THE 7 BASIC QUALITY TOOLS Susan Batchilder January 24, 2013.

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THE 7 BASIC QUALITY TOOLS

Susan BatchilderSusan BatchilderJanuary 24, 2013January 24, 2013

Group Activity:WHAT’S IN YOUR TOOL BOX?

• What is the purpose of your personal toolbox?– cleaning, fixing, remembering, coaching,

etc…

• What’s in your personal tool box?

• When did you last use your tool box?

• Do you have a tool box for your job?

• What is the purpose of your tool box for work?

QUALITY TOOLS• Purpose: provide the means for making

decisions.• No particular tool is mandatory, any one

may be helpful, depending on the circumstances.

• 95% of a company’s problems can be solved using these tools.

• These are basic tools designed for simplicity.• Only one requires any significant training.

Question: What tools do YOU use for making decisions in YOUR job?

7 BASIC QUALITY TOOLS

• FLOW CHART• CAUSE AND EFFECT DIAGRAMS• CHECK SHEET • HISTOGRAMS• PARETO CHART• SCATTER DIAGRAM• CONTROL CHARTS

Question: Why do we use these tools?

QUALITY TOOLS CAN…

• Help to identify and prioritize problems quickly and more effectively

• Assist with the decision making process• Simple but powerful tools for use in

continuous improvement activity• Provide a vehicle for communicating

problems and resolutions through-out the business

• Provide a way of extracting information from data collected.

A Side Topic

STRATIFICATION• The 7 Quality Tools are useful when collecting data of

daily activities and analyzing them to detect and solve problems, and an important concept for data analysis is STRATIFICATION.

• Stratification mean classification of data in to a couple of layers, and each layer is a subset of the population.

• Through stratification different statuses from the same data is retrieved.

• What layers are considered for data analysis is crucial when identifying problems.

Example of Stratification• Number of births per year• Number of births by gender per year• Number of births by mom’s economic status by

gender per year

• deliveries per week• deliveries per day of the week per week• deliveries by hour per day of week per week

• DANAGER: When using stratification ensure it is value added

• Back to the 7 Quality Tools

FLOW CHARTS• Purpose: Illustrates the steps in a process• Uses:

– Analyzing a process (e.g. relating one setp in the process to others)

– Initiate process improvements (e.g. non-value added steps)

– Indicates where in the process to take measurements and collect data

• DANGER: including assumed or desired steps

• Note: The utility of the chart will correlate directly to its accuracy.

Example: Flow Chart

CAUSE AND EFFECT DIAGRAMS• Purpose: to identify as

many possible factors for an effect or problem and sort the causes into useful categories.

• When to use?– Identifying possible

factors– When team’s thinking

falls into a “rut”

• Fishbone (most common)– Generic categories:

Methods, Machines, Materials, Manpower, Measurement, Mother Nature

HOW TO CREATE A FISHBONE CAUSE AND EFFECT DIAGRAM

Problem Statement“Effect”

Methods

Mother Nature Measurement Materials

Manpower Machines

Management

Maintenance

CAUSE AND EFFECT DIAGRAMS• Other fishbone categories:

– Plan, Policies, Procedures, Plant, People– Customers, Suppliers, Shipping, Warehouse…

• 5 WHYS: a method for getting to the root cause. – Can also be used during the construction of the

fishbone diagram.

• GROUP ACTIVITY TIME – Let determine the cause of a particular problem. Please give me a problem statement and we’ll use the 6M’s.

GROUP ACTIVITY TIME

Problem Statement“Effect”

Methods

Mother Nature Measurement Materials

Manpower Machines

CAUSE AND EFFECT DIAGRAMSNow What?

• Categorize (e.g. not probable, probable, very

probable)• Regression analysis (requires in-depth training)• Design of experiments (requires in-depth

training)• Lets go back to our example and

determine what our next steps will be.• Do you remember the first time

you heard about a check list with regards to data collection?

Example of a Check List

CHECK SHEET• WHAT: A structured and prepared form.• PURPOSE: To collect and analyze data so

decisions can be based on facts• WHEN:

– When data can be observed and collected by the same person or at the same location.

– When collecting data on the frequency or pattern of events, problems, defects, defect location, defect causes, etc.

– When collecting data from a production process.

• Data can further be used to create a histogram, bar chart and Pareto chart

A Check List Can Become …

A Bar Graph

HISTOGRAM• WHAT: A frequency distribution bar graph• USES:

– Illustrates how often each different value in a data set occurs

– Allows us to make sense of data– Allows use to see patterns that are difficult to see in

tables of numbers

• DANGER: Before making any conclusions from a histogram, it must be confirmed the process was operating normally during the time period being studied

Language of HistogramsWhat do they tell us?

SCATTER DIAGRAM

• WHAT: Scatter diagram graphs PAIRS of numerical data.

• PURPOSE: To look for a possible relationship

• DANGER: Even if the scatter diagram shows a relationship, do not assume one variable causes the other. Both variable may be influenced by a third.

Scatter Diagram Examples

Graph 1 – strong correlation (linear)

Graph 2 – moderate correlation

Graph 3 – no correlation

Also – quadratic, exponential, sinusoidal, and others

PARETO CHART• What: Bar graph organized with the longest bars on

the left and the shortest to the right• Purpose: Problem identification tool --- Visually

depicts which issues are more significant• Use when…

– Analyzing data about the frequency of problems/causes in a process

– There are many problems/causes and there is a need to focus on the most significant

– Analyzing broad causes by looking at their specific components

– Communicating data to others

PARETO PRINCIPLE

20/80 RULE• THE IDEA THAT 20% OF THE CAUSES

GENERATES 80% OF THE RESULTS

With the Pareto chart we are identifying the “vital few” from the “trivial many”.

PARETO CHART EXAMPLE

CONTROL CHARTS• What: A statistical graphical

representation used to study how a process changes over time

• Purpose: To distinguish between variation in a process resulting from common causes, and variation resulting from special causes.

• Data are plotted in time order.• Graphs include a central average line,

a upper control limit line and a lower control limit line determined from historical data.

“Out of Control”

Types of Control Charts• Variable (continuous data – measureable)

• X-bar Chart (average)• R chart (range)• s chart (deviation)• X chart (single data point – individual)• Moving range chart • XmR (individual with moving range)

• Attribute (discrete data – count)• p chart (percentage of defective units)• np chart (number of defective units)• c chart (number of defects per unit)• u chart (average number of defects per unit)

WHICH CONTROL CHART DO I USE?

OTHER TOOLS

• 5 WHYs (previously mentioned)• Brainstorming• Time Line• Fault Tree Analysis• Process Analysis

5 WHY’S – an example• Problem --- Why is memorial A

deteriorating faster than the other memorials?– Why? –washed more frequently– Why? –more bird droppings– Why? –birds attracted to monument– Why? –more fat spiders around it– Why? –more tiny insects during evening hours– Why? –illumination attracts more insect– Solution

• Illuminate an hour later in evening

5 WHYs

PROBLEMPROBLEM

ROOT CAUSEROOT CAUSE

WHY?WHY?

WHY?WHY?

WHY?WHY?

WHY?WHY?

WHY?WHY?

ProcessProcess Best Practice

PROBLEM

WHY?

WHY? WHY?

WHY?

WHY?

WHY? WHY?

WHY? WHY?

MULTIPLE POTENTIAL ROOT CAUSES

WHY?

WHY?

WHY?

BRAINSTORMING

Brainstorming• Can be performed by an individual or a

group

• Classic Example – write down anything that comes to mind

• Ask questions – 5 Whys

• Categorize – Fishbone

• Many others

TIME LINE

• A presentation of a chronological sequence of events along a drawn line that enables the reader to quickly understand relationships relating to, or limited by, time

• Lines are usually drawn from left to right or top to bottom

• Example --- murder mysteries, time line of events before and up to the time of death

FAULT TREE ANALYSIS (FTA)• WHAT

– A graphicgraphic representation of the major faults or critical major faults or critical failuresfailures associated with a product, the causescauses for the faults, and potential potential countermeasures.countermeasures.

• WHY– It helps to identify

areas of concern for new product design or for improvements of existing products.

– It helps to identify corrective actions to correct or mitigate problems.

FAULT TREE

FTA – When to use?

• Designing new products/services

• Dealing with identified problems in existing products/services

• To optimize process features and goals

• To design for critical factors and human error

• To help identify root causes of trouble

• To design remedies and countermeasures

FAULT TREE

PROCESS ANALYSIS

• An operation (e.g. business) is composed of processes designed to add value by transforming inputs into useful outputs. Processes can have a significant impact on the performance of a business and process improvements can improve competitiveness.

• A process analysis is performed when the process (as a whole or as a part) needs to be better understood.

Process Analysis• Processes are analyzed

to better understand their:– Activities– Relationships– Values of relevant

metrics

• Process analysis generally involves the following tasks:

• Defining process boundaries (input/output)

• Process flow diagram• Determining capacity of

each step of process• Identifying limiting

step(s)• Using analysis to make

business decisions and improvements

Process Analysis – Performance Measurements -

• Process Capacity• Capacity Utilization• Throughput rate• Throughput time• Process time

• Idle time• Work In Process • Set-up time• Direct Labour Content• Direct Labour Utilization

DANGER WIL ROBINSON!

WHY DO TECHNIQUES FAIL?

• Problem solvers might question themselves– Am I using the tool correctly?

• Is there a misconception in using the tools to find the root cause of problems?

• Is there another technique to help me go beyond the basic cause and effect analysis and get better results when investigating issues?

COMMON “DANGERS”

• Only tool• Confirmation Bias• Unable to go beyond current

knowledge• Human Factors• Single Cause

COMMON “DANGERS” – Only Tool -

• Many believe cause and effect analysis is the only, or preferred method to find root causes

• Avoid this misconception• You CAN modify approaches, and use

other tools alone or in combination

COMMON “DANGERS”- Confirmation Bias -

• People hypothesize a familiar pattern (answer), and tend to look for information to confirm their conclusion (bias).

• People tend to jump to conclusions before all the data is collected and analyzed

• People may subconsciously disregard evidence that counters their conclusion – or requires more resources to investigate.

COMMON “DANAGERS”

- Current Knowledge -

• Sometimes it is difficult for people to analyze problems beyond their current knowledge and try to make the problem fit inside their understanding of the issue.

• Problem solvers must have knowledge of all possible causes to be able to reach an accurate conclusion.

COMMON “DANGERS”- Human Factors -

• Generally human performance causes most problems, but most problem solvers have no formal training in the science of human error and human performance.– Lack of…

• Communication, Knowledge, Teamwork, Resources, Assertiveness, and Lack of Awareness,

– Also…• Complacency, Distraction, Fatigue, Pressure, Stress,

and Norms

• Cookie Cutter Approach – Tendency to play the blame game– Blame it on either human error or lack of training or

insufficient training

COMMON “DANGERS”- Single Cause -

• Root cause analysis stops once a single cause is found

• Just like accidents, major problems are usually the result of a sequence of events containing multiple causal factors.

• Single causal chain misconception leads to missed opportunities to improve performance

COMMON “DANGERS”- Others -

• Improper use of deductive reasoning• Lack of practical training / opportunity to

use• Difficulty in trending results• Tunnel vision• Fuzzy haze

– When the brain automatically fills in the missing information when is perceives something, sometimes leading to misperceptions

• Results not repeatable– Results vary based on the analysis

- What would you do differently? -• Problem --- Why is memorial A deteriorating

fasters than the other memorials?– Why? –washed more frequently– Why? –more bird droppings– Why? –birds attracted to monument– Why? –more fat spiders around it– Why? –more tiny insects during evening hours– Why? –illumination attracts more insect– Solution

• Illuminate an hour later in evening

COMMON “DANGERS”- Deteriorating Monument -

• There are many possible factors, and our list presents a few possibilities to demonstrate what could be missed without fully understanding the sequence of events before drawing conclusions.

• Missing potential alternative can waste efforts when fixing phantom problems or pushing problems from one area to another.

COMMON “DANGERS”- Deteriorating Monument -

• SOMETHING TO PONDER…– The solution of turning the lights on one

hour later in the evening reduced deterioration by 90%

• BUT REMEMBER…– Correlation does NOT

prove causation

COMMON “DANGERS”- Deteriorating Monument -

• Was reduction really due to change in lighting schedule or were there other factors not accounted for…– Aware of deterioration, cleaners were

more careful?– Did a weather change shift insect

behaviour?– Are deterioration measurements accurate?– Did lighting change shift problem to

another monument?

FOR YOUR INFORMATION

FYI7 NEW QUALITY TOOLS for…

• Innovating• Communicating• Planning

• Tools– Affinity diagrams (for brain storming)– Arrow diagrams (can be simple or used with CPM & PERT)– Matrix data analysis – Matrix diagrams– Program decision program charts – Relationship diagrams– Tree diagrams

FYI: QMS MATURITY LEVELS AND QUALITY TOOLS

• Maturity Level: – Low

• Most Useful Tools:– Seven basic tools– Audits– Cost of quality (COQ)– Statistical process

control (SPC)

• Description:– There is no formal quality

system, or if one exists, it is not practiced on a daily basis. Customer complaints and other external failure costs are high. The quality dept is held responsible for quality. There is little or no formal continuous improvement that involves people who actually carry out the work processes.

FYI: QMS MATURITY LEVELS AND QUALITY TOOLS

• Maturity Level: – Medium

• Most Useful Tools:– Creativity tools– Customer surveys– Failure mode and

effects analysis (FMEA)

– Benchmarking– Design of

experiments (DOE)

• Description:– External failure costs

have been lowered, but these is still a high rate of internal failures. Each dept accepts it role in the quality management system, and improvement projects involving employees are frequent.

FYI: QMS MATURITY LEVELS AND QUALITY TOOLS

• Maturity Level: – High

• Most Useful Tools:– Seven management

tools– Employee surveys– Quality function

deployment

• Description:– Management systems

for areas such as quality, safety, environment and finance are seamlessly integrated and driven by the organizational strategy. All depts and work processes monitor their own performances and implement daily improvement aligned with strategic direction.

POP QUIZ EVERYONE

QUALITY TOOLBOX SUMMARYThe 7 Quality Tools are…

QUALITY TOOLBOX SUMMARY

• These are TOOLS, and not the only tools

• They can be used alone or in combination

• They can be used by the individual and groups

• Generally, they do not require mastership to be used

• And remember to “Document” them – photos work great

7 QUALITY TOOLS

QUESTIONS?

Disclaimer: All of the information provided in this presentation was obtained from various internet webpages.

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