Root Cause Analysis

Root Cause Analysis

Root cause analysis is an approach for identifying the underlying causes of why an incident occurred so that the most effective solutions can be identified and implemented.  It's typically used when something goes badly, but can also be used when something goes well.  Within an organization, problem solving, incident investigation and root cause analysis are all fundamentally connected by three basic questions:  What's the problem? Why did it happen? and What will be done to prevent it?

The Cause Mapping method of Root Cause Analysis

In the Cause Mapping method, the word root, in root cause analysis refers to the causes that are beneath the surface. Most organizations mistakenly use the term "root cause" to identify the one, main cause. Focusing on a single cause can limit the solutions set resulting in better solutions being missed. A Cause Map provides a simple visual explanation of all the causes that were required to produce the incident. The root is the system of causes that reveals all of the different options for solutions.

There are three basic steps to the Cause Mapping method:
  1. Define the issue by its impact to overall goals
  2. Analyze the causes in a visual map
  3. Prevent or mitigate any negative impact to the goals by selecting the most effective solutions.

For more information about our Cause Mapping workshops click here.


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What is a Cause Map?

A Cause Map provides a visual explanation of why an incident occurred.  It connects individual cause-and-effect relationships to reveal the system of causes within an issue.  A Cause Map can be very basic and it can be extremely detailed depending on the issue.

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How to read a Cause Map

Start on the left. Read to the right saying "was caused by" in place of the arrows.  Investigating a problem begins with the problem and then backs into the causes by asking Why questions.

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The questions begin, "Why did this effect happen?"  The response to this question provides a cause (or causes), which is written down to the right. 

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The next question is again, "Why did this effect happen?" The cause that was written down last becomes the effect for the next Why question. Anyone who's ever had a three-year-old in their life will immediately recognize how Why questions change a cause into an effect. This is fundamentally how causes and effects link together to create a chain of events. Writing down 5-Whys, shown below, is a great way to start an investigation because it's so simple.


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In the Cause Mapping method, a problem within an organization is defined by the deviation from the ideal state.  A Cause Map always begins with this deviation which is captured as the impact to the organizations overall goals.


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In addition to the standard Why questions, which tend to create linear cause-and-effect relationships, the Cause Mapping method also asks "What was required to produce this effect?" Anything that is required to produce an effect is a cause of that effect. This question, "What was required?," builds a detailed Cause Map that provides a more complete representation of the actual issue.

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Why does the Cause Map read Left to Right?

It should be noted that the popular fishbone cause-and-effect diagram starts with the problem on the right and builds the causes to the left. It was created by Kaoru Ishikawa (1915-1989) in Japan. The fishbone diagram builds from right to left because the Japanese language reads from right to left. The Cause Mapping method actually uses Ishikawa's convention by asking Why questions in the direction we read.


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The fishbone is widely recognized as one of the standard quality tools.  Ishikawa was a pioneer with his approach.  The fishbone cause-and-effect diagram is part of every six-sigma program.  A Cause Map builds on the original lessons with the fishbone with some subtle, but important distinctions.  A fishbone starts with just one, single problem which doesn't reflect the nature of real world issues.  It reads right to left because the Japanese language reads that direction.  It mixes causes and possible causes without specifying evidence.  And, it breaks apart the fundamental cause-and-effect relationships within an issue by grouping the causes into general categories.

   

5-Whys on a Cause Map

The 5-Why approach is an excellent example of basic cause-and-effect analysis. Just as a journey of a thousand miles begins with the first step; every investigation, regardless of size, begins with one Why question. The Why questions then continue, passing through five, until enough Why questions have been asked (and answered) to sufficiently explain the incident. The 5-Why approach, created by Sakichi Toyoda (1867 - 1930), the founder of Toyota, is a simple way to begin any investigation. A Cause Map can start with just 1-Why and then expand to accommodate as many Why questions as necessary. Some refer to the Cause Mapping method as "5-Whys on Steroids."

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Problems within an organization are typically not singular.  In the real world, a problem typically impacts more than one goal.  The Cause Map starts with the impact to the goals even if more than one goal is impacted.  If the causes are all part of one incident then the causes and the goals will all be connected on one Cause Map.


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Some causes are linked with AND In between

ANDs show where more than one cause is required. When an effect has more than one cause, both causes are placed on the Cause Map. Each cause is connected to the effect with an AND placed inbetween. These causes are independent of each other, but they are both required to produce that effect. An AND is needed when people provide different, yet valid, explanations of a cause. People think of cause-and-effect as a simple one-to-one relationship; an effect has a cause. In reality, every effect has causes.


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Think Reliability :: Root Cause Analysis
Cause Mapping I - Effective Root Cause Analysis Workshop Training
      
September 18-18, 2014
     ASSE New Mexico Chapter Conference
Cause Mapping II Root Cause Analysis Facilitation and Documentation Workshop Training
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