This document provides an overview of a cause and effects diagram, also known as a fishbone diagram, which is a visual tool used in problem solving. The fishbone diagram displays possible root causes of a problem categorized into branches. It is used in early problem solving stages to brainstorm potential causes. The document outlines the basic steps to construct a fishbone diagram, which involves drawing the backbone and branches, labeling the branches, listing the problem, and identifying factors within each branch that may be causing the problem. Completed diagrams can then be evaluated to eliminate irrelevant causes and focus on the most likely causes to address.

1. Cause & Effects Diagram
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1 2 Fishbone Diagram
Measure Machinery Manpower
3 Problem Statement
Problem
Issue Manpower
Person is late to work
Mother Methods Materials 12% of days worked,
Nature mainly occurs Monday.
4 Possible Causes Materials
Machinery
For clarity: one branch shown.
Vehicle won’t
Start on cold days Badge Reader
causes huge backlog
Complete Cause and Effect
Measure Machinery Manpower
Vehicle won’t
start on cold days Badge Reader causes
huge backlog
I’m not sure what I like to have a
leisurely breakfast.
time I leave the house
Carpool passengers
Problem Issue
are not ready on time.
Person is late to work
12% of days worked,
mainly occurs
I follow the same
I usually can’t recall where Monday
I put the car keys.
route everyday.
My morning routine
makes me run late
Someone moves my
Fog slows down I get gas on Tuesday badge overnight.
Walk the dogs
Iron a shirt
my commute on the way in.
Snow slows
my commute
Mother Methods Materials
Nature
One Page Primer Series
Tony Webster
Lean Sigma Professional
www.linkedin.cominwebstert

2. Cause & Effects Diagram
V1.0 07.26.09
What is it? Who Should Use It?
Anyone who wants to improve their
A visual snapshot of the collected
value to their organization should learn
knowledge of possible root causes;
and become proficient at problem
displayed using categories.
solving methods.
Why Use It?
• Drives focus on causes, not symptoms.
• Enables teams to focus on the problem
at hand – not the history of the
problem, or interpersonal dynamics. When Do I Use It?
Fishbone diagrams are a simple tool that
are used in early problem solving stages
to brainstorm or review a list of possible
root causes.
Step Description
1 Draw the backbone and main branches.
2 Label the main branches of the fish with categories which will guide the process of generating possible root
causes. (Use 6M’s or 5P’s on to label the branches.)
3 List the problem or issue to be investigated in the “head” of the fish.
4 Identify the factors within each category that may be affecting the problem/issue. The team should ask...
"What are the <category> issues affecting/causing... <problem>
Using a Completed Cause & Effect Diagram
5 Evaluate the fishbone to eliminate irrelevant or out of scope causes with respect to the problem statement.
(ex. Fog is listed as a factor – but mostly likely does not occur mostly on Mondays)
6 Evaluate the remaining possible causes to establish consensus on factors that are the “most likely causes” .
7 Rank the most likely causes for impact on the problem, then develop and implement corrective actions for
them in order of priority.