See attachment page 4 and 5 ONLY

A Lean Six Sigma Case Study

If you want to prosper for a year, grow rice. If you want to prosper for a decade, plant trees. If

you want to prosper for a century, grow people — a wise old farmer reflecting back on a life

of toil in the soil

PROJECT DESCRIPTION

The following Lean Six Sigma case study will reflect a real-life healthcare problem with

Continuous Improvement and Lean Six Sigma Tools to show how some of the tools are put into

place in the real world. The object of this project is your appropriate use of Lean Six Sigma

tools and the data provided. Project completion is required to pass the course. Project

assignments are assessed on a Complete/Incomplete basis. Each Phase of the DMAIC process in

the Project has an assignment. Assignments must be submitted to the instructor by the end of the

week corresponding to the DMAIC Phase. The exception is the week 8 or Control phase

assignment which needs to be submitted early in the last week of the course to allow grading.

The Instructor will determine if the student has submitted a Project assignment that is Complete.

If the assignment is Incomplete, there will be interaction between the Instructor and student until

the assignment is Complete. All project assignments must be assessed as Complete for the

student to pass the course. An Incomplete project will result in a Failing grade for the course.

Student Case Study

Case Study:
Process Improvement –
Reduction in Wait Time for
Patients in a Doctor Office

Executive Summary
Dr. Deasley is a popular Doctor in Tampa, Florida specializing in primary care. He spends a great deal of
time with each of his patients, typically, 45 minutes to one (1) hour. As a result, there are many other
patients waiting in the waiting room who become impatient at the long wait time. The Doctor has hours
every day except Wednesdays. He has Hospital Clinic on Wednesdays and does not have office hours.
Dr. Deasley’s office hours are 7:30 AM to 5:30 PM (patients can be scheduled up until 5:30 PM) on
Tuesdays and Thursdays and 9:30 AM to 7:30 PM (patients can be scheduled up until 7:30 PM) on
Mondays and Fridays. He does Hospital Rounds from 6:00 AM to 8:00 AM. He conducts patient call
backs between patients, during his lunch hour and after office hours. We triage the calls so he gets back
to more seriously sick patients first. However, sometimes he doesn’t call back non-emergencies until the
next AM. Dr. Deasley is becomes overbooked because he likes to have 10 patients scheduled per day.
However, due to time constraints he frequently needs to rebook patients he is unable to see due to time
constraints.

Dr. Deasley’s patients and staff love him for his patience and attention. But, several long term patients
have left his practice because of this issue. This has resulted in a decrease in revenue for the office. In
addition, his office is experiencing a rather high rate of staff turnover. Staff are responsible for booking
patients and managing the workflow in the office. When backlogs occur and patients become annoyed
about wait times, the staff usually experience the brunt of the patient dissatisfaction, which effects staff
morale. Each time the office hires replacement staff, it takes a significant amount of time to train new
employees and it is costly to advertise and recruit competent staff. Dr. Deasley is very concerned about
both his patients and staff.

His Office Manager, Ms. Smith, who recently was employed at Memorial Hospital of Tampa, participated
in several Continuous Improvement Projects at the hospital. She is a certified Lean Six Sigma Green Belt.
As a result, Ms. Smith has suggested a plan to the doctor to conduct a Lean Six Sigma project with the
objective of Reducing Patient Wait Time and Improving Office Workflow. Ms. Smith explained the
project improvements and objectives. Dr. Deasley has approved the project. As an initial step, the Office
Manager has established her team. Each employee has a role in the project. Based on patient
complaints and the doctor’s requirements, they have some initial Voice of Customer (VOC). Patients
would like to see the Doctor within 10 minutes of arriving and spend no more than 30 minutes in the
office total for routine visits. The Doctor would like to see 15 patients per day. These changes need to
be made within 3 months in order to minimize patient dissatisfaction, stop patients leaving the practice
due to long wait times and rescheduling and improve employee morale and retention.

Define
1. Complete a Project Charter with all of the required Information

a. Please write the Problem Statement:
b. Please write the Goal Statement utilizing S.M.A.R.T. objectives (Specific,

Measureable, Attainable, Relevant and Time Bound):
c. What is in Scope? What is out of Scope?
d. Who are Key Stakeholders?
e. What are key Milestones?

2. Please complete a High Level “As Is” Process Map.
3. Please create a SIPOC of the process based on the information that you know. Feel free to

use your imagination for this.
a. Describe methods for collecting Voice of the Customer. (SEE APPENDIX A for VOC)

4. Please create an Affinity Diagram or List based on VOC so you can identify Customer
“NEEDS” for CTQ Tree

5. Please create a Critical to Quality Tree utilizing the Voice of the Customer. Identify the
Needs, Drivers and Requirements or Metric to needed to meet these needs

Conclusion of Define: The output of the DEFINE stage is a PROJECT CHARTER (PC) and
STAKEHOLDER ANALYSIS (SA). The PC shall include a Problem Statement with Goals
utilizing S.M.A.R.T. methodology to address the problems identified. The Goal shall be
aligned with the customer CTQ Requirements. A clearly defines SCOPE is included in
the PC. What is IN SCOPE and what is OUT OF SCOPE? Your Team is identified and
Roles & Responsibilities are defined. A SIPOC Map is completed. An “As Is” Process
Map is completed in order to better visualize the Work Flow in the current process. The
DEFINE Phase provides for identification of the VOC and CTQs, their needs, Drivers and
Requirements. The student will have evaluated and Affinitized the VOC. CTQ trees
were created to identify key requirements for meeting the customer’s needs. The
Project Team should have a list of external Key stake Holders, if applicable, e.g.,
Hospital Radiology, who may be impacted by process changes within the Doctor’s
medical practice. If the Doctor’s staff schedule testing appointments for patients and
are required to make frequent changes, this has an impact on the department or
entity conducting the testing. The Project Team will have met with Dr. Deasley for his
approval to proceed and now has a baseline to begin the Measure phase.

Measure
1. Based on Customer requirements the project team collected initial data. Use Pareto Analysis

of # occurrences data to determine the 5 factors which are causing over 95% of the problem
with wait time. You need to determine the ‘biggest contributors to the problem. One tool to
accomplish this is the Pareto Chart. You need to know if it is reasonable to assume that
these five ‘parameters’ are normally distributed. (SEE APPENDIX B)

a. Based on Pareto Analysis what are the focus areas?
b. Set up appropriate methods for tracking focus areas. You will need to track # of

occurrences of each category and actual for measuring the ability to meet the
requirements.

2. Define your Data Collection Plan. Include the types of data you will be collecting (Discrete or
Continuous), Why? (In many instances you will have a mix of both types of data depending
on the Data source.

3. Based on the data collected Construct FIVE (5) histograms for the below data sets. (SEE
APPENDIX C) for data sets

a. Interpret each of the histograms to determine whether the assumption of normality
is reasonable.

b. If the data are not approximately normally distributed, why not?
4. The team also believed there was a Motorola shift during the process. Please describe the

Motorola Shift and potential causes that they could have experienced the shift.
a. Calculate the PPM/DPMO for this process and determine the baseline sigma with

the Motorola shift.
5. Calculate the Process Performance, Pp and Ppk, based on the current process. Student will

be able to compare current Process performance to Capability Study performed for process
improvements. Tint: drawing a picture of the data based on a Normal Curve may help
student visualize if data is skewed when evaluating population distribution. Use UCL = 60
minutes and LCL = 0 Minutes. In Healthcare LCL will frequently be “O”

Conclusion of Measure: A Data Collection Plan was created. Data was taken of as many
parameters as possible before changing any variables. Key Data has been provided for your
use as directed in the instructions above. Pareto harts have been created and based on the
VOC. The 5 Largest Contributing Factors will have been identified. These should have aligned
with the data provided. A method for tracking data to capture for analysis should have been
identified even if the actual data is already provided. Then from the categories and data

“collected”, 5 Histograms should have been created along with the narrative for Analysis,
specifically related to determination if data was normally distributed. An explanation of the
Motorola Shift is provided. PPM/DPMO is calculated. Pp/Ppk are calculated and current
process Sigma Level is defined. It was found that Dr. Deasley was spending more time with his
patients than necessary. The process needs to be analyzed based on the data.

Analyze
1. Create a Stem and Leaf Plot for the downtimes that were captured from the patient wait times

in the waiting rooms. (SEE APPENDIX D for data set)
2. Calculate Measures of central Tendency with Downtime data. What can you interpret from

these measures? Please document a conclusion (SEE APPENDIX D for data set)
3. Calculate Measures of Dispersion with Downtime data. What can you interpret from these

measures? Please document a conclusion (SEE APPENDIX D for data set)
4. Two individual staff members were being observed performing identical activities in the

Doctor’s office. 25 random samples were taken for each staff member. One of the Medical
Assistants is a new employee. Medical Assistant #1 has been with Dr. Deasley for several years.
Medical Assistant #2 is a new employee and has been with this medical practice for 9 months.
We want to determine how Assistant 2 performs when compared to Medical Assistant #1. Since
she is a new employee. (SEE APENDIX E for data sets)

5. Please provide the following information based on your analysis of the two Medical Assistants
a. Medical Assistant #2 Average
b. Medical Assistant #2 Standard Deviation
c. Null Hypothesis
d. Alternative Hypothesis
e. T-Test Statistic
f. Critical Value
g. Statistical Conclusion for the null and alternative hypothesis.

Conclusion of Analyze: Stem and Leaf Plots were created from Downtime data provided, Measures of
Central Tendency were also determined using Downtime data and an interpretation of the results
were made. Data was analyzed to review if different staff members were performing similarly or not.
Students should have established a Null Hypothesis and Alternative Hypothesis from the data for the 2
staff members. An appropriate test was performed and conclusions made based on the outcome.

IMPROVE
1. A staff member has been stating for months that there is a correlation between the Room

Availability and the Patient arrival time. Should the Office Manager have listened to this staff
member’s observation? After completing items 2 through 5, provided your thoughts on staff
observations and how they might have achieved Office Manager Buy-In sooner.

2. Construct a scatter diagram and calculate the correlation coefficient to see if she is correct. SEE
APPENDIX F for data set

a. Is there strong correlation between room availability and patient arrival time?
b. IF there is strong correlation, is it positive or negative? (Answer with positive, negative

or N/A)
c. What is the correlation coefficient between the two variables? (Use 6 decimal places).

What does this mean?
3. Discuss the 8 Deadly Wastes (MUDA) of the process.
4. Create a Fishbone Diagram. List Potential Root Causes. Narrow Potential Root Causes to Key

Root Causes. Explaining some of the key Root causes.
5. Discuss Improvements that you would suggest based on findings from FISHBONE Analysis.

Conclusion of Improve: A Scatter Plot was constructed and a Correlation completed. The
determination of whether the 2 factors Correlate based on a Correlation Coefficient determination is
stated and comments on whether the correlation is Positive or Negative are included. 8 Wastes were
evaluated and identified where applicable. A FISHBONE DIAGRAM was created and many ideas were
brainstormed for Potential Root Cause. These were then narrowed to the critical few Root Causes.
Many improvement suggestions were made.

CONTROL
An I-MR chart was plotted for the Doctor’s office to ensure the specifications were performing as
planned and the patients and Doctors were satisfied.

1. Please indicate if the control chart is stable and if any Shewhart Rules have occurred.

2. A normality test was conducted. Please advise if the data is normal.

3. A capability study was completed. Please advise if the process is stable and any analysis you

find is relevant.

4. Please complete a Control and Monitoring Plan for the project.
5. Create a Dashboard which the office can utilize to monitor the performance of the

improvements as well as supporting the sustainability of the improvements

Conclusion of Control: Conclusion regarding the stability of the Control Chart was made and any
violations of the Shewhart Rules were noted. Students then observed the WET LAB TESTING and
discussed the Normality of the data. A Capacity Study was done presumably using data from
improvements made and analysis of the Mini Tab output was discussed. A Control and Monitoring
Plan was created to ensure monitoring of improvements for Sustainability. Final a Dashboard was
developed to be used for staff to visually track their performance and for discussion with Dr. Deasley.
We have collected data after making many improvements to see if the process is now stable. We will
continue to monitor our progress and follow the control plan.

>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

 Please make final conclusions of the project.

APPENDIX A: VOICE OF THE CUSTOMER

Feedback from Patients:

I wait too long. I only have an hour for Lunch. I make my appointments specifically at Lunch
time because I can’t come after work.

I like to come very early and be one of Dr. D’s first patients. If I am not his 1st, I end up waiting
and am late for work. My company is very strict about being on time.

I wouldn’t mind if the doctor spent less time with me. I only usually come for an Annual
Checkup and a Flu shot. If I feel really sick, I call the office. When I broke my arm last year, the
doctor sent me right to the hospital. You guys made the arrangements for my X-Ray so I didn’t
need to wait.

I can’t be late when I come in the afternoon. I need to pick my daughter up from school. If I
come in the afternoon, can you make it a short visit?

The doctor spends so much time asking me questions, can’t he look at my chart before I get
into the exam room?

The last time I was here, you put me in a room with someone else’s clothes. The woman had
gone to the Ladies’ room and came back to get dressed. I had to wait in the hallway.

Feedback from Staff

We need to organize the exam rooms. Dr. Deasley is always looking for something and I need to
go find it.

We can’t have multiple people at the Front desk assigning patients to rooms. They don’t always
assign patients to the right room and equipment is not available

Dr. D keeps taking equipment with him from room to room,

The patients are not getting here early enough to get them ready for the doctor. He like to have
their Blood Pressure, Weight and Temperature done before he comes in.

Patients keep arriving the last minute, then they get angry because they miss their appointment
and need to wait.

I hope I never have to reschedule Mrs. Smyth for a new appointment because the doctor
couldn’t see her. She was practically screaming at me.

We had 2 patients, Mrs. Jones and Mr. Thomas ask for their records to be sent to a new
doctor’s office. That is the 4th time that has happened this year and we are only ½ way through
the year.

The new Medical Assistant was complaining because she said there is too much chaos here. I
think she might be sorry she came her. I hope she doesn’t go back to the hospital. It takes so
much time to find good people and train them.

Feedback from Doctor

I don’t always have the instruments I need in the Exam Room. I need to have my Assistant go
find what I need. I’ve started taking Instruments with me to my next patient only to find 3 of
the same instrument I am carrying in the next Exam Room.

I have seen several patients waiting in the hall outside the Exam Room. I don’t like that
situation. We need to stop this practice.

I see some staff running around like crazy and others sitting around appearing to have nothing
to do.

I am not one of these “hands off’ doctors, I like to spend time with my patients. But sometimes
a patient will sit there with nothing to say and another patient will have a long list of issues.

If this improvement project is successful, I would like to see 15 Patients a day. We need to keep
operating costs in mind. We need to keep our equipment up to date and I need to ensure we
plan for salaries and bonuses at year end.

I notice we have had 3 people leave within the past 18 months. I would like to understand why.
It is very expensive to recruit staff and it takes time before they are proficient in their jobs. The
team we have now is very good. I would like to keep all of them. We do monitor salaries and
compare with market standards so I know our salaries and benefits are competitive.

Feedback from Other Sources

Radiology Department is complaining because they state we make too many changes to the
patient appointments.

The Laboratory department is complaining because our patients are coming for testing outside
their assigned appointment time and too late in the day.

APPENDIX B: Based on VOC data to be used to construct CTQ’s. Project Team will
identify key focus areas in Doctor’s Office using Pareto Diagram. These focus
areas will then be monitored as defined in Data Collection Plan.

Time the Doctor was spending with Patients – 79

Number of times Dr arrives late – 4

Proper Medical Devices not Available – 30

Number of times patient is left in the hallway – 17

Rooms Available at Doctor’s Office -22

Number of times staff arrive late – 3

Staffing of Doctor’s Office -41

Number of times scheduling changes were made for patient testing – 15

Number of times patient had to be rescheduled for Dr visit – 10

Arrival Time of Patients – 52

APPENDIX C: Data set to be used to construct 5 Histograms

Proper
Medical
Devices

N/A

Rooms
Available

at Dr.
Office

Staffing at
Dr. Office

Arrival
Time of
Patients

Time Dr.
Spends

with
Patients

10.82 7.45 0.5502 172 48

10.82 7.55 0.5522 169 34

10.86 7.67 0.546 177 23

10.87 7.65 0.5462 170 32

10.84 7.62 0.5491 174 19

10.85 7.59 0.5486 175 37

10.86 7.6 0.5428 167 20

10.87 7.52 0.5532 171 47

10.89 7.49 0.5472 168 27

10.8 7.54 0.5522 172 31

10.81 7.52 0.5494 168 44

10.89 7.61 0.5519 163 27

10.81 7.52 0.5509 174 61

10.9 7.61 0.5412 169 17

10.87 7.53 0.5518 171 26

10.86 7.57 0.5523 172 50

10.85 7.59 0.5415 172 11

10.85 7.55 0.5477 168 53

10.86 7.61 0.553 169 18

10.86 7.54 0.55 166 75

10.83 7.57 0.5437 172 27

10.89 7.51 0.5463 168 36

10.76 7.63 0.5566 174 40

10.78 7.5 0.541 175 30

10.86 7.58 0.5542 164 23

10.9 7.55 0.5569 173 15

10.83 7.51 0.5432 168 15

10.82 7.5 0.5487 170 35

10.87 7.59 0.5537 173 45

10.88 7.58 0.541 170 25

10.67 7.64 0.5554 173 42

10.72 7.48 0.5521 167 64

10.65 7.57 0.5532 169 23

10.7 7.46 0.5563 172 53

10.67 7.53 0.5508 165 50

10.65 7.6 0.5527 170 16

10.6 7.49 0.5546 169 41

10.66 7.65 0.5478 170 7

10.61 7.55 0.5468 165 31

10.69 7.55 0.5566 172 18

10.71 7.51 0.5531 168 53

10.66 7.49 0.5482 173 34

10.64 7.49 0.5473 172 37

10.62 7.49 0.5442 170 80

10.63 7.56 0.5491 176 19

10.67 7.59 0.5596 175 26

10.62 7.47 0.5491 170 13

10.62 7.58 0.5507 169 18

10.63 7.55 0.556 177 36

10.65 7.47 0.5428 178 7

10.68 7.63 0.5488 172 34

10.68 7.47 0.5531 171 28

10.63 7.68 0.5483 171 44

10.68 7.55 0.5431 171 18

10.58 7.47 0.545 177 23

10.59 7.59 0.5392 172 17

10.64 7.57 0.5512 170 25

10.64 7.53 0.5465 169 15

10.68 7.58 0.5479 164 23

10.6 7.6 0.5452 174 21

Upper Spec 11 7.66 0.56 180 60
Lower Spec 10.5 7.45 0.54 165 0

Target 10.75 7.55 0.55 170 20

APPENDIX D: Data represents Wait Time in minutes beyond their scheduled
Appointment Time for the last 70 patients. Use to create Stem and Leaf Plots.

PATIENT
WAITING

TIME

PATIENT
WAITING
TIME
PATIENT
WAITING
TIME
PATIENT
WAITING
TIME
PATIENT
WAITING
TIME
PATIENT
WAITING
TIME
PATIENT
WAITING
TIME

16 15 19 48 14 47 21
16 17 16 45 80 20 46
17 13 26 50 6 71 48
37 47 17 49 49 47 20
47 11 65 63 48 50 64
32 47 15 17 47 95 16
48 38 17 22 48 47 44
21 17 48 10 52 20 82
18 20 16 18 46 50 51
75 49 44 51 48 35 58

APPENDIX E: Data set for determining performance for Medical Assistant #2. The
historical mean for Medical Assistant #1 was .0126.

MEDICAL ASSISTANT #2
Data

MEDICAL ASSISTANT #2
Data

0.009
0.015

0.010
0.011

0.011
0.011

0.011
0.012

0.010
0.008

0.011

0.011

0.013

0.008

0.012

0.010

0.013

0.014

0.012

0.009

0.014
0.011

0.015

0.011
0.012

APPENDIX F: This is the data set for evaluating Correlation between Room
Availability and Patient Arrival

Room # Availability Patient Arrival Time
154 0.554
153 0.553
152 0.552
152 0.551
151 0.549
151 0.549
151 0.548
151 0.548
151 0.548
151 0.547
151 0.547
151 0.547
151 0.547
151 0.547
151 0.547
151 0.546
150 0.546
150 0.546
150 0.546
150 0.546
150 0.546
150 0.545
150 0.545
150 0.545
149 0.545