Six Sigma Project

1. Wait Time
Reduction Project
By Andrew Phillips
July 16, 2012

2. Situation
 Three (3) new Medical Oncologists (Doctors) joined the practice six weeks ago,
increasing the number of Medical Oncologists at the Practice from 5 to 8. Since the
addition of the 3 new oncologists, patient wait times for Exam visits have risen sharply
from an average of 13 minutes to 31 minutes. This is a 140% increase.
 Reduce average wait time to x number of minutes (see what the customer would like
to see as a minimum, an average, and maximum wait time.)
 The patients are scheduled in 15 minute intervals for each physician.
 There was increase from 140 to 224 opportunities for patients. This represents a 60%
increase in patient load.
 Assumption: Percentage of the number of patients per physician was constant.
 The laboratory employs 3 full time phlebotomists who draw blood, and each draw takes
7.5 minutes on average.
 Assumption: The Laboratory will need another 10 minutes to deliver the results to the
physician.
Copyright © 2010 US Oncology, Inc. All rights reserved. 2

3. Problem
 The patients have complained about the increase wait time.
 This backlog increases throughout the day which causes
overtime and working through lunch and breaks.
 Patients may leave, causing decrease in revenue.
 Workers are overworked.
Copyright © 2010 US Oncology, Inc. All rights reserved.

4. Measurements
 Using Lean Six Sigma tool set of statistics analysis see how to
better manage the patient flow and find solutions
 Map the process with Swim lanes.
 Develop a CTQ tree to see what is important to the customers
 Measure Lab process times and the time it takes to get the data
to the physician.
 Individual Moving Range (IMR) chart – showing the variance in
the process and how we can reduce the variance. This is using
variable data and sample size of 1.
 Measure the wait times more closely and see if there is a
correlation between physician and number of patients scheduled.
Copyright © 2010 US Oncology, Inc. All rights reserved.

5. 8 :0
0
1
2
3
4
5
6
7
8
9
0A
8 :1 M
5A
8 :3 M
0A
8 :4 M
LCL=2.4188
UCL=8.1329
CEN=5.2759
5A
9 :0 M
Copyright © 2010 US Oncology, Inc. All rights reserved.
0A
9 :1 M
5A
9 :3 M
0A
9 :4 M
5A
10 M
:00
10 AM
:15
10 AM
:30
10 AM
:45
11 AM
:00
11 AM
:15
11 AM
:30
11 AM
:45
12 AM
:00
12 PM
:15
Individuals Chart
12 PM
:30
12 PM
:45
P
1 :0 M
0P
1 :1 M
5P
1 :3 M
0P
1 :4 M
5P
2 :0 M
0P
2 :1 M
5P
2 :3 M
0P
2 :4 M
5P
3 :0 M
0P
3 :1 M
5P
3 :3 M
0P
3 :4 M
5P
4 :0 M
Individual Moving Range Chart
0P
M

6. Current Data Analyses
 Average (Mean) patients per time slot is 5.27.
 Standard deviation is 2.4.
 Total number of patients for the day is 153.
 Total number of time slots is 224.
 Usage 68.3%.
 Mode 7.
 Median 6.
 Average wait time 31 minutes.
 Data needed:
 Wait time per lab process.
 Wait time per drawing blood.
 Wait time per patient/per physician.
 Wait time per patient load.
Copyright © 2010 US Oncology, Inc. All rights reserved.

7. Data Analyses
 Other tools which we need to use:
 Cause and Effect Diagram.
 Design of Experiment (DOE) to see what impacts the wait
time the most.
 Scatter Diagram to show relationship between wait time,
physician, patient load, and time of day.
 Hypothesis testing to prove or disprove any hypothesis.
Copyright © 2010 US Oncology, Inc. All rights reserved.

8. Improve
 Continue collecting data to see if patient wait time has improve.
 Example of how we might improve the patient wait time.
 Increase Average (Mean) patients per time slot is 5.27 to 6
 Hire 1-2 phlebotomists.
 Increase total number of patients 194 74% usage instead of
58.8% (48% increase)
 Reduce - Standard deviation from 2.4 to 1.
Copyright © 2010 US Oncology, Inc. All rights reserved.

9. Control
 Document new process and new procedures for reduced wait
time.
 Communicate this to customers as well as physicians and
workers.
 Communicate improve and savings to everyone.
 Share success.
Copyright © 2010 US Oncology, Inc. All rights reserved.

10. Process Map
Copyright © 2010 US Oncology, Inc. All rights reserved.

11. 8 :0
0
1
2
3
4
5
6
7
8
9
0A
8 :1 M
5A
8 :3 M
0A
8 :4 M
LCL=2.4188
UCL=8.1329
CEN=5.2759
5A
9 :0 M
Copyright © 2010 US Oncology, Inc. All rights reserved.
0A
9 :1 M
5A
9 :3 M
0A
9 :4 M
5A
10 M
:00
10 AM
:15
10 AM
:30
10 AM
:45
11 AM
:00
11 AM
:15
11 AM
:30
11 AM
:45
12 AM
:00
12 PM
:15
Individuals Chart
12 PM
:30
12 PM
:45
P
1 :0 M
0P
1 :1 M
5P
1 :3 M
0P
1 :4 M
5P
2 :0 M
Individual Moving Range
0P
2 :1 M
5P
2 :3 M
0P
2 :4 M
5P
3 :0 M
0P
3 :1 M
5P
3 :3 M
0P
3 :4 M
5P
4 :0 M
0P
M