Cause and effect diagrams, also known as fishbone diagrams or Ishikawa diagrams, can be used to analyze problems and identify improvement possibilities. They show a central problem or effect and branch out to display potential contributing causes categorized under main headings like Man, Machine, Method, Materials, Measurement, and Environment. Turning the diagram around allows the tool to also conduct an impact analysis of potential solutions by examining what effects implementing a solution may have on the original cause factors.

1. Tool D8Cause and effect diagrams
Cause and effect diagrams are effective tools for analysing problems
and identifying improvement possibilities. Turned around, they are
equally effective tools for the a priori impact analysis of solutions.
The usual cause and effect diagram is also named fishbone diagram
owing to its form, or Ishikawa diagram referring to its inventor, the
Japanese quality mana
used in quality manage-
ment and continuous im-
provement.
Starting from
gement expert Kaoru Ishikawa. It is frequently
a defined
roblem, i.e. the effect
-
ses
re:
ntext: Man, Machine, Method, Materials, Measurement, Envi-
d
ople, Equipment,
adings
ake sure that you start drawing the basic fishbone structure big
r
p
of origin, major causes
are identified. Then for
each of these causes sub
causes are identified on
up to three levels.
Frequently used cau
a
• in a manufacturing
co
ronment. Environment includes the organisational environment.
Where the environment is only organisational, it may be replace
by Management;
• an alternative version for manufacturing is Pe
Process/es, Materials, Policies, Procedures/Products;
• in an organisational change context, the same cause he
can be used if applicable. But it is definitely recommendable to
insert Management (man-made environment) and (natural) envi-
ronment as separate influence factors.
M
enough so as to be able to go into much detail where needed. As
there is a well-established software for this type of analysis called
XMind, some facilitators may prefer to use a laptop and projector fo
collectively analysing a problem.
Fishbone diagram
21.07.2008, 11:50:12

2. 2/2
Once a solution to the problem is identified it might make sense to
do the analysis the other way round. Starting from the solution
found as the cause, you ask yourself which effects the implementa-
tion of this solution might produce on the formerly used cause fac-
tors. This impact analysis helps you to plan the implementation
process and to identify possible effects or side effects you want to
avoid. You then would try to improve your solution or implementa-
tion strategy.
Impact analysis