A much more effective way of preventing future issues is adopting the root cause analysis method that strives to identify the root cause of problems and solve them instead of working on individual symptoms that might arise again.

What Is Actually a Root Cause?

A root cause is an underlying cause. Problems appear when we have variations of usual systems or procedures, so in order to solve those problems, we look for the causes. As I was saying before, we could just look for the first cause that comes to mind, or train our teams to conduct a thorough analysis every time we have an issue to make sure we always solve it right the first time.

Edwards Deming, as statistician, also liked to say that there were two main kinds of causes - common and special.

What is Root Cause Analysis?

RCA, or root cause analysis, refers to the systematic process of identifying underlying causes of problems and determining suitable solutions. RCA uses a range of principles, techniques, and methodologies to uncover the root causes of a trend or event. By going beyond surface-level cause and effect, RCA allows for identifying any process or system failures that are the main cause of the issue.

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History of Root Cause Analysis

Root cause analysis can be linked to the broader discipline of total quality management, which has evolved to incorporate several approaches to problem-solving, problem analysis, and root cause analysis. 

Root cause analysis is essential to the broader problem-solving process, making it crucial for an organization's continuous improvement. It is best to see RCA as a part of a larger problem-solving effort than a standalone solution to problems since it may not produce results on its own. 

Core Principles

For effective root cause analysis, some core principles are used as guidance. They help with quality analysis and gain stakeholders' and clients' trust and support.

  • Research the 'whys' and 'hows' of a problem instead of blaming 'who' caused it.
  • Resolving symptoms may be significant as it helps with short-term relief.
  • The main effort should be on understanding and correcting the root cause.
  • There could be multiple root causes.
  • Gather adequate information to guide corrective action.
  • Prevention of the root cause is essential for the future.
  • A systematic approach helps find solid evidence to support root cause claims.

Benefits and Goals of Root Cause Analysis

The main goals of root cause analysis are:

  • Discovering the root cause of a problem
  • Determining methods to resolve it while learning from underlying issues.
  • Applying the learnings to prevent future recurrence of the issue by modifying the core process. 

By conducting a thorough RCA, you can ensure repeated success.

Types of Root Causes Analysis

Common or Environmental Causes:

These tend to cover 85% of the cases. They’re called common because they equally affect all workers in a section. Poor light, humidity, vibration, poor quality cafeteria food, absence of a proper quality program, poor supervision or instruction, problematic procedures, mismatch between requirements and deliverables, poor arrangements for the comfort of workers, are all examples of common or environmental causes.

These are faults in the system, so they usually persist until they are addressed by management. Employees cannot change the lighting or write new contracts for raw material or call for action at a high level.

Special or Local Causes:

These (the other 15%) are specific to a local condition. In many cases, they can be corrected on a statistical signal by the employees themselves. Signals tell an employee whether to leave the process as it is or to take action.

Common causes are more difficult to identify than special causes. When all special causes have been removed, common causes remain. Once a common cause is identified, management must decide whether it will be economically feasible to change it. Management’s obligation is to focus attention on the common causes of variability, but in many companies, employees are the first to be blamed when only 15% of it is their responsibility to resolve!

So if we really want to get rid of issues with quality, the art of root cause analysis should be managed accordingly to be able to identify the real root causes, and determine if they are common (to be fixed by management) or special (to be fixed by employees). If you are a Six Sigma practitioner, you would do this in the analyze phase of your DMAIC process.

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Approaches to Root Cause Analysis

There are several techniques and methodologies that can be used for root cause analysis, including,

  1. Change analysis: Suitable where the system's performance has significantly changed. It examines modifications in personnel, equipment, information, and other factors that may have contributed to the performance shift.
  2. Events and causal factor analysis: Commonly used for single-event issues. The process quickly collects evidence to establish a timeline of events leading up to the accident, after which the cause and contributing factors are identified.
  3. Barrier analysis: This approach concentrates on determining the controls that were a part of the process which failed to prevent or detect problems.
  4. Management oversight and risk tree analysis: This technique employs a tree diagram to examine what occurred and why it may have happened.
  5. Kepner-Tregoe Problem Solving and Decision Making: This model consists of four distinct phases for resolving problems
  • Analyzing the situation 
  • Analyzing the problem
  • Analyzing the solution 
  • Analyzing any potential problem

Techniques and Methods to Conduct an Effective Root Cause Analysis:

Below are some of the most commonly used techniques of root cause analysis. 

5 Whys

The 5 Whys approach asks a 'WHY' question and, for every answer, follows it up with another 'WHY' to dig deeper into the problem. It usually takes 5 'whys' to reach the root cause, but the number could extend even more. This technique is a great way to reach a clearer, more defined, and detailed answer which can then be resolved to fix the issue.

Change Analysis/Event Analysis

A valuable technique to identify multiple potential causes, change analysis thoroughly evaluates the changes that lead up to an event to explore the root cause. It analyses the history of the event to identify where something went wrong. There are some steps to this technique.

  1. List every potential cause that leads to the event, including every time a change occurred for better or worse.
  2. Categorize every change depending on the amount of influence you had on it. For example, owned or unowned, internal or external, and so on. 
  3. Analyse event by event and continue categorizing each event as - an unrelated factor, a contributing factor, a correlated factor, or a potential root cause. It is a critical phase where you can incorporate other RCA techniques, such as 5 whys. 
  4. Evaluate how you can remedy or replicate the root cause. 

Cause and Effect Fishbone Diagram

A fishbone diagram visually depicts the cause-and-effect relationships. It identifies potential causes for a problem by following categorical branched paths until you arrive at the most probable cause. 

  1. The diagram starts in the middle, or the fish's spine, which is the problem. 
  2. Come up with numerous categories of causes that make up the rib bones of the fish, with each category creating an off-shooting branch from the spine. 
  3. The categories could be broad and, after grouping, can be broken down into smaller sections. For example, 'people' can lead to potential root causes like 'leadership', 'training', and more. 
  4. By questioning each branch and delving deeper into potential causes and sub-causes, you can get closer to the root of the problem. 

This methodology eliminates unrelated categories and recognizes correlated factors and probable root causes. 

Tips for Performing Effective Root Cause Analysis

Asking questions is crucial to root cause analysis, as it helps clarify information. Further evaluation can help you understand 'why' it was the root cause, 'what' it means, and 'how' to prevent the issue. 

Work With a Team and Get Fresh Eyes

Using a team or even a partner will help you discover the solution faster. It will also check any biases and offer an additional point of view. 

Plan for Future Root Cause Analysis

Whenever you perform RCA, pay attention to the process to determine whether a certain method works better for your business.

Remember to Perform Root Cause Analysis for Success Too

You can also use RCA to assess the root cause of success. It helps protect and prioritize the main elements that could prevent potential problems from arising while guaranteeing overall success. 

Interested to get skilled in the six sigma methodologies? Check out the Lean Six Sigma Green Belt Certification Training Online. Enroll now!


RCA is an excellent way to cover your bases, weed out the issues causing problems, prevent them from happening in the future, and guarantee success during future events. If you want to learn more about root cause analysis, you can opt for the Green Belt Certification Training Course, which will give you an in-depth understanding of these tools. 

About the Author


Simplilearn is one of the world’s leading providers of online training for Digital Marketing, Cloud Computing, Project Management, Data Science, IT, Software Development, and many other emerging technologies.

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