This document discusses quality tools and techniques, specifically focusing on the 7 basic tools of quality: histograms, Pareto charts, cause-and-effect diagrams, scatter diagrams, control charts, flow charts, and check sheets. Examples are provided for each tool to demonstrate how they are used. The tools are used to analyze processes, identify problems and priorities, determine relationships between variables, and monitor quality over time. Mastering these 7 basic tools is important for continuous process improvement.

1. 7 Tools of Quality
Dr. Lallu Joseph
Quality Manager, CMC Vellore
&
Mr. Rabindranath
Audit Facilitation Officer, CMC Vellore
QUALITY TOOLS AND TECHNIQUES

2. Recap
• Mean - It is a point of reference and also
the central point for measuring variability. The
only disadvantage of the arithmetic mean is
that it is greatly affected by extreme values.
• Median - It is the middle value in a series of
numbers arranged in an increasing order.
– Series odd number - (n+1)/2
– Series even- arithmetic mean of the two middle
values
QUALITY TOOLS AND TECHNIQUES
7 tools of quality

3. Recap
• Mode - Most frequently occurring value
• Variance
σ2 = 1/n [∑xi
2 - (∑ xi)2 /n]
The Standard Deviation, is a simple square root
of the variance.
In a frequency distribution, variance is
calculated by
σ2 = 1/n [∑ fi xi
2 - (∑ fi xi)2 /n]
QUALITY TOOLS AND TECHNIQUES
7 tools of quality

4. Example
Daily control measurements of Potassium were made for
25 days during a particular month
5.7 5.9 5.7 5.7 5.8
5.7 5.8 5.7 5.9 5.8
5.6 5.8 5.8 5.7 5.6
5.8 5.8 5.5 5.6 5.8
5.9 5.7 5.8 5.8 5.8
Average x = ∑ xi /25 = 143.7/25 = 5.748 = 5.75
Variance = 1/25 [∑ xi
2 - (∑ xi)2 /25]
= 1/25 [826.23 – (143.7)2/25]
= 6.06/625 = 0.0097
Standard Deviation = Sq rt of 00.0097 = 0.0985
QUALITY TOOLS AND TECHNIQUES
7 tools of quality

5. Basic tools of Quality for Process
Improvement
“The old seven”
“The first seven”
“The basic seven”
– Quality pros have many names for these tools, first
emphasized by Kaoru Ishikawa the father of “quality
circles.”
– These are diagnostic tools to analyze a process and data
from that process
– They make up the fundamental continuous
improvement toolkit
QUALITY TOOLS AND TECHNIQUES
7 tools of quality

6. 7 Basic Tools of Quality
• Histograms
• Pareto Charts
• Cause and Effect Diagrams
• Scatter Diagrams
• Control Charts
• Flow Charts
• Check sheet
QUALITY TOOLS AND TECHNIQUES
7 tools of quality

7. HISTOGRAM
• It is for illustrating the frequency and the extent for
two variables.
• Histogram is a chart with columns which represents the
distribution by mean.
• If the distribution is normal, the graph is in the shape
of a bell curve.
• If not normal, it may take different shapes based on
condition of the distribution.
• Histogram can be used to measure one variable against
another. There should be two variables.
• Data should be numerical
QUALITY TOOLS AND TECHNIQUES
7 tools of quality

8. When is it used?
• It is used to communicate the distribution of
data quickly and easily to others.
• Help in decision making
• Graphically summarize large data
• Compare performance to expectations or
specifications
QUALITY TOOLS AND TECHNIQUES
7 tools of quality

9. Reasons for dissatisfaction at OPD
# Reasons Number of patients
1 No mike or display board to know the token number 15
2 Problem mixing with ‘follow-up’ patients 25
3 Insufficient doctors 100
4 Insufficient counter Staff 93
5 Staff not following the Queue 12
6 Too many patients at the same time 21
7 Registration time too long 111
8 No name boards of the doctors 13
9 Others 10
10 Total 400
QUALITY TOOLS AND TECHNIQUES
7 tools of quality

10. Histogram
15
25
100
93
12
21
111
13 10
0
20
40
60
80
100
120
No mike or
display
board to
know the
token
number
Problem
mixing with
‘follow-up’
patients
Insufficient
Doctors
Insufficient
Counter
Staff
Staff not
following
the Queue
Too many
patients at
the same
time
Registration
time is too
long
No name
boards of
the doctors
Others
Reasons for dissatisfaction of patients N =400
QUALITY TOOLS AND TECHNIQUES
7 tools of quality

11. Pareto Charts
– Pareto charts are used to identify and prioritize problems to
be solved.
– Vilfredo Pareto, 1800, Italian economist noted “80% of wealth
was held by 20% of population”
– Juran applied the Pareto Principle, stating that 80% variation
in process is by 20% of the variables
– “Vital few” as opposed to “Trivial many”
– 80/20 rule
– Need not be 80/20, could be 75/25 or 70/30 or even 65/35
also and even disproportionate like 75/35.
– The concept is to priorities and address the issue.
QUALITY TOOLS AND TECHNIQUES
7 tools of quality

12. When is it used?
• Looking at data on the frequency of problems
or causes.
• When there are too many problems or causes
and you want to focus on the significant ones.
• When you want to analyze broad causes by
looking at their specific components.
• To effectively communicate to others about
the problem/ data.
QUALITY TOOLS AND TECHNIQUES
7 tools of quality

13. # Reasons
Number of
patients
1 No mike or display board to know the token number 15
2 Problem mixing with ‘follow-up’ patients 25
3 Insufficient Doctors 100
4 Insufficient Counter Staff 93
5 Staff not following the Queue 12
6 Too many patients at the same time 21
7 Registration Time too long 111
8 No name boards of the doctors 13
9 Others 10
10 Total 400
QUALITY TOOLS AND TECHNIQUES
7 tools of quality

14. # Reasons Number of patients
7 Registration Time too long 111
3 Insufficient Doctors 100
4 Insufficient Counter Staff 93
2 Problem mixing with ‘follow-up’ patients 25
6 Too many patients at the same time 21
1 No mike or display board to know the token number 15
8 No name boards of the doctors 13
5 Staff not following the Queue 12
9 Others 10
10 Total 400
Descendingorder
QUALITY TOOLS AND TECHNIQUES
7 tools of quality

15. # Reasons Number of patients
In %
(N=400)
7 Registration Time too long 111 28 %
3 Insufficient Doctors 100 25 %
4 Insufficient Counter Staff 93 23 %
2 Problem mixing with ‘follow-up’ patients 25 6 %
6 Too many patients at the same time 21 5 %
1
No mike or display board to know the token
number
15 4 %
8 No name boards of the doctors 13 3 %
5 Staff not following the Queue 12 3 %
9 Others 10 3 %
10 Total 400
QUALITY TOOLS AND TECHNIQUES
7 tools of quality

16. # Reasons
Number of
patients
In %
(N=400)
Cumulative
frequency
7 Registration Time too long 111 28 % 28%
3 Insufficient Doctors 100 25 % 53%
4 Insufficient Counter Staff 93 23 % 76%
2 Problem mixing with ‘follow-up’ patients 25 6 % 82%
6 Too many patients at the same time 21 5 % 87%
1
No mike or display board to know the
token number
15 4 % 91%
8 No name boards of the doctors 13 3 % 94%
5 Staff not following the Queue 12 3 % 97%
9 Others 10 3 % 100%
10 Total 400
QUALITY TOOLS AND TECHNIQUES
7 tools of quality

17. 28%
53%
76%
82%
87%
91%
94% 97% 100%
0%
20%
40%
60%
80%
100%
0
20
40
60
80
100
120
Registration
Time too
long
Insufficient
Doctors
Insufficient
Counter
Staff
Problem
mixing with
‘follow-up’
patients
Too many
patients at
the same
time
No mike or
display
board to
know the
token
number
No name
boards of
the doctors
Staff not
following
the Queue
Others
Number of patients Cumulative frequency
QUALITY TOOLS AND TECHNIQUES
7 tools of quality

18. 28%
53%
76%
82%
87%
91%
94% 97% 100%
0%
20%
40%
60%
80%
100%
0
20
40
60
80
100
120
Registration
Time too
long
Insufficient
Doctors
Insufficient
Counter
Staff
Problem
mixing with
‘follow-up’
patients
Too many
patients at
the same
time
No mike or
display
board to
know the
token
number
No name
boards of
the doctors
Staff not
following
the Queue
Others
Number of patients Cumulative frequency
Addressing these 3 issues out of 9, will solve 76% of the problems
QUALITY TOOLS AND TECHNIQUES
7 tools of quality

19. Cause and Effect Diagrams
• Dr. Kaoru Ishikawa
• Cause & Effect Diagram (Fishbone or Ishikawa diagram)
• It is a schematic way of relating the causes of variation
in a process
• A drawing to organize the contributing causes to a
problem in order to prioritize, select, and improve the
source of the problem
• Problem (Effect) on the right side and the possible
causes on the left side
• Causes are broadly classified into 5M’s and E
Man (People)
Methods (Policies and Procedures)
Materials (Supplies)
Machine (Equipment)
Money
Environment
QUALITY TOOLS AND TECHNIQUES
7 tools of quality

20. When is it used?
• When identifying possible causes for a problem.
• Identifies areas for collecting data
• Good process knowledge from multiple stake
holders
• Useful for teams: focusing a discussion and
organizing large amounts of information coming
from a brainstorming session.
• Especially when a team’s thinking tends to fall
apart and concentration is lacking
QUALITY TOOLS AND TECHNIQUES
7 tools of quality

21. Schematic
Effect
People /Man
Plant / MachineProcedures / Methods
PoliciesMaterial
QUALITY TOOLS AND TECHNIQUES
7 tools of quality

22. Cause and Effect
Diagram
Registration
time too
long
People /Man
Plant / MachineProcedures / Methods
PoliciesMaterial
Staff can cut the queue
Registration at any time
Irrespective of appointment time
Manual registration- No
computers
Inadequate signage /
instruction
FIFO not followed
Unnecessary information
being collected at the reg.
counter
New staff
Aggrieved StaffInadequate
stationeries
Separate line for men and
women
QUALITY TOOLS AND TECHNIQUES
7 tools of quality

23. Scatter Plots
• Scatter diagram shows co-relation between
two variables
• If correlated – does not necessarily mean a
direct cause and effect
• If one variable can be predicted based on the
value of the other, then correlated
QUALITY TOOLS AND TECHNIQUES
7 tools of quality

24. Scatter Plots- correlation
• 2 Dimensional X/Y plots (with dots)
• To check if there is correlation b/w two variables
– Used to show relationship between independent(x) and
dependent(y) variables
Positive correlation Negative correlation No correlation
QUALITY TOOLS AND TECHNIQUES
7 tools of quality

25. When is it used?
• Trying to determine if the two variables are
related, such as…
– to identify potential root causes of problems.
– After brainstorming session and identifying causes
and effects using a fishbone diagram, to
determine whether a particular cause and effect
are related.
– To determine whether two effects that appear to
be related both occur with the same cause.
QUALITY TOOLS AND TECHNIQUES
7 tools of quality

26. Time spent by doctor and patient satisfaction
Patient hosp
number
Time Spent by
doctor (In
minutes)
Satisfaction Score
1 24 5
2 8 1
3 9 1
4 22 4
5 10 3
6 19 4
7 10 2
8 16 4
9 13 4
10 15 3
11 23 4
Patient hosp
number
Time Spent by
doctor (In
minutes)
Satisfaction
Score
12 12 3
13 12 2
14 14 3
15 11 2
16 16 3
17 20 4
18 18 3
19 14 2
20 14 4
21 17 3
22 17 4
23 13 3
QUALITY TOOLS AND TECHNIQUES
7 tools of quality

27. Scatter plot
0
1
2
3
4
5
0 5 10 15 20 25 30
Satisfactionscore-5beingthehighest
Time spent by doctors (In minutes)
Satisfaction Score
QUALITY TOOLS AND TECHNIQUES
7 tools of quality

28. Scatter plot
0
1
2
3
4
5
0 5 10 15 20 25 30
Satisfactionscore-5beingthehighest
Time spent by doctors (In minutes)
Satisfaction Score
QUALITY TOOLS AND TECHNIQUES
7 tools of quality

29. Scatter plot
• A Scatter plot cannot prove that one variable causes
another, but it does show how a pair of variables is
related and the strength of that relationship.
• Statistical tests quantify the degree of correlation
between the variables.
QUALITY TOOLS AND TECHNIQUES
7 tools of quality

30. Control charts
• Influence of special causes on process and out of
control situation
• Monitor processes to show how the process is
performing over time
• Following needs to be calculated.
– Mean variable
– Upper control limit (UCL)
– Lower Control limit (LCL)
• UCL and LCL can be calculated based on
• data from scientific literature
• Historical data
• Statistical data like Standard deviation
QUALITY TOOLS AND TECHNIQUES
7 tools of quality

31. Time between glucose measurements
(in Hours)
Day Hours
1/1/2017 5
1/2/2017 5.5
1/3/2017 5.5
1/4/2017 5
1/5/2017 7
1/6/2017 5
1/7/2017 5
1/8/2017 6
1/9/2017 6
1/10/2017 10
1/11/2017 11
Day Hours
1/12/2017 5
1/13/2017 6
1/14/2017 6
1/15/2017 5
1/16/2017 4.5
1/17/2017 5
1/18/2017 6
1/19/2017 5.5
1/20/2017 6
1/21/2017 5
1/22/2017 5
1/23/2017 5
QUALITY TOOLS AND TECHNIQUES
7 tools of quality

32. Time between glucose measurements
(in Hours)
Day Hours
1/1/2017 5
1/2/2017 5.5
1/3/2017 5.5
1/4/2017 5
1/5/2017 7
1/6/2017 5
1/7/2017 5
1/8/2017 6
1/9/2017 6
1/10/2017 10
1/11/2017 11
Day Hours
1/12/2017 5
1/13/2017 6
1/14/2017 6
1/15/2017 5
1/16/2017 4.5
1/17/2017 5
1/18/2017 6
1/19/2017 5.5
1/20/2017 6
1/21/2017 5
1/22/2017 5
1/23/2017 5
Calculate Mean and Standard deviation
Mean= 5.869565 SD = 1.575
QUALITY TOOLS AND TECHNIQUES
7 tools of quality

33. Time between glucose measurements
(in Hours)
Day Hours
1/1/2017 5
1/2/2017 5.5
1/3/2017 5.5
1/4/2017 5
1/5/2017 7
1/6/2017 5
1/7/2017 5
1/8/2017 6
1/9/2017 6
1/10/2017 10
1/11/2017 11
Day Hours
1/12/2017 5
1/13/2017 6
1/14/2017 6
1/15/2017 5
1/16/2017 4.5
1/17/2017 5
1/18/2017 6
1/19/2017 5.5
1/20/2017 6
1/21/2017 5
1/22/2017 5
1/23/2017 5
Calculate UCL (upper control limit)
and LCL (Lower control limit)
Mean= 5.869565
UCL = Mean + 3 *(Standard Deviation) = 10.59
LCL = Mean -3 *(Standard Deviation) = 1.14
QUALITY TOOLS AND TECHNIQUES
7 tools of quality

34. Time between glucose measurements
(in Hours)
Day Hours Mean UCL LCL
1/1/2017 5 5.869565 10.59 1.14
1/2/2017 5.5 5.869565 10.59 1.14
1/3/2017 5.5 5.869565 10.59 1.14
1/4/2017 5 5.869565 10.59 1.14
1/5/2017 7 5.869565 10.59 1.14
1/6/2017 5 5.869565 10.59 1.14
1/7/2017 5 5.869565 10.59 1.14
1/8/2017 6 5.869565 10.59 1.14
1/9/2017 6 5.869565 10.59 1.14
1/10/2017 10 5.869565 10.59 1.14
1/11/2017 11 5.869565 10.59 1.14
Day Hours Mean UCL LCL
1/12/2017 5 5.869565 10.59 1.14
1/13/2017 6 5.869565 10.59 1.14
1/14/2017 6 5.869565 10.59 1.14
1/15/2017 5 5.869565 10.59 1.14
1/16/2017 4.5 5.869565 10.59 1.14
1/17/2017 5 5.869565 10.59 1.14
1/18/2017 6 5.869565 10.59 1.14
1/19/2017 5.5 5.869565 10.59 1.14
1/20/2017 6 5.869565 10.59 1.14
1/21/2017 5 5.869565 10.59 1.14
1/22/2017 5 5.869565 10.59 1.14
1/23/2017 5 5.869565 10.59 1.14
QUALITY TOOLS AND TECHNIQUES
7 tools of quality

35. Control Chart
0
2
4
6
8
10
12
1-Jan-17
2-Jan-17
3-Jan-17
4-Jan-17
5-Jan-17
6-Jan-17
7-Jan-17
8-Jan-17
9-Jan-17
10-Jan-17
11-Jan-17
12-Jan-17
13-Jan-17
14-Jan-17
15-Jan-17
16-Jan-17
17-Jan-17
18-Jan-17
19-Jan-17
20-Jan-17
21-Jan-17
22-Jan-17
23-Jan-17
Timebetweenglucosemeasurements
(inHours)
Date
Hours Mean UCL LCL
In this case, the variation was detected on January 11 because the corresponding data point
was above the upper control limit. Root cause for the variations needs to be investigated.
QUALITY TOOLS AND TECHNIQUES
7 tools of quality

36. Control Chart
• Control charts are made with the existing data. Suggestions, if
necessary, are implemented based on the chart.
• Post Implementation, the mean and the control limits of the
control charts will vary depending on the effectiveness of the
implementation
• They are helpful for analyzing a process before and after an
improvement as well
• Helps to see how process mean and variability change as a
result of the improvement.
QUALITY TOOLS AND TECHNIQUES
7 tools of quality

37. Timetakenforadmittingthe
patient(inMinutes)
Days
Timetakenforadmittingthe
patient(inMinutes)
Days
Time taken for ICU admission
Time taken for ICU admission
QUALITY TOOLS AND TECHNIQUES
7 tools of quality

38. 160
180
200
220
240
260
280
300
320
2/9 3/9 4/6 5/4 6/1 6/29
Week
EDStay(minutes)
Reducing Delays for Patients Admitted to the
Emergency Department
Goal
QUALITY TOOLS AND TECHNIQUES
7 tools of quality

39. Work
Days
ACA
Initiative
begun
Optimize
the Team
0
10
20
30
40
50
60
70
80
90
100 'Oct01
'Jan02
'Apr02
'Jul02
'Oct02
'Jan03
'Apr03
'Jul03
'Oct03
'Jan04
'Apr04
'Jul04
'Oct04
'Jan05
'Apr05
'July05
'Oct05
'Jan06
'April06
'July06
SI
Initiative Optimize
the Team
Imaging – MRI Backlog
7 tools of quality

40. Flow Chart
• Process flow chart of flow diagram
• A powerful improvement tool to define, describe, and
communicate clinical, administrative and operational
processes.
• A flowchart represents an algorithm or process with
the help of pictorial symbols.
• They trace the steps the “object” of the process goes
through from start to finish. (a lab test, a clinic visit, a
specialty visit, an imaging study, etc. )
• Boxes of pictorial symbols connecting with arrows to
represent sequence of activities.
• Flowcharts help in identifying points or bottle necks
where problems might occur.
QUALITY TOOLS AND TECHNIQUES
7 tools of quality

41. • Develop understanding of how a process is done.
• Study a process for improvement.
• Communicate to others how a process is done.
• When better communication is needed between
people involved with the same process.
• In order to document a process.
• While planning a project.
When is it used?
QUALITY TOOLS AND TECHNIQUES
7 tools of quality

42. Flow chart- Symbols
One step in the
process
Direction of
flow
Link to another
page or
flowchart
Input or output Document Start and end
points
Decision based
on a question
Delay or wait
7 tools of quality

43. The Process Flow Diagram (Flow Chart)
Used to understand the
current process and identify
opportunities for
improvement. It shows the
work flow through the process
including all activities,
decisions, delays, and
measurement points.
DELAY
DELAY
ACTIVITY
ACTIVITYDECISION
ACTIVITY
DECISION
ACTIVITY
BEGIN
END
YES
ACTIVITYNO
NO
YES
QUALITY TOOLS AND TECHNIQUES
7 tools of quality

44. Flow chart
QUALITY TOOLS AND TECHNIQUES
7 tools of quality

45. Check Sheet
• Defect concentration diagram
• A check sheet is a structured, prepared form
for collecting and analyzing data. This is a
generic tool that can be adapted for a wide
variety of purposes
• A simple document used for collecting data in
real time and at the location where the data is
generated.
QUALITY TOOLS AND TECHNIQUES
7 tools of quality

46. When is it used?
• When data can be observed and collected
repeatedly by the same person or at the same
location.
• When collecting data on the frequency or
patterns of events, problems, defects, defect
location, defect causes, etc.
• When collecting data from a production
process.
QUALITY TOOLS AND TECHNIQUES
7 tools of quality

47. Check sheet
Wrong
admission
Wrong
diet
Late
Discharges
Staff not
punctual
for duty
Missing
CSSD item
Problems identified in the Wards
7 tools of quality

48. 7 tools of quality