excess of product that will expire[2]. On the other hand, too
few of a product in such a case would cause costly “run
outs” of a specific supply. A mistake in inventory stocking,
though seemingly small, could end up being devastating to a
patient’s health. The hospital may need to expedite an order
and pay extra[2]. Both of those scenarios involve waste of
profits. Thus managing the right amounts of supplies and
medications in a hospital is extremely important for both
patient care and the bottom line for the hospital.
Transportation
The waste of transportation is common among the
movement of patients and medical supplies in an emergency
department. Since every patient treated is evaluated on a
case-by-case basis, there is little to no way to prepare for
every scenario in each patient’s room. This disorder and
randomness results in frequent runs to the supply closet to
get supplies or trips down the hall to get the only ENT Cart
in the department. In addition, there are also frequent trips
transporting the patient to and from the MRI room to the
Catheterization Lab, etc. This waste of transportation is due
to the poor layout of a hospital, which can be prevented with
the future use of transportation-friendly layouts in design
plans for new hospitals or in renovations[2].
Motion
When managers see their employees constantly running
around to get the job done, the managers equate activity with
a hard worker. In reality, it may be that the employees must
include all of this extra motion simply to do their job,
wasting motion. This type of waste is the unnecessary
movement by employees in the system. Waste like this is
severe for nurses in the Emergency Department. In fact, it is
estimated that nurses walk an average of 3.5-4.5 miles per
twelve hour shift[2]. This leads to fatigue of the nurses’
physical and mental health which could lead to defects in
their work[2]. If hospitals were to implement Lean practices
by restructuring their layout of a department and move
commonly used equipment and supplies to a more central
and convenient location it would cut down on wasted of
motion. This organization would also increase the time
employees have to complete their other value added tasks.
Waiting
Probably the most recognizable type of waste, and the one
that causes the most frustration for patients, is the waste of
time spent waiting for care. This category can be broken up
into smaller components based upon who or what is waiting
around. Patients spend time waiting for the nurse to admit
them to a room in the emergency department, sometimes for
several hours. They then must wait for the doctor to see
them and diagnose their problem. Finally, after that, they
must wait to be released by the nurse and discharged[2].
This allows for much improvement by Lean practices.
Products can also be stuck waiting around. A few examples
include tubes of blood waiting to be tested, instruments
needing sterilized, and pharmacy orders that wait on a cart
3
Brandon D’Aloiso
Seth Young
employees to organize the improvement efforts throughout
the organization[4].
When referring to the Six Sigma methodologies, one
must first distinguish between the applications of the
process. There are two methodologies, both of which are
identical for several steps but differ slightly depending on
whether the system to which it is being applied is already
established and looking to improve upon their process, or if
one is starting a new process from nothing. The processes
for an established setting are: define, measure, analysis,
improve, control. (DMAIC) The phases for a newly
established process are: define, measure, analysis, design,
verify. (DMADV) In both cases the first three phases are
identical, with a slight difference in the last two phases.
The first phase of either process is the define phase. The
initial process goal is to hone in everyone’s attention on the
problem and define the optimal goal at the end of the
project. One way of going about this is to write a project
charter which defines the step by step process as well as
boundaries of this project. Also, within the charter includes
the possible outcomes and opportunities of the process, as
well as risks, and SIPOC diagrams (suppliers, inputs,
processes, outputs, customers) which are also drawn up by
the team to pinpoint the elements of the process[4].
The measure phase is the next step in the Six Sigma
process. The primary goal is the collection of data and
information. Once the data is collected, the team must set
the target number that they wish to reach in order for the
process to be considered a success. From there on out, data
will be collected on a regular basis and will be compared to
the reference data that was initially collected[3]. The main
use of this data is to determine the fundamental causes of the
problems in the system.
In the analyze phase, team members carefully study the
data with different Six Sigma tools that provide definitive
statistics about the areas that need improvement. This step
specifically requires the knowledge of current employees
within the system that can determine the cause for
inefficiency[3]. Then the team brainstorm ideas to improve
upon that flaw that would hopefully yield more concise
statistical data.
Over Processing
The waste of over processing, defined by Graban, is doing
work that is not valued by the customer, or caused by
definitions of quality that are not aligned with patient
needs[2]. Basically, it is doing something to a higher level
of quality than what the patient expects or requires from an
employee. In a healthcare setting, one possible example
would be some of the information filled out on forms by
nurses that is never used as data or for anything else[2].
These unnecessary forms and information take crucial time
out of a nurse’s rounds while she could be taking care of
patients. Instead of doing value added tasks she is doing
non-value added tasks.
Human Potential
The waste of talent, the category added later to the initial
seven categories of waste defined by Ohno, is a waste of
employee ideas. Some still do not recognize this as a
practice of Lean, but it could turn out to be the biggest waste
of any. Human potential is amazingly large. Human beings
are capable of doing more than they realize they can do and
have the ability to think for themselves to identify their own
waste. Many managers tend to try and suppress their
employees’ ideas in fear of losing control, but this will cause
employees to resent their boss and lose their desire to work
hard and be creative thinkers[2]. As much as Industrial
Engineers can be extremely helpful in healthcare settings,
they do not know all of the ins and outs of a process like the
employees do. Since the nurses deal with the process in the
Emergency Department on a daily basis, they too should be
listened to in productivity and Lean meetings.
Identifying the waste in any system is crucial for Lean
practices to be successful. It is impossible to fix a problem
without knowing exactly what to fix. These eight types of
waste help to specify all of the different wastes in a
situation, especially an Emergency Department.
STEPS TO ACHIEVING SIX SIGMA: D.M.A.I.C.
AND D.M.A.D.V.
While Lean is all about the removal of Waste and NonValue Added Tasks, Six Sigma is about reducing Defets
caused by this waste. When one studies Six Sigma in depth,
they realize the necessity of sticking to the strict
methodology when going about implementing the process in
a desired system. Six Sigma methodologies are a structured
and rigorous approach to improving the efficiency of a
process by eliminating the sources of variation. If one does
not follow the methodologies, the Six Sigma process has a
great chance of failure due to a weak study of processes with
inappropriate tools for collecting and analyzing data, as
observed by Vest and Gamm in 2009. Chakravorty
considered the cause of the failed Six Sigma process to be
due to a lack of implementation models to guide the
Figure 1
DMAIC and DMADV in Summary[5]
4
Brandon D’Aloiso
Seth Young
of DMADV and DMAIC (outlined above) to identify places
to reduce waste and also create new protocols that cut down
on errors.
The creation of these protocols, however, will never be
enough. At first, high goals must be set that seem near
impossible. The employees should be constantly reminded
of these goals and of the hospitals progress towards these
goals. By effectively showing nurses and doctors that Lean
Six Sigma really is doing what they never thought possible,
there will be a higher adoption and acceptance rate among
all hospital employees. Another important way to ensure that
employees stick to the newly designed protocols is to have
some sort of employee recognition program. By allowing
patients and other employees[1] to recognize doctors, nurses,
and other hospital staff in some sort of system that really
does reward employees at some set rate, employees are
encouraged to take better care of the patients.
A final way that hospitals can ensure the implementation
and retention of Lean Six Sigma methodologies is to
advertise them all over the hospital. Granted, most of the
finer details should be left out, but by making posters that
encourage patients to ask caregivers to wash their hands, ask
about their care, et cetera, the leaders of the Lean Six Sigma
initiative can have their own “police force” in the patients.
Also, by having a mantra or saying such as: “Reduce Delay
by: Delivering the RIGHT care, at the RIGHT time, to the
RIGHT patient,”[6] the Lean Six Sigma methodologies are
something that doctors and caregivers can never get out of
their minds.
Lean Six Sigma has the potential to revolutionize
healthcare and specifically the Emergency Department. By
overcoming these basic obstacles and any others that might
crop up along the way, emergency departments can
drastically reduce wait times, boost patient satisfaction, and
ultimately increase profit margins making a trip to the
emergency room something that is a little easier for patients
and friendlier to a hospitals accounting department.
The fourth phase depends on the process. In the DMAIC
process, the improve phase takes the suggested ideas in the
previous phase and implements them into the process. This
involves the black belt to inform the employees of the
changes and to oversee that the transition runs smoothly[3].
Similarly in the final phase of DMAIC, the black belt
continues to monitor the process in the control phase and
sustain the gains. His or her job is to manage and take
control of any obstacles that arise with the sudden
change[3].
When looking at the DMADV process, the fourth step is
the design phase.
This phase is to design new
methodologies that will enhance the original process. Also,
it prevents problems by solving with data analysis to achieve
the goal of better efficiency. The final step is the verify
process which involves continual monitoring if the project is
already in place, or simulation to ensure that the future
project will operate smoothly[3].
If one wishes to implement the Six Sigma process in
their line of work, then one must follow the methodologies
precisely, in order for it to be effective. Due to the different
stages of a project, there are different processes to follow for
each, which vary only slightly in the last two phases. More
and more emergency departments are looking to Six Sigma
to improve their efficiency, because of its past success at
other hospitals.
IMPLEMENTING SIX SIGMA
While all of the methodologies and tools seem to work in
theory, often times they fail to take hold in the actual work
force. Part of this problem is excuses and a lack of
motivation on the part of the employees. Employees feel that
they are doing the best they can and blame others for any
failures. When someone comes in preaching “Near
Perfection,” they are rightly skeptical. They have been
through many training and improvement seminars and
believe that this is just the newest annoyance that
management is forcing upon them. Lean Six Sigma has a fail
rate of 50% within the first three years [1] simply because
the implementation does not maintain a firm hold in the dayto-day practices of the employees.
In order to ensure that Lean Six Sigma takes root, an
implementation team must be formed of the most highly
motivated and dedicated employees; people that want to find
ways to improve. This team will spearhead the effort
towards having a working environment free of waste and
operating at Six Sigma. This team will be the highest level
of the hierarchy of improvement. For example, in a hospital
this team should be those in management positions of the
different departments and the executives of the hospital.
From there, each representative should have their own
smaller team within their departments. As in the case of the
Emergency Department, one nurse or doctor from each shift
should be present at meetings to discuss problems they see
during their rounds. These teams should follow the processes
LEAN SIX SIGMA: CASE STUDIES
In order to garner a full understanding of what Lean Six
Sigma does and how it works case studies are important to
look at. An interesting case study done in St. Mary’s
Hospital in Hoboken[7], New Jersey focuses on how Six
Sigma was able to improve the outcomes for patients that
presented abdominal pain to ED doctors. The team first
focused on a problem and created the following problem
statement: “Cases presenting to ED with acute abdominal
pain experience a delay in diagnosis of appendicitis resulting
in over use of services, misdiagnosis and a delay in surgical
intervention.” Dr. Christopher Valerian, a Six Sigma Black
Belt, spearheaded the team. The team took on this project
with a goal of lowering the length of stay of patient from
four to two days and determined that to achieve this goal
they must have an early surgical intervention of about six
hours while still in the Emergency Department. The problem
5
Brandon D’Aloiso
Seth Young
After the implementation of their protocols the team
collected new data on length of stay (Figure 4) and hours
until surgery (Figure 5) are as follows.
As seen from the data, using Six Sigma they were able to
get the average length of stay in the ED down to 2.6 days
and the average hours until surgery were almost cut in half
to about 10.8 hours[7]. The team came very close to their
original goal and was successful thanks to Six Sigma. Not
only did the team create great improvements for patients but
also saved the hospital about $153,000.00 annually[7]. They
also found that their new triage and registration processes
were so successful that other hospitals took them on as well.
From the data of the hospital it is pretty clear that Six
Sigma is a successful continuous improvement program, but
what about Lean? In the Annals of Emergency Medicine, an
experiment was performed to see to what degree Lean
Process Improvement actually boosts ED productivity using
the variables of length of stay(LOS), patient satisfaction
(PS), percentage of people who left without being seen
(LWSD), time for test results to come back, and patient
volume changes (PV)[8].
with just shortening the decision time however is the fact
that it is unsafe for the patient. In addition to keeping the
diagnostic and intervention process safe, the hospital ED
would save money by shortening the length of stay of their
patients and earn more money by allowing new patients to
come in at a larger rate. The team collected and analyzed
data on two factors; length of stay (LOS) (Figure 2) and
hours from entering the ED to their surgery (Figure 3).
As can be seen from the Valerian team’s data, the
average number of hours until surgery was at 21.6 hours and
the length of their stay was about 4 and a half to 5 days. The
team next outlines their possible solutions. They suggest that
by creating both a new triage process and a new door to
surgery protocol they can shorten the time that the patient
spends in the hospital before and after surgery to a
minimum. Also the team suggests that the type and number
of diagnostic tests that should be performed should be
standardized in order to assure that the patient only has to
wait for the required tests rather than waste time waiting on
tests that were not necessary in the first place.
Descriptive Statistics
Descriptive Statistics
Variable: LOS
Variable: LOS
Anderson-Darling Normality Test
A-Squared:
P-Value:
1
3
5
7
Mean
StDev
Variance
Skewness
Kurtosis
N
9
Minimum
1st Quartile
Median
3rd Quartile
Maximum
95% Confidence Interval for Mu
0.361
0.412
Anderson-Darling Normality Test
A-Squared:
P-Value:
4.47619
2.50238
6.26190
0.538963
-2.4E-01
21
1.0000
2.0000
4.0000
6.0000
10.0000
1
2
95% Confidence Interval for Mu
3.3371
3
4
5
6
3
4
5
Mean
StDev
Variance
Skewness
Kurtosis
N
6
Minimum
1st Quartile
Median
3rd Quartile
Maximum
95% Confidence Interval for Mu
5.6153
1.96577
3.6136
2.0
2.5
3.0
3.5
2.6735
3.39787
95% Confidence Interval for Sigma
95% Confidence Interval for Median
95% Confidence Interval for Median
1.00000
1.00000
2.00000
4.25000
6.00000
95% Confidence Interval for Mu
95% Confidence Interval for Sigma
1.9145
1.280
0.002
2.68182
1.61500
2.60823
0.721144
-7.8E-01
22
1.24250
6.0000
2.30794
95% Confidence Interval for Median
95% Confidence Interval for Median
FIGURE 2
1.97268
3.02732
FIGURE 4
Pre-Six Sigma Data on the Variable Length of Stay[7]
Post-Six Sigma Data on the Variable Length of Stay[7]
Descriptive Statistics
Descriptive Statistics
Variable: Hours
Variable: Hours
Anderson-Darling Normality T est
A-Squared:
P-Value:
0
20
40
60
80
100
95% Confidence Interval for Mu
1.928
0.000
Mean
StDev
Variance
Skewness
Kurtosis
N
21.6162
21.1075
445.528
2.87249
10.0976
21
Minimum
1st Quartile
Median
3rd Quartile
Maximum
4.500
9.705
17.080
25.540
100.830
Anderson-Darling Normality T est
A-Squared:
P-Value:
2.5
7.5
12.5
17.5
Mean
StDev
Variance
Skewness
Kurtosis
N
22.5
Minimum
1st Quartile
Median
3rd Quartile
Maximum
95% Confidence Interval for Mu
12.008
10
20
30
95% Confidence Interval for Mu
31.224
8.3320
30.481
6
95% Confidence Interval for Median
95% Confidence Interval for Median
10.901
2.2000
5.9975
9.7100
15.1600
23.9200
95% Confidence Interval for Mu
95% Confidence Interval for Sigma
16.149
0.496
0.192
10.8036
5.5745
31.0752
0.577669
-2.7E-01
22
7
8
9
10
11
12
13
14
15
13.2752
95% Confidence Interval for Sigma
4.2888
20.635
7.9663
95% Confidence Interval for Median
95% Confidence Interval for Median
FIGURE 3
Pre-Six Sigma Data on the Variable of Hours to Surgery[7]
6.1286
FIGURE 5
Post-Six Sigma Data on the Variable Hours to Surgery[7]
6
14.2254
Brandon D’Aloiso
Seth Young
THE ANSWER
Lean Six Sigma has been tried and tested by the healthcare
system in recent years, and has been successful in those
trials. Because of the many different types of waste found in
an emergency department, the need for creating Lean
Healthcare systems is a necessity. Once a Lean system is
created, it is up to Six Sigma to boost productivity of that
system and ensure the safety of patients. The primary goal
of this revolutionary process in emergency departments is
not to increase profit, but rather to improve upon patients’
health by minimizing waste and defects, and by decreasing
the overall time spent waiting. This proven and effective
process is available to emergency departments immediately.
An ED that is trying to reform its practices but chooses to
dismiss Lean Six Sigma is being simply counterproductive.
If emergency departments were to use Lean Six Sigma, a trip
to the emergency room would no longer be seen as an
inconvenient process but as a healing opportunity.
Each of these hospitals were measured for these variables
for one year before Lean was implemented and asked that in
implementing Lean they hire a Lean consultant to hold a 3-5
day training session for the staff. While all different, each of
the training sessions taught inherently the same content. The
staff learned Lean to the same levels and was prepared to
implement it to the same effectiveness. They were told that a
third party data recorder would be in to collect the data for
the study[8]. They were to proceed with Lean for one year or
until it was no longer effective. A chart of the Pre-Lean and
Post-Lean data is below (Table II).
TABLE II
Lean Healthcare Trial Results[8]
REFERENCES
[1] J. Arthur. (2011). Lean Six Sigma for Hospitals. New York, NY: The
McGraw Hill Companies.
[2] M. Graban. (2009). Lean Hospitals. New York, NY: CRC Press.
[3] “Six Sigma Online.” Aveta Business Group Belt Certification. [Online]
Availible: http://www.sixsigmaonline.org/six-sigma-white-belt-training/
[4] Z. Ben Atallah and A. Ramudhin, (2010, December). “Improving
Healthcare Reliability by Integrating Six-sigma in a Buisness Process
Medeling and Analysis Strategy.” International Conference on IEEM.
[Online].
Available:
http://www.engineeringvillage2.org/controller/servlet/Controller?CID=quic
kSearchDetailedFormat&SEARCHID=19a02031351190876cMa04prod2da
ta2&DOCINDEX=1&database=7&format=quickSearchDetailedFormat
[5] T. Pyzdek. (2003). “Six Sigma Training From the Source.” [Online].
Available: www.sixsigmatraining.org/dmaicdmadv
[6] (2012) UPMC Mercy Hospital. Pamphlet/Poster.
[7]Valerian, Christopher. (2004). “Six Sigma in Healthcare: Redefining the
Emergency Room Process.” Healthcare Information and Management
Information System Society:The Virgina Chapter. [Online]. Available:
http://www.vahimss.org/index.html
[8] Z. Anguelov, E. D., A. Eller, S. Singh and Diana Vetterick (2009). "Use
of Lean in the Emergency Department: A Case Series of Four Hospitals."
The Annals of Emergency Medicine.
[Online]. Availible:
http://www.sciencedirect.com/science/article/pii/S019606440900287X
The hospitals were able to revolutionize their practices in
the ED and Lean is what helped them to do that. Seeing
patient satisfaction levels dropping is never a good sign but
as the data was collected over a wide range and in different
types of hospitals (2 large, teaching hospitals, 2 acute care,
smaller hospitals) this fall in data points for patient
satisfaction can be related to many uncontrollable variables
and is not something to be focused upon.
As seen so far, Lean Healthcare and Six Sigma practices
help hospitals and their emergency departments. To find
research on Lean Six Sigma in Emergency Departments and
to cite studies that relate to both methodologies used
together would be very hard to do. A lot of the research done
on this pairing so far does not relate to healthcare. The
practices are out there and it has been implemented, but no
major studies have been done to comment on Lean Six
Sigma for Healthcare’s tested effectiveness. Lean has been
proven to be effective and so also has Six Sigma. The two
practices share the same goals, complement each other in
their processes, and have the potential to revolutionize
emergency departments everywhere that use them.
Therefore, the effectiveness of Lean Six Sigma cannot be
disputed as a pair; as long as implementation is successful
and lasting, they will be successful in all applications.
ADDITIONAL RESOURCES
Z. Anguelov, E. D., A. Eller, S. Singh and Diana Vetterick (2009). "Use of
Lean in the Emergency Department: A Case Series of Four Hospitals." The
Annals
of
Emergency
Medicine.
[Online].
Availible:
http://www.sciencedirect.com/science/article/pii/S019606440900287X
J. Antony, B. Sezen, and M. Tanner. (2007). “An Overview of Six Sigma
Applications in Healthcare Industry.” International Journal of Health Care.
[Online]. Available: www.emraldinsight.com/0952-6862.htm.
J. Arthur. (2011). Lean Six Sigma for Hospitals. New York, NY: The
McGraw Hill Companies.
Z. Ben Atallah and A. Ramudhin, (2010, December). “Improving
Healthcare Reliability by Integrating Six-sigma in a Buisness Process
Medeling and Analysis Strategy.” International Conference on IEEM.
[Online].
Available:
http://www.engineeringvillage2.org/controller/servlet/Controller?CID=quic
kSearchDetailedFormat&SEARCHID=19a02031351190876cMa04prod2da
ta2&DOCINDEX=1&database=7&format=quickSearchDetailedFormat
M. Graban. (2009). Lean Hospitals. New York, NY: CRC Press.
7
Brandon D’Aloiso
Seth Young
R. Holden, (2011, March). “Lean Thinking in Emergency Departments: A
Critical Review”, Annals of Emergency Medicine, [Online]. Available:
http://www.sciencedirect.com/science/article/pii/S0196064410013223
R. Lazurus, Ian, and Wendy M. Novicoff. (2004). “Six Sigma Enter the
Healthcare Mainstream” Managed Healthcare Executive. [Online].
Available:
http://search.ebscohost.com/login.aspx?direct=true&db=bth&AN=1206264
5&site=ehost-live.
M. McClay, (2010, January). "Improving The Hospital Discharge Process
With Six Sigma Methods." Quality Engineering. [Online]. Available:
http://web.ebscohost.com/ehost/pdfviewer/pdfviewer?sid=84dd5c5d-6b9a4a7c-88f3-5e2608a5fca3%40sessionmgr12&vid=2&hid=8
M. Pepper and T. Spedding. (2009, October). “The Evolution of Lean Six
Sigma.” International Journal of Quality & Reliabiliy Management.
[Online]. Available: www.emeraldinsight.com/0265-671X.htm.
T. Pyzdek. (2003). “Six Sigma Training From the Source.” [Online].
Available: www.sixsigmatraining.org/dmaicdmadv
“Six Sigma Online.” Aveta Business Group Belt Certification. [Online]
Availible: http://www.sixsigmaonline.org/six-sigma-white-belt-training/
(2012) UPMC Mercy Hospital. Pamphlet/Poster.
Valerian, Christopher. (2004). “Six Sigma in Healthcare: Redefining the
Emergency Room Process.” Healthcare Information and Management
Information System Society:The Virgina Chapter. [Online]. Available:
http://www.vahimss.org/index.html
ACKNOWLEDGMENTS
In writing this paper we contracted the help of many
individuals and we wish to thank them now; thank you Dr.
Carter Davidson and Nurse Amy Gerwig. We could not have
done this without your help. Also thank you to the librarians
in the Falk Library and Bevier Engineering Library, your
assistance in finding sources was very appreciated. Also, we
would like to thank our session chair, Professor Vidic, and
co-chair, Taylor Robinson for both of your help. Your
guidance and feedback really has allowed us to do our best
on this paper. Finally a large thank you goes out to Dr.
Budny and his helpers behind the scenes who put together
this wonderful opportunity.
8