It is often tempting to see the immediate symptoms of a problem and FIX things so that these symptoms disappear only to see different symptoms appear later for a related problem.

To successfully solve problems, we must get to the root cause of the problem; so-called Root Cause Analysis (RCA).

The following are popular techniques used to carry out RCA:

• Brainstorming

Brainstorming the RCA relies on SEVERAL people producing their thoughts and feeding off other people’s thoughts in order to converge on the probable root cause of the problem.

It is a relatively unstructured technique for RCA and it can be difficult to see the root cause amongst a great deal of data.

• The 5 Whys

The 5-Whys technique is possibly the simplest RCA technique; it is a little like an annoying 5-year old asking question after question to the answers you give them.  Essentially, the RCA workshop facilitator keeps asking “why” until an apparent problem root cause is discovered.

Generally, a minimum of 5 ‘Why?’ questions are asked, although sometimes more or less may be needed.  For example:

• Problem - the vehicle will not start
  • Why? - The battery is dead
  • Why? - The alternator is not functioning
  • Why? -  The alternator belt has broken
  • Why? -  The alternator belt was well beyond its useful service life and not replaced
  • Why? - The vehicle was not maintained according to the recommended service schedule

This example could be extended to discover why the vehicle had not been maintained properly; the root cause could be that the need for regular servicing was unknown; the questions go on until the group agree that a fixable cause has been found.

• Flowcharting

Flowcharting can help discover problems about a process in a graphical manner; a group of people affected by the problem will chart the supposed ‘As-Is’ process to see where the problem has arisen:

• SOMEONE does not know that they have responsibilities in the process
• A vital step in the process has been left out or is not being ‘run’
• A step in the process is producing incorrect output
• Fishbone Diagrams

A Fishbone or Ishikawa Diagram is most useful when the “5 Whys” technique is considered to be too basic. In a Fishbone Diagram, the various causes are grouped into categories, with arrows in the image indicating how the causes flow toward the problem; categories used in the diagram are not pre-defined but common categories include equipment, processes or methods, measurements, materials, environment and people.

This TYPE of RCA seeks to understand the possible causes by asking questions such as “what actually happened,” “when,” “where,” “why,” “how,” and “so what” until a possible cause is identified and the consequences and significance is investigated further for each category; for example:

• Affinity diagrams

An Affinity Diagram is a tool that gathers LARGE amounts of language data (ideas, opinions, issues) and organizes them into groupings based on their natural relationships.  The Affinity process is often used to group ideas generated by Brainstorming.

See Affinity Diagram for more information