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.