Root Cause Analysis (RCA): Definition, Process and Tools

root cause analysis rca toolshero

Root Cause Analysis (RCA): this article explains the Root Cause Analysis or RCA in a practical way. The article starts with a general definition of this concept, followed by the five approaches to the RCA and a practical Root Cause Analysis example. This article also contains a Root Cause Analysis template. Enjoy reading!

What is a Root Cause Analysis (RCA)?

Root Cause Analysis (RCA) is a method of problem solving that aims at identifying the root causes of problems or incidents.

RCA is based on the principle that problems can best be solved by correcting their root causes as opposed to other methods that focus on addressing the symptoms of problems or treating the symptoms.

Free Toolshero ebook

Through corrective actions, the underlying causes are addressed so that recurrence of the problem can be minimized. It is utopian to think that a single corrective action will completely prevent recurrence of the problem. This is why root cause analysis is often considered to be an iterative process.

This problem solving method is often used when something goes wrong, but is also used when it goes well. More on this proactive attitude to problem solving later.

Root cause analyses, as well as incident investigations and other forms of problem solving, are fundamentally linked to the following three questions:

  • What is currently the problem?
  • Why does this problem occur?
  • What can be done to prevent this problem from happening again?

What is the goal of the Root Cause Analysis?

Root Cause Analysis is used as a tool for continuous improvement. If a RCA is used for the first time, it is a reactive way of identifying and solving problems. This means that an analysis is performed after a problem or incident has occurred.

By executing this analysis before problems from occur, its use changes from reactive to proactive, so that problems can be anticipated in time. RCA is not a strictly defined methodology. There are many different tools, processes and philosophies that have been developed based on Root Cause Analysis.

However, there are five approaches that can be identified in practice:


Its origin can be mainly be found in accident analyses, safety and healthcare.


Its origin can be mainly be found in the area of quality control and industrial manufacturing.


This is the follow-up from production and business processes.

Failure-based root

Its origin can be found in Engineering and maintenance.


Its origin can be found in the amalgamation of the approaches mentioned above and this is combined with ideas from change management, risk management and systems analysis.

Despite the fact that there seem to be no clear definition of the differences in the objectives among the various approaches, there are some common principles that can be considered to be universal. It is also possible to define a general process for performing an Root Cause Analysis.

Where is the Root Cause Analysis applied in practice?

The Root Cause Analysis is applied in many areas. Below are some examples where an RCA can make a difference.


When an industrial machine breaks down, an RCA can determine the cause of the defect.

If it turns out that a fuse has blown, the fuse can be replaced and the machine restarted, but then the machine will stop working again after a while.

By performing an RCA it is discovered that the problem lies with a pump in the automatic lubrication mechanism. By determining the root cause of the defect by means of an RCA, the same problem can be prevented after an appropriate response.

Information technology

RCA is also used in IT to track down the root causes of problems. An example of this is the computer security management process. It uses RCA to investigate security breaches.


The RCA is also used in the field of safety and health. Think of diagnoses made in medicine, identifying the source of an epidemic, accident analysis and occupational health.

Root Cause Analysis: the basic process

The basic process consists of a number of basic steps. These corrective measures will lead to the true cause of the problem.

Define the problem or the factual description of the incident

Use both qualitative and quantitative information (nature, size, locations and timing) of the results in question and find the root.

Collect data and evidence and classify

Collect data and evidence and classify them along a time line of incidents until the eventual problem or incident is found. Each special deviation in the form of behaviour, condition, action and passivity must be recorded in the time line.

Ask the why’s

Always ask ‘why’ to identify the effects and record the causes associated with each step in the sequence toward the defined problem or incident.

Classify the causes

Classify the causes within the causal factors that relate to a crucial moment in the sequence including the underlying causes. If there are multiple causes, which is often the case, document these, dig deeper, preferably in order of sequence for a future selection. Identify all other harmful factors and contributing factors.

Generate corrective actions / improvements

Think of corrective actions or improvement measures that will ensure prevention of recurrence with a sufficient degree of certainty.

Explore whether corrective actions or improvement measures can be simulated in advance so that the possible effects become noticeable, also with respect to the other underlying causes.

Think of effective solutions that can prevent recurrence of the causes and to which all involved colleagues and team members can agree. These solutions must comply with the intended goals and objectives and must not cause any new and unforeseen problems.

Implement solutions and monitor these

Implement the solutions (corrective actions) that have been made by consensus. Monitor the effectiveness of the solutions (corrective actions) closely and adjust if necessary.

Other methods for problem-solving and problem prevention may be useful. Identify and address any other causes that may be harmful factors in the process.

Please note: steps three, four and five are the most critical part of the corrective measures because these have proved to be successful in practice.

Root cause analysis tools

Other well-know Root cause analysis techniques and tools are listed below:

Barrier analysis

This root cause analysis technique is often used in the industrial sector.

It was developed to identify energy flows and focus on possible blocks for those flows in order to determine how and why the obstacles cannot prevent the energy flows from causing damage.

Current Reality Tree

This complex but powerful method developed by Eliahu M. Goldratt is based on representing causal factors in a tree structure. This method uses rules of logic. The method starts with a short list of the undesirable factors we see around us that will subsequently lead to one or more underlying causes.

Change analysis

This research methodology is often used for problems or accidents and demonstrates how the problem has presented itself from different perspectives.

5 times why

In the Japanese analysis method 5 whys the question ‘why’ is asked five times. The 5 whys technique was originally developed by Sakichi Toyoda, and was used to trace the root cause of the problems within the manufacturing process of Toyota Motors.

Fishbone diagram

This method is also known as the Ishikawa diagram. The Ishikawa diagram is a much preferred method of project managers to perform a Root Cause Analysis.

Kepner Tregoe method

The Kepner Tregoe Method is a method based on facts in which the possible causes are systematically excluded in order to find the real cause. This method also disconnects the problem is from the decision.

RPR Problem Diagnosis

This is an ITIL aligned method designed to determine the root cause of IT problems.

Core Principles of Root Cause Analysis

While there are many different approaches to Root Cause Analyses, most of the methods boil down to the following five steps.

Identification and description

Problem statements and event descriptions are very helpful and often required to perform a proper Root Cause Analysis. An outage is an example of a problem where this is particularly important.


The Root Cause Analysis must establish a sequence of events or a timeline before the relationship between causal factors can be understood.


It is important to distinguish between root cause, causal factors and non-causal factors. This is done by correlating the sequence of events with the size, nature, and timing of the problem. One way to detect underlying causal factors is to use clustering and data mining.


Finally, from the sequences of events, researchers must create an additional set of events that actually caused the problem. This is then converted into a causal graph. To be effective, the Root Cause Analysis must be performed systematically.

This form of problem solving is often a team effort. Think of the analysis of aircraft accidents. For this, the conclusions of researchers and identified causes must be supported by documented evidence.

Correcting measures

Taking corrective action is not formally part of the RCA as the goal is to eliminate the root cause of a problem. Still, it is an important step that is added to virtually all Root Cause Analyses. This step is therefore to add long-term corrective actions so the problem does not develop in the same way as before.

Root Cause Analysis training

There are various forms of training for managers and other persons for which it is important to carry out a correct RCA. These courses are ideal for people who need to understand Root Cause Analysis terminology and process for professional use. Participating in such training courses helps to understand the importance of identifying the root cause of a problem to ensure it does not recur. In addition, courses help to identify common barriers and problems in conducting a RCA.

Root Cause Analysis summary

A Root Cause Analysis (RCA) is a method for identifying the root causes of various problems. There are several methods and techniques that are used for this purpose: Fishbone Diagram, 5 whys method, Barrier Analysis and the Kepner Tregoe Method.

Although they all differ slightly from each other, the operation of the method can be summarized in three questions: what is the problem, why is this a problem, and what is being done to prevent this problem? In practice, a RCA is used in production facilities, in information technology and the health and safety industry.

Five elements are important in performing the RCA and always come back. First, it is imperative that there is a description and explanation of the events leading up to the identification of the problem. In addition, it is important to establish the correct chronology of these events. Subsequently, it must be possible to clearly distinguish between the root cause, causal factors and non-causal factors.

After this, researchers need to determine the sequence of events that almost certainly led to the problem. The final step usually consists of taking corrective action. While not a formal part of the Root Cause Analysis (RCA), this step is very important to ensure that the problem does not develop in the same way in the future as it did before.

Root Cause Analysis template

Start with the cause and effect analysis and identify the causes of problems with this ready to use Root Cause Analysis template.

Download the Root Cause Analysis template

This template is exclusively for our paying Toolshero members. Click here to see if a membership is something for you!

Join the Toolshero community

It’s Your Turn

What do you think? What is your Root Cause Analysis experience? Do you recognize the practical explanation or do you have additions? What are in your opinion success factors for conducting an RCA?

Share your experience and knowledge in the comments box below.

More information

  1. Andersen, B. & Fagerhaug, T. (2006). Root cause analysis: simplified tools and techniques. ASQ Quality Press.
  2. Barsalou, M. A. (2014). Root Cause Analysis: A Step-By-Step Guide to Using the Right Tool at the Right Time. Productivity Press.
  3. Dankovic, D. D. (2001). Root Cause Analysis. Technometrics, 43(3), 370-371.
  4. George, M. L., Maxey, J., Rowlands, D. & Price, M. (2004). The Lean Six Sigma Pocket Toolbook: A Quick Reference Guide to 100 Tools for Improving Quality and Speed. McGraw-Hill Education.

How to cite this article:
Van Vliet, V. (2010). Root Cause Analysis (RCA). Retrieved [insert date] from Toolshero:

Original publication date: 08/15/2010 | Last update: 06/12/2024

Add a link to this page on your website:
<a href=””>Toolshero: Root Cause Analysis (RCA)</a>

Did you find this article interesting?

Your rating is more than welcome or share this article via Social media!

Average rating 4 / 5. Vote count: 3

No votes so far! Be the first to rate this post.

We are sorry that this post was not useful for you!

Let us improve this post!

Tell us how we can improve this post?

Vincent van Vliet
Article by:

Vincent van Vliet

Vincent van Vliet is co-founder and responsible for the content and release management. Together with the team Vincent sets the strategy and manages the content planning, go-to-market, customer experience and corporate development aspects of the company.


Leave a Reply