Root Cause Analysis
A Root Cause Analysis may be performed when a failure has been experienced or a symptom is exhibited that needs attention and analysis to resolve. This can also be done as a form of detailed retrospective that is looking to uncover upstream causes that need to be remedied.
One simple technique is to work with a team or group of interested participants and facilitate a group discussion using a whiteboard or similar to illustrate the cause and effect landscape.
Initially start with the symptom or failure that has been observed and place this in the bottom right hand corner of the board as the resulting effect from the upstream causes.
And Then?
Next work backwards and draw a couple of arrows that finish at the symptom and ask the team what are the contributing factors (causes) of the symptom, and draw them on the board so that they are now connected to the symptom as first order causes.
And Then ... And Then?
Next repeat the process of drawing a couple of arrows going into the first order causes and ask the team what are the contributing factors (causes) of the first order causes, and draw them on the board so that they connect to the first order causes, and now labelled as second order causes.
It is not uncommon for teams to not necessarily think beyond the immediate causes of a symptom and so as a facilitator it may take a bit of encouragement to enable the team to think beyond the first order causes and gain deeper insights.
And Then ... And Then ... And Then?
Rinse and repeat the approach until the team are unable to identify any further causes. (It is unusual to go beyond fifth order causes, as this is normally enough to indicate a remedy.)
The result should be a cause and effect map that relates higher order causes to the resulting symptom.
Closure
The last stage is to ask the team for potential remedies that can be applied to the higher level causes and place these on the diagram as well, preferably in a different colour. At this stage an action plan can be drawn up to implement the remedies and resolve the underlying causes that resulted in the symptom.
The 5 Whys
For further information, check out The 5 Whys originally championed by Taichi Ohno at Toyota from which the method above is derived.
Also have a look at the Current Reality Tree by Eliyahu Goldratt which has an approach to map the causes and effects and their relationships
See Also
References
- Toyota Product System: Beyond Large Scale Production, Taiichi Ohno, 1988